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THE HANDBOOK OF THE BRITISH ASTRONOMICAL ASSOCIATION 2019 2018 October ISSN 0068–130–X

The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

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Page 1: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

THE HANDBOOKOF THE

BRITISH ASTRONOMICALASSOCIATION

2019

2018 October ISSN 0068–130–X

Page 2: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

CONTENTSPREFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2HIGHLIGHTS FOR 2019 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3SKY DIARY . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5CALENDAR 2019 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6SUN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9ECLIPSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-17APPEARANCE OF PLANETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18VISIBILITY OF PLANETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19RISING AND SETTING OF THE PLANETS IN LATITUDES 52°N AND 35°S . . . . . . . . . . . . 20-21PLANETS – Explanation of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22ELEMENTS OF PLANETARY ORBITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23MERCURY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24-25VENUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26EARTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27MOON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

LUNAR LIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28MOONRISE AND MOONSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30-33SUN’S SELENOGRAPHIC COLONGITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34LUNAR OCCULTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35-41GRAZING LUNAR OCCULTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42-43

MARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44-45ASTEROIDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

ASTEROID EPHEMERIDES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47-51ASTEROID OCCULTATIONS (incl. TNO Hightlight:28978 Ixion) . . . . . . . . . . . . . . . . . . . . 52-55ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES . . . . . . . . . . . . . . . . . . . . . . . 56-58NEO CLOSE APPROACHES TO EARTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

JUPITER . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60-64SATELLITES OF JUPITER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 64-68JUPITER ECLIPSES, OCCULTATIONS AND TRANSITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69-78

SATURN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79-82SATELLITES OF SATURN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83-86

URANUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87NEPTUNE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88TRANS–NEPTUNIAN & SCATTERED-DISK OBJECTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89DWARF PLANETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90-93COMETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94-98METEOR DIARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99-101VARIABLE STARS (RZ Cassiopeiae; Algol; RS Canum Venaticorum) . . . . . . . . . . . . . . . . . . 102-103MIRA STARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104VARIABLE STAR OF THE YEAR (RS Canum Venaticorum) . . . . . . . . . . . .. . . . . . . . . . . . . . 105-107EPHEMERIDES OF VISUAL BINARY STARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108-109BRIGHT STARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110ACTIVE GALAXIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112-113ASTRONOMICAL AND PHYSICAL CONSTANTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114-115GREEK ALPHABET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115ACKNOWLEDGMENTS / ERRATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

Front Cover: Mercury - taken between 2018 June 25 and July 12 by Simon Kidd using a C14 scope, ASI224MC camera and 742nm filter. Different processing is combined for limb and main image content, owing to extremely low contrast.

Page 3: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

British Astronomical Association

HANDBOOK FOR 2019NINETY–EIGHTH YEAR OF PUBLICATION

BURLINGTON HOUSE, PICCADILLY, LONDON, W1J 0DUTelephone 020 7734 4145

Page 4: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

2 Preface BAA Handbook 2019

PREFACE

Welcome to the 98th Handbook of the British Astronomical Association.

The Handbook highlights forthcoming astronomical events for the year, but there are always events that can be missed, or are entirely unpredictable, like comets, asteroid close approaches, aurorae, etc. Make sure you watch the BAA’s website for the latest news. Also, make sure you are receiving the new email newsletters by keeping your email up to date with the BAA office.

Once again we would also encourage everyone to join their local astronomical society to try equipment, talk to like-minded people, and to give and receive help. It can take a long time to choose the right equipment and learn how to use it, so make the most of your local society. The BAA’s Sections can help too. Contact the Section Directors, who will be pleased to help.

You may also like to consider getting involved with the annual events organised as part of World Space Week (4-10 Oct.). This is an international celebration of all things SPACE and focuses on science and technology and its role in the past, present and future of mankind. World Space Week currently consists of space education and outreach events held by space agencies, aerospace companies, schools, planetaria, museums, and astronomy clubs around the world. (http://www.worldspaceweek.org/).

Unfortunately we are restricted by the number of pages that we can include in the Handbook. This does mean that some things will have to be left out. This edition we have had to remove the Internet Resources pages to make room for more eclipse/transit pages. However, the Computing Section does publish all additional data on the section website (http://britastro.org/computing). This includes both Comet charts and Asteroid Oppositions and Appulses. Members may also like to know that the Computing Section provides the data for the Royal Astronomical Society’s Diary.

Finally, we must thank all the contributors to the Handbook. You will find them acknowledged on page 116. Contact details for many of these can be found at the back of every Journal. Alternatively, email the Director, Steve Harvey (address below) and messages can be forwarded to those concerned.

Clear skies for 2019 !

Steve HarveyDirector, Computing SectionEmail: [email protected]

August 2018

Page 5: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

BAA Handbook 2019 Highlights 3

HIGHLIGHTS FOR 2019The following events during 2019 are worthy of note:Sun and Moon:There will be five eclipses (three of the Sun and two of the Moon). The first being a partial solar eclipse followed by a total (visible form South America) and an Annular at the end of the year (vis-ible from Southern India and Indonesia). The first lunar eclipse is full and visible (early morning) from the UK Jan.21. There will also be a partial lunar eclipse July 16.There will be a transit of Mercury visible from the UK. Nov. 11. The next one will not be until 2032.

Planets, Dwarf Planets and Asteroids:Mercury is best seen around the time of greatest elongation. For the mornings, this will be April 11, August 9 and November 28. Whilst for evening apparitions it will be February 27, June 23 and October 20.Venus is a morning object for the first half of the year before moving into visibility at dusk for the latter part of the year. It is at Greatest Western Elongation of 47 degrees from the Sun on January 6. Mars is visible as an all night object until the middle of the year.

Meteors:Among the meteor showers, the most favourable are: the Quadrantids (January), Bootids (June) and AlphaCapricornids (July) . Southern Delta Aquarids (July) and the Ursids (December). Also favourable are: Alpha Aurigids, Camelopardalids and Alpha Monocerotids

Comets:There are no particularly bright comets predicted for 2019. However it is generally worth paying attention to (due to its tendency to outburst) is Comet 29P/Schwassmann-Wachmann.Refer to the BAA Comet Section for latest info : http://britastro.org/comet

Space Probes and Artificial Satellites:Pluto visitor New Horizons will fly past 2014 MU69 on Jan 1. United Launch Alliance (ULA) aim to launch the Solar Orbiter Probe in February, using the new Atlas V rocket. SpaceX plan to land an autonomous vehicle on the Moon, ULA also plan to launch a two-man crew to the International Space Station (ISS) using the CST-100 Starliner.Positional predictions for the ISS and other bright satellites can be found for any geographic loca-tion at: location at: http://www.heavens-above.com

Highlights by date: Jan. 6 Partial solar eclipse visible from north east Asia Jan. 21 Total lunar eclipse visible from central Pacific, Americas, Europe and Africa Mar. 20 The vernal equinox occurs in the northern hemisphere at 21:58 UT Apr. 22 Lyrid meteor shower Jun. 10 Jupiter at opposition Jul. 10 Saturn at opposition Jun. 21 The summer solstice occurs in the northern hemisphere at 15:54 UT Jul. 2 Total solar eclipse visible over Chile and Argentina 14 Pluto at opposition 16 Partial lunar eclipse visible South America, Europe, Africa, Asia and Australia Aug. 13 Perseid meteor shower Sep. 10 Neptune at opposition 23 The autumnal equinox occurs in the northern hemisphere at 07:50 UT Oct. 28 Uranus at opposition Nov. 11 Transit of Mercury 18 Leonids meteor shower Dec. 14 Geminids meteor shower 22 The winter solstice occurs in the northern hemisphere at 04:19 UT 26 Annular eclipse of the sun visible from Saudi Arabia, India and Indonesia

In addition, the Moon occults the planets Venus (twice), Jupiter, and Saturn (12 times) as indicated by the Sky Diary (next page).

Page 6: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

4 Sky Diary BAA Handbook 2019

SKY DIARY m d h Phenomenon m d h Lunation

1 01 22 Venus 1.3°S of Moon 1 02 05 Saturn in Conjunction with Sun 1 04 03 Quadrantid Meteor Shower 1 06 01 New Moon 1 06 02 Partial Solar Eclipse 1 06 05 Venus at Greatest Elong: 47.0°W 1 14 07 First Quarter Moon

1 17 18 Aldebaran 1.6°S of Moon 1 21 05 Total Lunar Eclipse 1 21 05 Full Moon 1 21 16 Beehive Cluster 0.6°N of Moon 1 27 21 Last Quarter Moon 1 30 03 Mercury at Superior Conjunction 1 31 18 Venus 0.1°S of Moon: Occn. 2 02 07 Saturn 0.6°S of Moon: Occn. 2 04 21 New Moon 2 12 22 First Quarter Moon

2 18 03 Beehive Cluster 0.6°N of Moon 2 19 16 Full Moon 2 26 11 Last Quarter Moon 2 27 01 Mercury at Greatest Elong: 18.1°E 3 01 17 Saturn 0.3°S of Moon: Occn. 3 02 21 Venus 1.2°N of Moon 3 06 16 New Moon

3 07 01 Neptune in Conjunction with Sun 3 13 10 Aldebaran 1.9°S of Moon 3 14 10 First Quarter Moon 3 15 02 Mercury at Inferior Conjunction 3 17 13 Beehive Cluster 0.5°N of Moon 3 20 22 Vernal Equinox 3 21 02 Full Moon 3 27 02 Jupiter 1.9°S of Moon 3 28 04 Last Quarter Moon 3 29 05 Saturn 0.1°N of Moon: Occn. 4 02 04 Venus 2.7°N of Moon 4 05 09 New Moon 4 11 19 Mercury at Greatest Elong: 27.7°W 4 12 19 First Quarter Moon 4 13 20 Beehive Cluster 0.2°N of Moon 4 19 11 Full Moon 4 22 16 Lyrid Meteor Shower 4 23 00 Uranus in Conjunction with Sun 4 25 15 Saturn 0.4°N of Moon: Occn. 4 26 22 Last Quarter Moon 5 04 23 New Moon 5 05 13 Eta-Aquarid Meteor Shower 5 11 02 Beehive Cluster 0.0°S of Moon 5 12 01 First Quarter Moon 5 18 21 Full Moon 5 21 13 Mercury at Superior Conjunction 5 22 23 Saturn 0.5°N of Moon: Occn. 5 26 16 Last Quarter Moon 6 03 10 New Moon 6 07 07 Beehive Cluster 0.2°S of Moon 6 10 06 First Quarter Moon 6 10 15 Jupiter at Opposition 6 17 08 Full Moon 6 18 18 Mercury 0.2° of Mars 6 19 04 Saturn 0.4°N of Moon: Occn. 6 21 16 Summer Solstice 6 23 23 Mercury at Greatest Elong: 25.2°E 6 25 10 Last Quarter Moon

Page 7: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

BAA Handbook 2019 Sky Diary 5

SKY DIARYcont'd m d h Phenomenon m d h Lunation 7 02 19 New Moon 7 12 05 Mercury greatest elongation E(26°) 7 02 19 Total Solar Eclipse 7 04 15 Beehive Cluster 0.2°S of Moon 7 09 11 First Quarter Moon 7 09 16 Saturn at Opposition

7 13 07 Mars 0.4°S of Beehive Cluster 7 16 07 Saturn 0.2°N of Moon: Occn. 7 16 21 Partial Lunar Eclipse 7 16 22 Full Moon 7 21 13 Mercury at Inferior Conjunction 7 25 01 Last Quarter Moon 7 28 15 Delta-Aquarid Meteor Shower 8 01 03 New Moon 8 07 17 First Quarter Moon 8 09 23 Mercury at Greatest Elong: 19.0°W 8 12 10 Saturn 0.0°N of Moon: Occn. 8 13 07 Perseid Meteor Shower 8 14 06 Venus at Superior Conjunction 8 15 12 Full Moon 8 23 15 Last Quarter Moon 8 28 11 Beehive Cluster 0.2°S of Moon 8 30 11 New Moon 9 02 10 Mars in Conjunction with Sun 9 04 01 Mercury at Superior Conjunction 9 06 03 First Quarter Moon 9 08 16 Saturn 0.0°N of Moon: Occn. 9 10 06 Neptune at Opposition 9 14 04 Full Moon 9 22 03 Last Quarter Moon 9 23 08 Autumnal Equinox 9 24 21 Beehive Cluster 0.4°S of Moon 9 28 18 New Moon 10 05 16 First Quarter Moon 10 05 21 Saturn 0.3°N of Moon: Occn. 10 13 21 Full Moon 10 20 04 Mercury at Greatest Elong: 24.6°E 10 21 13 Last Quarter Moon 10 21 23 Orionid Meteor Shower 10 22 05 Beehive Cluster 0.6°S of Moon 10 28 04 New Moon 10 28 08 Uranus at Opposition 11 02 07 Saturn 0.6°N of Moon: Occn. 11 04 10 First Quarter Moon 11 06 00 Taurid Meteor Shower 11 11 15 Mercury at Inferior Conjunction (Transit) 11 12 14 Full Moon 11 18 23 Leonid Meteor Shower 11 18 10 Beehive Cluster 0.9°S of Moon 11 19 21 Last Quarter Moon 11 26 15 New Moon 11 28 10 Mercury at Greatest Elong: 20.1°W 11 28 11 Jupiter 0.7°S of Moon: Occn. 11 29 04 Moon at Descending Node 11 29 21 Saturn 0.9°N of Moon: Occn. 12 04 07 First Quarter Moon 12 12 05 Full Moon 12 14 18 Geminid Meteor Shower 12 19 05 Last Quarter Moon 12 22 04 Winter Solstice 12 23 03 Ursid Meteor Shower 12 26 05 New Moon 12 26 05 Annular Solar Eclipse 12 27 18 Jupiter in Conjunction with Sun 12 29 01 Venus 1.0°N of Moon: Occn.

Page 8: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

6 BAA Handbook 2019

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BAA Handbook 2019 Sun 7

SUNThe tables on p.8–9 give the apparent RA, Dec. and diameter of the Sun, the UT of transit across the Greenwich meridian, and P, B0, L0 where

P is the position angle of the N end of the axis of rotation. It is positive when east of the north point of the disk, negative if west; B0 is the heliographic latitude of the centre of the disk; L0 is the heliographic longitude of the centre of the disk.

Decrease of L0 with Time h m º h m º h m º h m º h º

0 00 0.0 1 43 1.0 3 32 2.0 5 21 3.0 6 3.3 05 0.1 54 1.1 43 2.1 32 3.1 8 4.4 16 0.2 2 05 1.2 54 2.2 43 3.2 10 5.5 27 0.3 16 1.3 4 05 2.3 54 3.3 12 6.6 38 0.4 27 1.4 16 2.4 6 05 3.4 14 7.7 49 0.5 38 1.5 27 2.5 16 3.5 16 8.8 1 00 0.6 49 1.6 38 2.6 27 3.6 18 9.9 10 0.7 3 00 1.7 49 2.7 38 3.7 20 11.0 21 0.8 10 l.8 5 00 2.8 49 3.8 22 12.1 32 0.9 21 1.9 10 2.9 7 00 3.9 24 13.2 43 1.0 32 2.0 21 3.0 10 4.0

The heliographic longitude and latitude of a spot may be conveniently estimated by the method described in J. Br. Astron. Assoc., 53, 63 (1943).

Carrington Rotation NumberThe dates of commencement of the synodic rotations, in continuation of Carrington’s (Greenwich Photo–Heliographic) series, are as follows: Rotation Begins Rotation Begins Rotation Begins d d d 2213 Jan. 16.83 2214 Feb. 13.17 2215 Mar. 12.50 2216 Apr. 8.80 2217 May 6.05 2218 Jun. 2.27 2219 Jun. 29.47 2220 Jul. 26.67 2221 Aug. 22.90 2222 Sep. 19.16 2223 Oct. 16.44 2224 Nov. 12.74 2225 Dec. 10.04

At the date of commencement of each synodic rotation period the value of L0 is zero; that is, the prime meridian passes through the central point of the disk.The sidereal period of rotation of the Sun used in physical ephemerides is 25.38 mean solar days, after Carrington; the mean synodic rotation period is 27.2753d

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8 Sun BAA Handbook 2019

SUN

2018/9 RA Dec. Diam. Transit P B0 L0 h m ° ' ' " h m ° ° °Dec 29 18 31.4 –23 14 32 32 12 02 3.66 –2.61 247.92

Jan 3 18 53.0 –22 52 32 32 12 04 1.24 –3.20 182.07 8 19 15.0 –22 18 32 32 12 07 –1.18 –3.77 116.22 13 19 37.0 –21 33 32 32 12 09 –3.57 –4.30 50.38 18 19 58.0 –20 38 32 31 12 10 –5.91 –4.80 344.54 23 20 19.0 –19 33 32 30 12 12 –8.18 –5.27 278.70 28 20 40.0 –18 19 32 29 12 13 –10.36 –5.69 212.87

Feb 2 21 1.0 –16 57 32 28 12 14 –12.44 –6.06 147.04 7 21 21.0 –15 27 32 26 12 14 –14.40 –6.39 81.21 12 21 41.0 –13 51 32 25 12 14 –16.24 –6.67 15.38 17 22 0.0 –12 09 32 23 12 14 –17.94 –6.89 309.54 22 22 20.0 –10 22 32 21 12 14 –19.50 –7.07 243.69 27 22 38.0 –8 32 32 18 12 13 –20.90 –7.18 177.84

Mar 4 22 57.0 –6 38 32 16 12 12 –22.16 –7.24 111.98 9 23 16.0 –4 41 32 13 12 11 –23.26 –7.25 46.10 14 23 34.0 –2 44 32 11 12 09 –24.19 –7.19 340.22 19 23 53.0 –0 45 32 08 12 08 –24.95 –7.09 274.31 24 0 11.0 +1 12 32 06 12 06 –25.54 –6.93 208.39 29 0 29.0 +3 10 32 03 12 05 –25.96 –6.72 142.45

Apr 3 0 47.0 +5 06 32 00 12 03 –26.20 –6.46 76.49 8 1 5.0 +7 00 31 57 12 02 –26.26 –6.15 10.52 13 1 24.0 +8 51 31 55 12 01 –26.14 –5.80 304.52 18 1 42.0 +10 38 31 52 11 59 –25.84 –5.41 238.50 23 2 1.0 +12 21 31 49 11 58 –25.35 –4.98 172.46 28 2 20.0 +13 59 31 47 11 58 –24.68 –4.51 106.40May 3 2 39.0 +15 31 31 44 11 57 –23.82 –4.02 40.33 8 2 58.0 +16 56 31 42 11 57 –22.79 –3.49 334.23 13 3 18.0 +18 15 31 40 11 56 –21.58 –2.95 268.12 18 3 37.0 +19 26 31 38 11 56 –20.21 –2.38 201.99 23 3 57.0 +20 28 31 36 11 57 –18.67 –1.80 135.85 28 4 18.0 +21 22 31 34 11 57 –16.99 –1.21 69.70

Jun 2 4 38.0 +22 06 31 33 11 58 –15.18 –0.60 3.53 7 4 59.0 +22 41 31 31 11 59 –13.24 0.00 297.36 12 5 19.0 +23 06 31 30 12 00 –11.20 0.60 231.19 17 5 40.0 +23 21 31 29 12 01 –9.08 1.20 165.00 22 6 1.0 +23 25 31 29 12 02 –6.89 1.79 98.82 27 6 22.0 +23 20 31 28 12 03 –4.65 2.37 32.63

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BAA Handbook 2019 Sun 9

SUN

2019/20 RA Dec. Diam. Transit P B0 L0 h m ° ' ' " h m ° ° °Jul 2 6 42.0 +23 04 31 28 12 04 –2.39 2.93 326.45 7 7 3.0 +22 37 31 28 12 05 –0.13 3.47 260.27 12 7 23.0 +22 01 31 28 12 06 2.13 3.98 194.10 17 7 44.0 +21 16 31 28 12 06 4.35 4.47 127.93 22 8 4.0 +20 22 31 29 12 06 6.52 4.93 61.77 27 8 24.0 +19 19 31 30 12 07 8.63 5.36 355.63

Aug 1 8 43.0 +18 08 31 31 12 06 10.67 5.75 289.49 6 9 2.0 +16 49 31 32 12 06 12.61 6.10 223.37 11 9 22.0 +15 24 31 33 12 05 14.46 6.40 157.26 16 9 40.0 +13 53 31 35 12 04 16.20 6.67 91.16 21 9 59.0 +12 16 31 37 12 03 17.82 6.88 25.07 26 10 17.0 +10 35 31 39 12 02 19.33 7.05 319.00 31 10 36.0 +8 49 31 41 12 00 20.70 7.17 252.94

Sep 5 10 54.0 +6 59 31 43 11 59 21.93 7.24 186.90 10 11 12.0 +5 07 31 46 11 57 23.03 7.25 120.87 15 11 30.0 +3 13 31 48 11 55 23.97 7.22 54.85 20 11 48.0 +1 17 31 51 11 54 24.76 7.13 348.84 25 12 6.0 –0 39 31 53 11 52 25.39 6.98 282.84 30 12 24.0 –2 35 31 56 11 50 25.86 6.79 216.85

Oct 5 12 42.0 –4 32 31 59 11 48 26.15 6.55 150.88 10 13 0.0 –6 26 32 02 11 47 26.26 6.25 84.91 15 13 18.0 –8 19 32 04 11 46 26.20 5.91 18.95 20 13 37.0 –10 09 32 07 11 45 25.94 5.53 312.99 25 13 56.0 –11 55 32 10 11 44 25.49 5.10 247.05 30 14 15.0 –13 36 32 12 11 44 24.85 4.63 181.11

Nov 4 14 35.0 –15 12 32 15 11 44 24.02 4.13 115.18 9 14 55.0 –16 42 32 17 11 44 22.98 3.59 49.26 14 15 15.0 –18 05 32 20 11 44 21.76 3.03 343.34 19 15 36.0 –19 20 32 22 11 45 20.34 2.44 277.42 24 15 57.0 –20 26 32 24 11 47 18.75 1.83 211.51 29 16 18.0 –21 23 32 26 11 48 16.98 1.20 145.62

Dec 4 16 39.0 –22 09 32 27 11 50 15.05 0.57 79.72 9 17 1.0 –22 45 32 29 11 52 12.99 –0.07 13.83 14 17 23.0 –23 10 32 30 11 54 10.81 –0.71 307.95 19 17 45.0 –23 23 32 31 11 57 8.53 –1.35 242.08 24 18 8.0 –23 25 32 31 11 59 6.18 –1.97 176.21 29 18 30.0 –23 15 32 32 12 02 3.78 –2.58 110.35

Jan 3 18 52.0 –22 53 32 32 12 04 1.35 –3.17 44.50

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10 Eclipses BAA Handbook 2019

ECLIPSES

During 2019 there will be three eclipses of the Sun and two of the Moon.There will also be a transit of Mercury.

1. A partial eclipse of the Sun on January 6 will be visible over north-eastern Asia, Northern Pacific and parts of Alaska.

2. A total lunar eclipse on January 21 will be visible from central America, Portugal, Eire and the UK. Northern parts of Spain and France will also be able to watch the whole eclipse.

3. A total solar eclipse on July 2 is visible from the South Pacific and South America - Chile and Argentina.

4. A partial lunar eclipse on July 16 is visible in South America, Europe, Africa, Asia, Australisia

5. An annular solar eclipse on December 26 is visible in Saudi Arabia, Oman, India, Sinagpore and Indonesia.

6. A transit of Mercury on November 11 is visble in entirety from the Americas. Maximum transit shall occur a little before sunset, as viewed from the UK.

Solar Eclipse Mailing ListThe solar eclipse community is very active and there is a plethora of websites devoted entirely to the subject. To keep up to date join the Solar Eclipse mailing list:

http://groups.yahoo.com/group/SEML/Useful eclipse websites include:For weather predictions : Jay Anderson's site: http://eclipsophile.com/For general information : Xavier Jubier's site: http://xjubier.free.fr/en/index_en.html or Fred Espenak's: http://www.mreclipse.com/ & http://astropixels.com/

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BAA Handbook 2019 Eclipses 11

ECLIPSES

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12 Eclipses BAA Handbook 2019

ECLIPSES

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BAA Handbook 2019 Eclipses 13

ECLIPSES

Page 16: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

14 Eclipses BAA Handbook 2019

ECLIPSES

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BAA Handbook 2019 Eclipses 15

ECLIPSES

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16 Eclipses BAA Handbook 2019

ECLIPSES

Transit of Mercury - November 11In the present epoch, transits of Mercury occur in May or November. May transits are roughlyhalf as frequent as November transits and this is the last November transit until 2032. The dates of transits are drifting later in the year. In the early 1500s they were in April and October.The interval between May transits is 13 or 33 years, and November transit intervals are 7, 13,or 33 years. For May transits, Mercury has a diameter of 12" and occur at the descending node of Mercury’s orbit. For November transits, Mercury has a diameter of 10" and occur at the ascending node. May transits are less frequent than November transits because during a May transit, Mercury is near aphelion whereas during a November transit, it is near perihelion.Perihelion transits occur more frequently because Mercury moves faster in its orbit at perihelion and can reach the transit node more quickly, and at perihelion Mercury has less parallax asit is closer to the Sun.Previous Mercury transits were in November 2006 and May 2016, the next are November 2032 and Novem-ber 2039. For reference, the next Venus transit is not until 2117 December 11.The transit is visible in its entirety from Central and South America and Eastern USA. The UK, Europe and Africa will not see the Egress stage and the rest of the USA shall not see the Ingress stage as the transit is already in progress at sunrise. No part is visible from Australasia, Japan, and Indonesia.

Times differ little throughout the world and even less from within the UK:

Location I II G III IV Duration

London 12:35:35 12:37:16 15:19:44 16:34* 3h 58m 25s

Glasgow 12:35:38 12:37:19 14:56:22 16:14* 3h 38m 22s

Belfast 12:35:38 12:37:19 15:19:47 16:25* 3h 49m 22s

Cardiff 12:35:36 12:37:17 15:19:44 16:26* 3h 50m 24s

New York 12:36:04 12:37:45 15:20:13 18:02:39 18:04:20 5h 28m 16s

Rio de Janeiro 12:35:44 12:37:25 15:19:40 18:02:02 18:03:43 5h 27m 59s* Transit ends at sunset / All times are UT (GMT) /See diagram for positions of I, II, G, III and IV

UK Circumstances:

Solar Semidiameter : 16' 09.3"Semidiameter of Mercury : 0' 05.0"(note path after sunset is greyed out).

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BAA Handbook 2019 Eclipses 17

ECLIPSES

Ecliptic

I II

Maximum

III IV

N

E

S

W

0 5 10 15Arc-Minutes

N

S

E W

P.A.

G GI III IIIII III

IV IV

Entire TransitVisible

Transit in Progressat Sunset

No TransitVisible

Transit in Progressat Sunrise

Mercury Transit of 2019 Nov 11Geocentric Diagram and Visibility Map

Greatest Transit: 15:19:47.4 UT J.D.: 2458799.138743

Constants

ΔT: 69.70s

Transit Geocentric Contacts

I: 12:35:26 UTC (109.8°)

II: 12:37:08 UTC (109.8°)

G: 15:19:47 UTC (24.3°)

III: 18:02:33 UTC (298.8°)

IV: 18:04:14 UTC (298.7°)

Geocentric Data

Minimum separation: 75.9”

General Duration: 05h28m47s

Central Duration: 05h25m25s

(http://xjubier.free.fr/)

Mercury Venus Transit Maestro - Xavier M. Jubier

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18 Appearance of Planets BAA Handbook 2019

APP

EA

RA

NC

E O

F PL

AN

ET

S

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BAA Handbook 2019 Visibility of Planets 19

VISIBILITY OF PLANETSThe diagrams on pp 20–21, drawn for latitudes N 52° and S 35° respectively, show the times for the risings and settings of the Sun and the planets. The beginning and end of astronomical twilight (Sun 18° below horizon) is also shown. The times are in Local Mean Time and are thus in GMT (which is equal to UT) for Greenwich.

Since dates change at midnight, the dates at the top differ by one day from those at the foot. Each vertical line, followed upwards, indicates the succession of phenomena in the course of one night.Thus, at latitude N 52° on the night of June 9/10, Venus rises at 3h 00m and Mercury sets at21h 55m, Mars sets at 22h 15m and Saturn rises at the same time. Jupiter rises at 0h 35m. Uranus rises about 1h 50m. all events occurring during twilight. Sunrise is at 03h 40m and sunset at 20h 20m, (Timings in UT derived from the diagram to nearest 5 minutes).

The UT of any phenomenon seen from elsewhere than Greenwich may be obtained as follows:

1. For longitudes east of Greenwich, subtract the longitude, expressed as time. For longitudes west of Greenwich, add the longitude expressed as time. (One degree of longitude represents 4 minutes.) This applies both to rising and to setting times.

2. Correct for latitude using a value for Δh from the table below. Add Δh, for setting times and subtract Δh for rising times. The correction should be obtained by interpolating in both latitude and declination.

Δh TABLE Latitude Dec. Latitude N 58° N 55° N 50° N 40° N 30° N 20° 0° S 20° S 25° S 30° S 40° S 45° m m m m m m ° m m m m m m

+69 +29 –15 –70 –106 –134 29 +91 +45 +31 +17 –20 –43 +62 +26 –14 –66 –100 –127 28 +87 +43 +30 +16 –19 –41 +56 +24 –13 –62 –94 –120 27 +84 +41 +29 +15 –18 –39 +51 +22 –12 –58 –89 –114 26 +80 +39 +27 +14 –17 –37 +46 +20 –12 –54 –84 –107 25 +76 +37 +26 +14 –16 –35 +31 +14 –8 –40 –63 –81 20 +59 +29 +20 +11 –12 –26 +21 +10 –6 –28 –45 –58 15 +43 +21 +15 +8 –9 –19 +13 +6 –4 –18 –29 –37 10 +28 +14 +10 +5 –6 –12 +6 +3 –2 –9 –14 –18 5 +14 +7 +5 +2 –3 –6 0 0 0 0 0 0 0 0 0 0 0 0 0

If Dec. is negative, reverse the sign of Δh.

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20 Visibility of Planets BAA Handbook 2019

RIS

ING

AN

D S

ET

TIN

G O

F PL

AN

ET

S

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BAA Handbook 2019 Visibility of Planets 21

RIS

ING

AN

D S

ET

TIN

G O

F PL

AN

ET

S

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22 Planets BAA Handbook 2019

PLANETSThe ephemerides of all the planets (except the dwarf planets and the minor planets), and also the diagrams for Uranus and Neptune, are referred to the apparent equinox, so that the RA and Dec. required for setting on the telescope are obtained directly from the ephemeris. For the minor planets and comets, astrometric ephemerides referred to the equinox of 2000.0 are given. Thus they are directly comparable with star catalogues and atlases referred to this epoch; however, precession should be applied to their positions before setting on a telescope. The magnitudes given are visual. For the minor planets, it should be noted that photographic magnitudes are fainter by about 0.7.The Sky Diary lists other phenomena in chronological order. Relative positions in the Diary are geocentric. Some headings in the tables are abbreviated, as follows:

a = Length of semi–major axis of orbit auCM = The longitude of central meridian °DE = Planetocentric declination of the Earth (called ‘Tilt’ in previous Handbooks) °DS = Planetocentric declination of the Sun °e = Eccentricity of orbit Elong. = Elongation of the planet from the Sun (where + is east and – is west) °H = Mean absolute asteroid magnitude i = Inclination °LS = The planetocentric longitude of the Sun, measured in the plane of the orbit from its ascending node on the Martian equator and given as a direct and exact indicator of the Martian season. The Martian Vernal Equinox (N. Hemisphere) occurs when LS = 0°. °M = Mean anomaly at the epoch °V = Visual magnitude Node = Longitude of the ascending node °P = Position angle of the axis of rotation, or of an occultation, measured eastwards from the north point of the disk °Peri. = Argument of perihelion °Ph. = Phase, the fraction of the disk area that is illuminated Q = Position angle of the point of greatest defect of illumination. The position angle of the line of cusps is Q±90°. °r = Heliocentric distance auU = Uncertainty codeΔ = Distance from Earth au

λ☉ = Solar longitude °Longitudes of central meridians refer to the geometric disks.

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BAA Handbook 2019 Elements of Planetary Orbits 23

ELEMENTS OF PLANETARY ORBITS

KEPLERIAN ELEMENTS FOR THE EPOCH 2019 JAN. 0.5 TT

Mean Longitude Mean Longitude Mean Longitude Inclination at the of the of the to the Mean Planet Epoch Perihelion Ascending Node Ecliptic Eccentricity Distance L ϖ Ω i e a

º º º º auMercury 210.055 77.488 48.307 7.004 0.20564 0.387Venus 139.580 131.603 76.627 3.394 0.00677 0.723Earth 99.863 102.999 .. .. 0.01670 1.000Mars 31.848 336.141 49.504 1.848 0.09341 1.524Jupiter 250.958 14.769 100.513 1.304 0.04836 5.203Saturn 282.212 92.519 113.608 2.486 0.05376 9.536Uranus 34.644 171.032 74.025 0.772 0.04725 19.189Neptune 346.384 44.904 131.783 1.770 0.00860 30.070

Keplerian elements are referred to the mean ecliptic and adjusted for best fit. The elements can be used for the determination of approximate positions of the planets according to Standish, E.M. and Williams, J.G.:

http://ssd.jpl.nasa.gov/txt/aprx_pos_planets.pdf

Sidereal Mean Mean Perihelion Aphelion Mean Daily Sidereal Synodic Orbital Distance Distance Motion Period Period Velocity q Q n P au au ° d d km/sMercury 0.30750 0.46670 4.09234 87.9681 115.88 47.87Venus 0.71844 0.72822 1.60214 224.697 583.91 35.02Earth 0.9833 1.0167 0.98561 365.253 n/a 29.78Mars 1.3813 1.6660 0.52404 686.963 779.94 24.13Jupiter 4.9501 5.4551 0.08306 4334.35 398.87 13.06Saturn 9.0247 10.085 0.03337 10787.8 378.05 9.64Uranus 18.327 20.110 0.01170 30773.0 369.64 6.79Neptune 29.826 30.395 0.00597 60348.7 367.48 5.43

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24 Mercury BAA Handbook 2019

MERCURYMorning Apparition

Greatest Elongation W Superior Conjunction Apr. 11 (28°) Jan. 30 Aug. 9 (19°) May 21 Nov. 28 (20°) Sep. 4 When best seen: Northern Hemisphere: early to mid Jan., late Aug. to mid Sept., December Southern Hemisphere: January, early Apr. to late May, mid-late Aug., December

2019 RA Dec V Diam Ph. Elong. CM Δh m ° ' " ° ° au

Jan. –3 17 8.5 –22 16 –0.4 5.4 0.856 –18 355 1.2442 17 39.6 –23 21 –0.4 5.1 0.901 –16 19 1.3087 18 12.2 –24 00 –0.5 4.9 0.933 –14 42 1.357

12 18 45.8 –24 08 –0.6 4.8 0.957 –11 65 1.39217 19 20.1 –23 43 –0.7 4.7 0.975 –8 88 1.41422 19 54.8 –22 43 –0.9 4.7 0.988 –5 110 1.42327 20 29.9 –21 06 –1.2 4.7 0.997 –2 133 1.418

Mar. 18 23 23.6 +0 34 4.2 11.0 0.021 –6 32 0.60923 23 11.4 –3 03 2.4 10.7 0.098 –14 67 0.62628 23 7.8 –4 49 1.4 10.0 0.204 –21 99 0.670

Apr. 2 23 12.8 –5 33 0.9 9.1 0.309 –25 129 0.7317 23 24.8 –5 19 0.6 8.4 0.402 –27 157 0.800

12 23 41.9 –4 13 0.4 7.7 0.484 –28 183 0.87217 0 2.9 –2 26 0.2 7.1 0.557 –27 209 0.94622 0 27.0 +0 02 0.0 6.5 0.627 –25 233 1.02027 0 53.9 +2 51 –0.1 6.1 0.695 –23 256 1.093

May 2 1 23.5 +6 10 –0.4 5.7 0.766 –20 279 1.1637 1 56.1 +9 48 –0.7 5.4 0.841 –16 301 1.227

12 2 32.2 +13 37 –1.1 5.2 0.916 –11 322 1.28117 3 12.2 +17 24 –1.7 5.1 0.977 –5 342 1.315

Jul. 26 7 47.0 +16 19 3.8 10.9 0.033 –7 347 0.61331 7 40.8 +17 24 2.3 9.8 0.111 –14 19 0.678

Aug. 5 7 44.6 +18 29 1.0 8.6 0.237 –18 49 0.77410 7 59.7 +19 10 0.1 7.5 0.403 –19 76 0.89315 8 25.4 +19 06 –0.6 6.5 0.594 –18 101 1.02420 8 59.3 +17 59 –1.0 5.8 0.778 –15 124 1.15025 9 37.4 +15 46 –1.4 5.3 0.912 –10 145 1.25430 10 16.1 +12 38 –1.6 5.0 0.980 –5 166 1.327

Sep. 4 10 53.0 +8 58 –1.8 4.9 0.998 0 187 1.369Nov. 13 14 59.3 –16 29 4.6 9.8 0.008 –3 190 0.682

18 14 41.9 –13 46 1.4 8.9 0.157 –13 226 0.75123 14 41.4 –13 07 0.0 7.7 0.393 –18 257 0.86828 14 55.1 –14 11 –0.5 6.7 0.598 –20 284 0.994

Dec. 3 15 17.4 –16 07 –0.6 6.0 0.741 –19 309 1.1108 15 44.4 –18 18 –0.6 5.5 0.835 –18 333 1.208

13 16 14.0 –20 21 –0.6 5.2 0.895 –15 357 1.28618 16 45.4 –22 06 –0.6 5.0 0.934 –13 20 1.34623 17 18.1 –23 27 –0.6 4.8 0.961 –10 43 1.39128 17 51.8 –24 19 –0.7 4.7 0.979 –8 66 1.42033 18 26.3 –24 39 –0.9 4.7 0.991 –5 89 1.436

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BAA Handbook 2019 Mercury 25

MERCURYEvening Apparition

Greatest Elongation E Inferior Conjunction Feb. 27 (18°) Mar. 15 Jun. 23 (25°) Jul. 21 Oct. 20 (25°) Nov. 11 (Transit)

When best seen: Northern Hemisphere: Mar., mid Jun. to early Jul. Southern Hemisphere: mid June to late July, early Oct. to late Nov.

2019 RA Dec V Diam. Ph. Elong. CM Δh m ° ' " ° ° au

Feb. 1 21 5.0 –18 51 –1.4 4.8 0.997 1 155 1.3976 21 40.0 –16 00 –1.3 4.9 0.985 5 177 1.359

11 22 14.4 –12 33 –1.2 5.1 0.950 9 198 1.29816 22 47.3 –8 38 –1.1 5.5 0.872 13 220 1.21021 23 17.0 –4 33 –1.0 6.1 0.733 16 242 1.095

26 23 40.1 +0 48 –0.5 7.0 0.530 18 266 0.959Mar. 3 23 52.7 +1 51 0.4 8.1 0.303 17 293 0.822

8 23 52.0 +2 47 2.0 9.4 0.115 12 323 0.70713 23 39.9 +1 46 4.3 10.5 0.016 4 357 0.634

May 22 3 55.9 +20 48 –2.3 5.1 1.000 1 2 1.321

27 4 41.8 +23 27 –1.7 5.2 0.961 7 22 1.292Jun. 1 5 27.2 +25 01 –1.1 5.4 0.870 12 42 1.231

6 6 9.5 +25 30 –0.7 5.8 0.757 17 63 1.14911 6 47.1 +25 03 –0.3 6.3 0.644 21 85 1.05816 7 19.3 +23 54 0.0 6.9 0.541 23 109 0.965

21 7 45.5 +22 19 0.4 7.6 0.446 25 133 0.87526 8 5.5 +20 30 0.7 8.4 0.357 25 159 0.792

Jul. 1 8 18.7 +18 41 1.1 9.3 0.269 24 186 0.7176 8 24.5 +17 05 1.7 10.2 0.182 21 215 0.654

11 8 22.4 +15 55 2.5 11.0 0.101 16 246 0.607

16 8 13.2 +15 23 3.7 11.5 0.038 9 279 0.58021 7 59.7 +15 33 4.8 11.5 0.010 1 313 0.580

Sep. 9 11 27.5 +5 04 –1.3 4.8 0.989 4 208 1.38614 11 59.7 +1 07 –0.9 4.8 0.966 9 230 1.38319 12 30.0 –2 44 –0.6 4.9 0.938 12 252 1.366

24 12 58.8 –6 26 –0.4 5.0 0.906 15 274 1.33729 13 26.5 –9 53 –0.3 5.2 0.870 18 297 1.296

Oct. 4 13 53.3 –13 04 –0.2 5.4 0.830 20 321 1.2459 14 19.1 –15 56 –0.1 5.6 0.782 22 345 1.184

14 14 43.6 –18 24 –0.1 6.0 0.722 24 9 1.112

19 15 6.0 –20 24 –0.1 6.5 0.644 24 34 1.03024 15 24.7 –21 49 0.0 7.1 0.538 24 60 0.93929 15 36.7 –22 25 0.3 7.9 0.397 22 88 0.841

Nov. 3 15 37.5 –21 53 1.0 8.9 0.219 17 119 0.7508 15 23.3 –19 48 3.0 9.7 0.050 8 153 0.686

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26 Venus BAA Handbook 2019

VENUSSuperior Conjunction : Aug. 14

Greatest elongation W : Jan. 6 (47°) Inferior Conjunction : -

2019 RA Dec. V Diam. Ph. Elong. Δh m ° ' " ° au

Jan. –3 15 12.5 –14 23 –4.5 27.6 0.451 –47 0.6047 15 52.3 –16 41 –4.4 24.5 0.506 –47 0.680

17 16 35.6 –18 45 –4.4 22.1 0.556 –47 0.75627 17 21.8 –20 18 –4.3 20.1 0.600 –46 0.832

Feb. 6 18 10.1 –21 07 –4.2 18.4 0.641 –45 0.906

16 18 59.7 –21 02 –4.2 17.5 0.678 –43 0.97826 19 49.6 –20 00 –4.1 15.9 0.712 –41 1.049

Mar. 8 20 39.1 –18 01 –4.1 14.9 0.744 –40 1.11818 21 27.6 –15 12 –4.0 14.0 0.773 –38 1.18528 22 14.8 –11 39 –4.0 13.4 0.801 –36 1.249

Apr. 7 23 0.8 –7 33 –4.0 12.7 0.826 –33 1.31017 23 46.0 –3 06 –3.9 12.2 0.850 –31 1.36927 0 30.7 +1 33 –3.9 11.7 0.873 –29 1.424

May 7 1 15.6 +6 12 –3.9 11.3 0.893 –26 1.47617 2 1.3 +10 39 –3.9 10.9 0.913 –24 1.524

27 2 48.3 +14 43 –3.9 10.6 0.930 –21 1.568Jun. 6 3 36.9 +18 13 –3.9 10.4 0.946 –19 1.607

16 4 27.4 +20 56 –3.9 10.2 0.960 –16 1.64126 5 19.5 +22 43 –3.9 10.0 0.972 –13 1.670

Jul. 6 6 12.6 +23 25 –3.9 9.9 0.982 –11 1.694

16 7 6.0 +22 59 –3.9 9.7 0.990 –8 1.71226 7 58.7 +21 26 –3.9 9.7 0.996 –5 1.724

Aug. 5 8 50.0 +18 50 –3.9 9.6 0.999 –3 1.73014 9 39.6 +15 21 –3.9 9.6 1.000 1 1.73125 10 27.5 +11 10 –3.9 9.7 0.998 3 1.726

Sep. 4 11 13.9 +6 29 –3.9 9.7 0.995 6 1.71614 11 59.5 +1 29 –3.9 9.8 0.989 8 1.70024 12 44.8 –3 36 –3.9 9.9 0.982 11 1.680

Oct. 4 13 30.6 –8 36 –3.9 10.0 0.972 14 1.656

14 14 17.6 –13 16 –3.9 10.3 0.961 16 1.62724 15 6.2 –17 25 –3.9 10.5 0.949 19 1.594

Nov. 3 15 56.9 –20 49 –3.9 10.7 0.935 21 1.55813 16 49.5 –23 16 –3.9 11.0 0.920 24 1.51823 17 43.5 –24 35 –3.9 11.3 0.903 26 1.475

Dec. 3 18 38.1 –24 40 –3.9 11.7 0.884 28 1.42913 19 32.1 –23 31 –4.0 12.1 0.864 30 1.37923 20 24.5 –21 13 –4.0 12.6 0.843 33 1.32733 21 14.7 –17 54 –4.0 13.1 0.819 35 1.272

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BAA Handbook 2019 Earth / Moon 27

EARTH Perihelion Jan. 03d 05h 20m (147,099,766 km, 0.9833012 au) Aphelion Jul. 04d 22h 11m (152,104,278 km, 1.0167543 au) Equinoxes Mar. 20d 22h 00m Sep. 23d 07h 51m Solstices Jun. 21d 15h 55m Dec. 22d 04h 21m

Obliquity 2000 23.43929° 2019 23.43681°

MOON

PHASES OF THE MOON

New Moon First Quarter Full Moon Last Quarter d h m d h m d h m d h mJan 6 01 29 Jan 14 06 47 Jan 21 05 17 Jan 27 21 11Feb 4 21 05 Feb 12 22 27 Feb 19 15 55 Feb 26 11 29Mar 6 16 05 Mar 14 10 28 Mar 21 01 44 Mar 28 04 11Apr 5 08 52 Apr 12 19 07 Apr 19 11 13 Apr 26 22 19May 4 22 47 May 12 01 13 May 18 21 13 May 26 16 35Jun 3 10 03 Jun 10 06 0 Jun 17 08 32 Jun 25 09 48Jul 2 19 17 Jul 9 10 56 Jul 16 21 39 Jul 25 01 19Aug 1 03 13 Aug 7 17 32 Aug 15 12 30 Aug 23 14 57Aug 30 10 38 Sep 6 03 12 Sep 14 04 34 Sep 22 02 42Sep 28 18 28 Oct 5 16 48 Oct 13 21 09 Oct 21 12 40Oct 28 03 40 Nov 4 10 24 Nov 12 13 36 Nov 19 21 12Nov 26 15 07 Dec 4 06 59 Dec 12 05 13 Dec 19 04 58Dec 26 05 14

APSIDES

PERIGEE APOGEE Date Diam. Date Diam. Date Diam. Date Diam. d h ' " d h ' " d h ' " d h ' "Jan 21 20 33 26 Jul 5 05 32 51 Jan 9 04 29 25 Jul 21 00 29 58Feb 19 09 33 30 Aug 2 07 33 15 Feb 5 09 29 54 Aug 17 11 29 55Mar 19 20 33 15 Aug 30 16 33 27 Mar 4 11 29 54 Sep 13 13 29 54Apr 16 22 32 49 Sep 28 02 33 24 Apr 1 00 29 58 Oct 10 18 29 56May 13 22 32 23 Oct 26 10 33 04 Apr 28 18 30 02 Nov 7 08 30 00Jun 7 23 32 26 Nov 23 07 32 35 May 26 13 30 04 Dec 5 04 30 03 Dec 18 20 32 16 Jun 23 08 30 02

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28 Lunar BAA Handbook 2019

LUNAR LIBRATION

The libration data are given in two forms: as a size and position angle (P); and as the selenographic longitude and latitude of the centre of the disk.The position angle identifies the point on the edge of the disk most displaced towards the centre of the disk from its mean position and is measured from the North point of the disk (NOT the North Pole of the Moon, which usually does not coincide with the North point of the disk) anticlockwise through celestial East, as shown in Fig. 1. In Fig. 1 N, E, S and W are directions in the sky.Selenographic longitude and latitude are analogous to geographic longitude and latitude, with latitudes of +90º and –90º identifying the Moon's North and South Poles, around which the Moon rotates. Positive longitudes are in the Moon's Eastern hemisphere and negative longitudes in the Moon's Western hemisphere, as shown in Fig. 2 for the case of zero libration. For zero libration the selenographic longitude and latitude of the centre of the disk are both 0º.Note that the Eastern hemisphere (positive selenographic longitude) of the Moon in Fig. 2 roughly corresponds to the Western side (in terms of sky direction) of the disk in Fig. 1.

Maximum Minimum Date Size P Sel Lon Sel Lat Date Size P Sel Lon Sel Lat d º º º º d º º º º Jan. 15.23 10.1 29 –7.5 6.8 Jan. 7.58 1.2 298 0.9 0.8 27.72 10.1 247 7.5 –6.7 21.52 1.4 153 –0.9 –1.0 Feb. 12.06 9.9 32 –7.5 6.5 Feb. 4.13 1.8 299 1.3 1.3 24.63 9.9 247 7.6 –6.4 18.62 2.8 158 –1.8 –2.1 Mar. 11.39 9.1 29 –6.5 6.3 Mar. 3.71 2.4 300 1.7 1.8 24.48 9.0 244 6.8 –5.9 18.44 3.9 158 –2.6 –2.9 Apr. 7.08 8.2 20 –5.2 6.4 31.17 3.0 300 2.0 2.2 20.87 7.9 238 5.5 –5.8 Apr. 14.27 4.1 143 –3.4 –2.4 May 3.94 8.0 16 –4.6 6.5 27.38 3.3 299 2.3 2.4 17.55 7.4 231 4.1 –6.2 May 10.7 3.2 130 –2.9 –1.4 31.25 8.3 17 –5.0 6.6 24.38 3.3 296 2.5 2.2 Jun. 13.36 7.8 233 4.3 –6.5 Jun. 6.78 2.5 135 –2.1 –1.3 27.91 8.7 22 –5.7 6.6 20.46 3.2 293 2.6 2.0 Jul. 10.64 8.6 239 5.5 –6.5 Jul. 4.30 2.6 145 –2.0 –1.7 25.78 9.0 28 –6.4 6.3 17.86 3.5 293 2.7 2.2 Aug. 7.36 9.2 245 6.8 –6.2 Aug. 1.20 3.5 154 –2.4 –2.5 22.70 8.7 34 –6.6 5.7 14.55 4.0 296 2.9 2.8 Sep. 4.38 9.3 249 7.5 –5.5 29.33 4.6 162 –2.8 –3.6 19.13 7.9 33 –5.9 5.4 Sep. 11.37 4.8 299 3.2 3.6 Oct. 2.52 8.6 250 7.4 –4.4 26.44 5.6 168 –3.1 –4.7 15.01 7.1 12 –3.6 6.1 Oct. 9.12 5.5 301 3.4 4.3 30.46 7.4 249 6.5 –3.6 21.70 6.0 124 –5.7 –2.1 Nov. 10.51 6.9 0 –2.5 6.5 Nov. 5.42 5.9 301 3.7 4.6 23.15 6.7 208 0.7 –6.6 16.82 4.8 105 –4.8 –0.6 Dec. 7.91 7.1 2 –2.8 6.6 30.98 5.8 283 5.1 2.7 20.64 6.9 216 1.7 –6.7 Dec. 14.52 4.2 120 –3.9 –1.4 27.02 5.0 271 4.9 0.8

Fig. 1 Fig. 2

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BAA Handbook 2019 Lunar 29

1. For a moonrise, R1, use the previous moonset, S0, and the following moonset, S2. Form

a = –2R1+S0+S2+8m

2. For a moonset, S1, use the previous moonrise, R0, and the following moonrise, R2. Form

a = 2S1–R0–R2+8m

3. Enter the table on the right with argument a and obtain the Moon’s Dec., by mental interpolation, to 0.1º.

4. Enter the table on p.19 with this Dec. and the required latitude to obtain Δh.5. Moonrise for required latitude = R1 – 1.04 Δh. Moonset for required latitude = S1 + 1.04 Δh. The accuracy of the times so derived is ±3m.

The times thus found are for longitude 0º. For other longitudes it is necessary to calculate the times of the previous (fol-lowing) similar phenomenon at the standard latitude if the observer is east (west) of Greenwich and then interpolate them to the observer’s longitude.

These calculations are most conveniently carried out using a spreadsheet or suit-able applet. Observers are referred to the BAA's Computing Section webpage for support in doing these calculations:

http://britastro.org/computing/applets_moonrts.html

On the four following pages are given the times (UT) of moonrise and moonset for longitude 0°, in the standard latitudes of N 52° and S 35°. Observers in most other latitudes can determine approximate times using the following method, where the times of moonrise and moonset are for the standard latitude in the same hemisphere as the observer. The basis of the method is given in J. Br. Astron. Assoc., 86, 416 (1976).

N 52° S 35° a Dec. a h m ° h m

0 00 0 0 00 0 21 1 0 12 0 42 2 0 23 1 03 3 0 35 1 25 4 0 46 1 46 5 0 58 2 07 6 1 10 2 29 7 1 21 2 51 8 1 33 3 13 9 1 45 3 35 10 1 57 3 58 11 2 09 4 20 12 2 21 4 44 13 2 33 5 07 14 2 46 5 31 15 2 58 5 56 16 3 11 6 21 17 3 24 6 46 18 3 37 7 12 19 3 51 7 39 20 4 04 8 07 21 4 18 8 35 22 4 32 9 05 23 4 46 9 36 24 5 01 10 08 25 5 16 10 41 26 5 31 11 16 27 5 47 11 53 28 6 03 12 31 29 6 20samesignas a

oppsignto a

Dec} {

MOONRISE AND MOONSET

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30 Lunar BAA Handbook 2019

MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE N 52º LATITUDE N 52º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Day h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 03:10 13:22 05:24 13:42 04:13 12:26 04:40 14:17 03:49 15:22 03:11 17:46 02:38 19:05 04:24 20:24 07:35 20:10 09:18 19:20 11:51 19:46 12:01 20:32 2 04:21 13:49 06:16 14:31 04:59 13:20 05:03 15:22 04:07 16:30 03:36 19:00 03:24 20:11 05:48 20:57 09:00 20:33 10:38 19:50 12:44 20:42 12:30 21:39 3 05:29 14:21 07:00 15:27 05:37 14:20 05:24 16:29 04:26 17:40 04:06 20:14 04:22 21:07 07:13 21:23 10:22 20:56 11:54 20:25 13:27 21:44 12:54 22:47 4 06:32 14:59 07:36 16:28 06:09 15:23 05:43 17:36 04:46 18:51 04:46 21:24 05:32 21:52 08:38 21:47 11:42 21:22 13:02 21:07 14:01 22:49 13:14 23:54 5 07:29 15:44 08:05 17:31 06:35 16:27 06:02 18:44 05:08 20:05 05:36 22:24 06:51 22:28 10:01 22:09 12:57 21:53 14:01 21:58 14:27 23:56 13:32 ––:––

6 08:19 16:37 08:31 18:36 06:58 17:33 06:21 19:54 05:35 21:18 06:38 23:14 08:13 22:57 11:22 22:31 14:08 22:30 14:48 22:55 14:49 ––:–– 13:48 01:00 7 09:00 17:35 08:52 19:42 07:18 18:39 06:42 21:05 06:09 22:29 07:50 23:54 09:36 23:21 12:40 22:54 15:11 23:14 15:27 23:57 15:08 01:02 14:04 02:07 8 09:34 18:37 09:12 20:48 07:37 19:46 07:05 22:17 06:51 23:33 09:08 ––:–– 10:57 23:43 13:56 23:21 16:04 ––:–– 15:57 ––:–– 15:25 02:09 14:22 03:15 9 10:02 19:41 09:31 21:54 07:56 20:54 07:34 23:28 07:45 ––:–– 10:29 00:26 12:16 ––:–– 15:08 23:53 16:48 00:06 16:22 01:02 15:42 03:15 14:42 04:24 10 10:26 20:46 09:50 23:02 08:15 22:03 08:10 ––:–– 08:49 00:29 11:50 00:52 13:34 00:04 16:15 ––:–– 17:23 01:04 16:43 02:09 15:59 04:23 15:05 05:36

11 10:47 21:51 10:10 ––:–– 08:37 23:13 08:55 00:36 10:02 01:14 13:09 01:15 14:51 00:26 17:15 00:32 17:52 02:07 17:01 03:15 16:17 05:32 15:35 06:49 12 11:06 22:57 10:33 00:12 09:02 ––:–– 09:52 01:37 11:21 01:51 14:27 01:36 16:05 00:50 18:05 01:18 18:16 03:13 17:18 04:21 16:38 ––:–– 16:14 ––:–– 13 11:25 ––:–– 11:01 01:23 09:33 00:24 10:59 02:29 12:41 02:20 15:45 01:57 17:16 01:18 18:47 02:12 18:36 04:19 17:35 05:28 17:04 07:53 17:04 09:07 14 11:45 00:05 11:35 02:36 10:12 01:35 12:15 03:12 14:02 02:45 17:02 02:20 18:22 01:52 19:20 03:12 18:54 ––:–– 17:52 ––:–– 17:37 09:05 18:06 10:04 15 12:07 01:15 12:19 03:47 11:01 02:41 13:36 03:47 15:22 03:08 18:17 02:45 19:19 02:33 19:47 ––:–– 19:11 06:31 18:12 07:44 18:19 10:13 19:19 10:51

16 12:32 02:27 13:16 04:54 12:03 03:41 14:59 04:15 16:42 03:30 19:27 03:16 20:07 ––:–– 20:10 05:22 19:28 07:37 18:35 08:54 19:13 11:15 20:37 11:28 17 13:03 03:42 14:25 05:52 13:16 04:31 16:22 04:41 18:02 03:52 20:31 ––:–– 20:47 04:19 20:30 06:28 19:47 08:44 19:02 10:04 20:17 12:08 21:58 11:58 18 13:44 04:57 15:45 06:40 14:37 05:13 17:44 05:04 19:20 ––:–– 21:26 04:38 21:18 05:21 20:48 07:34 20:07 09:52 19:38 11:14 21:30 12:50 23:20 12:22 19 14:35 06:09 17:10 ––:–– 16:01 05:46 19:06 ––:–– 20:34 04:44 22:11 05:30 21:44 06:26 21:05 08:39 20:31 11:02 20:23 12:19 22:49 13:24 06:10 ––:–– 20 15:40 07:14 18:36 07:50 17:27 ––:–– 20:26 05:50 21:43 05:18 22:47 06:30 22:05 07:32 21:22 09:46 21:01 12:12 21:19 13:18 06:29 ––:–– 00:40 13:03

21 16:57 ––:–– 20:01 08:17 18:51 06:40 21:42 06:17 22:43 05:59 23:16 07:33 22:24 08:38 21:41 10:53 21:40 13:20 22:27 14:07 00:11 14:15 02:01 13:24 22 18:20 08:51 21:23 08:41 20:14 07:03 22:54 06:48 23:33 06:47 23:40 08:38 22:42 09:44 22:03 12:02 22:30 14:25 23:44 14:47 01:33 14:36 03:21 13:46 23 19:45 09:25 22:42 09:05 21:34 07:27 23:58 07:25 03:37 ––:–– 04:38 ––:–– 22:59 10:50 22:30 13:12 23:32 15:22 07:40 ––:–– 02:55 14:57 04:41 14:12 24 21:08 09:54 23:58 09:28 22:51 07:52 04:04 ––:–– 00:14 08:44 00:00 10:51 23:17 11:57 23:04 14:23 07:55 ––:–– 01:06 15:47 04:18 15:19 06:00 14:43 25 22:28 10:18 05:01 ––:–– 03:40 ––:–– 00:53 09:00 00:46 09:48 00:19 11:57 23:38 13:05 23:48 15:32 00:46 16:48 02:30 16:10 05:41 15:43 07:14 15:23 26 23:45 10:41 01:10 10:24 00:04 08:54 01:38 09:57 01:13 10:53 00:36 13:04 06:50 ––:–– 08:10 ––:–– 02:08 17:19 03:56 16:32 07:03 16:12 08:19 16:11 27 05:30 ––:–– 02:18 10:58 01:10 09:33 02:14 10:59 01:35 11:59 00:54 14:13 00:02 15:29 00:45 17:31 03:34 17:46 05:21 16:54 08:21 16:48 09:14 17:09 28 01:00 11:27 03:19 11:39 02:08 10:19 02:44 12:03 01:55 13:06 01:14 15:24 00:33 16:42 01:55 18:16 05:01 18:09 06:46 17:18 09:33 17:32 09:57 18:14 29 02:12 11:53 02:58 11:12 03:09 13:09 02:13 14:13 01:36 16:37 01:12 17:51 03:15 18:52 06:28 18:32 08:10 17:45 10:34 18:25 10:31 19:22 30 03:21 12:23 03:39 12:10 03:30 14:15 02:31 15:22 02:04 17:52 02:03 18:53 04:41 19:22 07:54 18:55 09:31 18:18 11:23 19:26 10:57 20:30

31 04:26 12:59 04:12 13:12 02:50 16:33 03:07 19:44 06:09 19:47 10:45 18:57 11:19 21:38

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BAA Handbook 2019 Lunar 31

MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE N 52º LATITUDE N 52º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Day h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 03:10 13:22 05:24 13:42 04:13 12:26 04:40 14:17 03:49 15:22 03:11 17:46 02:38 19:05 04:24 20:24 07:35 20:10 09:18 19:20 11:51 19:46 12:01 20:32 2 04:21 13:49 06:16 14:31 04:59 13:20 05:03 15:22 04:07 16:30 03:36 19:00 03:24 20:11 05:48 20:57 09:00 20:33 10:38 19:50 12:44 20:42 12:30 21:39 3 05:29 14:21 07:00 15:27 05:37 14:20 05:24 16:29 04:26 17:40 04:06 20:14 04:22 21:07 07:13 21:23 10:22 20:56 11:54 20:25 13:27 21:44 12:54 22:47 4 06:32 14:59 07:36 16:28 06:09 15:23 05:43 17:36 04:46 18:51 04:46 21:24 05:32 21:52 08:38 21:47 11:42 21:22 13:02 21:07 14:01 22:49 13:14 23:54 5 07:29 15:44 08:05 17:31 06:35 16:27 06:02 18:44 05:08 20:05 05:36 22:24 06:51 22:28 10:01 22:09 12:57 21:53 14:01 21:58 14:27 23:56 13:32 ––:––

6 08:19 16:37 08:31 18:36 06:58 17:33 06:21 19:54 05:35 21:18 06:38 23:14 08:13 22:57 11:22 22:31 14:08 22:30 14:48 22:55 14:49 ––:–– 13:48 01:00 7 09:00 17:35 08:52 19:42 07:18 18:39 06:42 21:05 06:09 22:29 07:50 23:54 09:36 23:21 12:40 22:54 15:11 23:14 15:27 23:57 15:08 01:02 14:04 02:07 8 09:34 18:37 09:12 20:48 07:37 19:46 07:05 22:17 06:51 23:33 09:08 ––:–– 10:57 23:43 13:56 23:21 16:04 ––:–– 15:57 ––:–– 15:25 02:09 14:22 03:15 9 10:02 19:41 09:31 21:54 07:56 20:54 07:34 23:28 07:45 ––:–– 10:29 00:26 12:16 ––:–– 15:08 23:53 16:48 00:06 16:22 01:02 15:42 03:15 14:42 04:24 10 10:26 20:46 09:50 23:02 08:15 22:03 08:10 ––:–– 08:49 00:29 11:50 00:52 13:34 00:04 16:15 ––:–– 17:23 01:04 16:43 02:09 15:59 04:23 15:05 05:36

11 10:47 21:51 10:10 ––:–– 08:37 23:13 08:55 00:36 10:02 01:14 13:09 01:15 14:51 00:26 17:15 00:32 17:52 02:07 17:01 03:15 16:17 05:32 15:35 06:49 12 11:06 22:57 10:33 00:12 09:02 ––:–– 09:52 01:37 11:21 01:51 14:27 01:36 16:05 00:50 18:05 01:18 18:16 03:13 17:18 04:21 16:38 ––:–– 16:14 ––:–– 13 11:25 ––:–– 11:01 01:23 09:33 00:24 10:59 02:29 12:41 02:20 15:45 01:57 17:16 01:18 18:47 02:12 18:36 04:19 17:35 05:28 17:04 07:53 17:04 09:07 14 11:45 00:05 11:35 02:36 10:12 01:35 12:15 03:12 14:02 02:45 17:02 02:20 18:22 01:52 19:20 03:12 18:54 ––:–– 17:52 ––:–– 17:37 09:05 18:06 10:04 15 12:07 01:15 12:19 03:47 11:01 02:41 13:36 03:47 15:22 03:08 18:17 02:45 19:19 02:33 19:47 ––:–– 19:11 06:31 18:12 07:44 18:19 10:13 19:19 10:51

16 12:32 02:27 13:16 04:54 12:03 03:41 14:59 04:15 16:42 03:30 19:27 03:16 20:07 ––:–– 20:10 05:22 19:28 07:37 18:35 08:54 19:13 11:15 20:37 11:28 17 13:03 03:42 14:25 05:52 13:16 04:31 16:22 04:41 18:02 03:52 20:31 ––:–– 20:47 04:19 20:30 06:28 19:47 08:44 19:02 10:04 20:17 12:08 21:58 11:58 18 13:44 04:57 15:45 06:40 14:37 05:13 17:44 05:04 19:20 ––:–– 21:26 04:38 21:18 05:21 20:48 07:34 20:07 09:52 19:38 11:14 21:30 12:50 23:20 12:22 19 14:35 06:09 17:10 ––:–– 16:01 05:46 19:06 ––:–– 20:34 04:44 22:11 05:30 21:44 06:26 21:05 08:39 20:31 11:02 20:23 12:19 22:49 13:24 06:10 ––:–– 20 15:40 07:14 18:36 07:50 17:27 ––:–– 20:26 05:50 21:43 05:18 22:47 06:30 22:05 07:32 21:22 09:46 21:01 12:12 21:19 13:18 06:29 ––:–– 00:40 13:03

21 16:57 ––:–– 20:01 08:17 18:51 06:40 21:42 06:17 22:43 05:59 23:16 07:33 22:24 08:38 21:41 10:53 21:40 13:20 22:27 14:07 00:11 14:15 02:01 13:24 22 18:20 08:51 21:23 08:41 20:14 07:03 22:54 06:48 23:33 06:47 23:40 08:38 22:42 09:44 22:03 12:02 22:30 14:25 23:44 14:47 01:33 14:36 03:21 13:46 23 19:45 09:25 22:42 09:05 21:34 07:27 23:58 07:25 03:37 ––:–– 04:38 ––:–– 22:59 10:50 22:30 13:12 23:32 15:22 07:40 ––:–– 02:55 14:57 04:41 14:12 24 21:08 09:54 23:58 09:28 22:51 07:52 04:04 ––:–– 00:14 08:44 00:00 10:51 23:17 11:57 23:04 14:23 07:55 ––:–– 01:06 15:47 04:18 15:19 06:00 14:43 25 22:28 10:18 05:01 ––:–– 03:40 ––:–– 00:53 09:00 00:46 09:48 00:19 11:57 23:38 13:05 23:48 15:32 00:46 16:48 02:30 16:10 05:41 15:43 07:14 15:23 26 23:45 10:41 01:10 10:24 00:04 08:54 01:38 09:57 01:13 10:53 00:36 13:04 06:50 ––:–– 08:10 ––:–– 02:08 17:19 03:56 16:32 07:03 16:12 08:19 16:11 27 05:30 ––:–– 02:18 10:58 01:10 09:33 02:14 10:59 01:35 11:59 00:54 14:13 00:02 15:29 00:45 17:31 03:34 17:46 05:21 16:54 08:21 16:48 09:14 17:09 28 01:00 11:27 03:19 11:39 02:08 10:19 02:44 12:03 01:55 13:06 01:14 15:24 00:33 16:42 01:55 18:16 05:01 18:09 06:46 17:18 09:33 17:32 09:57 18:14 29 02:12 11:53 02:58 11:12 03:09 13:09 02:13 14:13 01:36 16:37 01:12 17:51 03:15 18:52 06:28 18:32 08:10 17:45 10:34 18:25 10:31 19:22 30 03:21 12:23 03:39 12:10 03:30 14:15 02:31 15:22 02:04 17:52 02:03 18:53 04:41 19:22 07:54 18:55 09:31 18:18 11:23 19:26 10:57 20:30

31 04:26 12:59 04:12 13:12 02:50 16:33 03:07 19:44 06:09 19:47 10:45 18:57 11:19 21:38

Page 34: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

32 Lunar BAA Handbook 2019

MOONRISE AND MOONSET MOONRISE AND MOONSET LATITUDE S 35º LATITUDE S 35º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise SetDay h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 01:37 15:11 02:17 16:52 01:01 15:38 02:26 16:17 03:03 15:49 04:42 15:53 05:36 15:55 07:17 17:50 07:55 20:15 07:38 21:20 08:25 23:13 08:57 23:24 2 02:13 16:11 03:05 17:40 01:51 16:23 03:21 16:48 03:59 16:19 05:45 16:32 06:40 16:50 08:04 19:03 08:31 21:24 08:17 22:27 09:18 ––:–– 09:55 ––:–– 3 02:51 17:08 03:56 18:25 02:44 17:04 04:17 17:19 04:57 16:49 06:49 17:16 07:42 17:53 08:46 20:15 09:07 22:31 09:00 23:30 10:14 00:04 10:52 00:01 4 03:34 18:04 04:49 19:04 03:38 17:41 05:12 17:48 05:56 17:21 07:53 18:07 08:38 19:01 09:24 21:25 09:44 23:37 09:46 ––:–– 11:10 00:49 11:48 00:33 5 04:20 18:56 05:44 19:40 04:33 18:15 06:09 18:17 06:56 17:56 08:56 19:05 09:28 20:12 10:00 22:33 10:23 ––:–– 10:36 00:29 12:07 01:27 12:43 01:03

6 05:09 19:43 06:39 20:13 05:28 18:46 07:06 18:48 07:59 18:37 09:54 20:08 10:11 21:22 10:34 23:39 11:06 00:40 11:29 01:22 13:02 02:01 13:38 01:30 7 06:01 20:26 07:34 20:44 06:24 19:16 08:05 19:21 09:02 19:23 10:46 21:16 10:50 22:30 11:09 ––:–– 11:52 01:40 12:24 02:09 13:58 02:32 14:33 01:58 8 06:55 21:05 08:29 21:13 07:19 19:46 09:05 19:58 10:04 20:15 11:31 22:24 11:26 23:37 11:46 00:43 12:42 02:35 13:19 02:50 14:53 03:01 15:30 02:26 9 07:50 21:39 09:24 21:43 08:15 20:15 10:07 20:39 11:04 21:14 12:12 23:32 11:59 ––:–– 12:25 01:46 13:35 03:25 14:15 03:27 15:48 03:29 16:29 02:55 10 08:45 22:11 10:20 22:13 09:12 20:46 11:09 21:26 11:58 22:17 12:49 ––:–– 12:33 00:42 13:08 02:47 14:30 04:10 15:11 04:00 16:44 03:56 17:29 03:28

11 09:40 22:42 11:18 22:45 10:11 21:20 12:09 22:20 12:47 23:24 13:23 00:39 13:08 01:47 13:56 03:45 15:26 04:50 16:06 04:30 17:42 04:25 18:32 04:06 12 10:35 23:11 12:17 23:20 11:11 21:58 13:07 23:20 13:31 ––:–– 13:57 01:44 13:45 02:50 14:46 04:38 16:21 05:25 17:01 04:58 18:41 ––:–– 19:34 ––:–– 13 11:31 23:41 13:19 ––:–– 12:12 22:41 14:00 ––:–– 14:10 00:32 14:31 02:49 14:26 03:52 15:40 05:27 17:17 05:57 17:56 05:26 19:42 05:31 20:34 05:39 14 12:28 ––:–– 14:22 00:00 13:14 23:31 14:48 00:25 14:46 01:40 15:07 03:54 15:10 04:52 16:35 06:10 18:12 ––:–– 18:53 ––:–– 20:43 06:10 21:30 06:36 15 13:28 00:12 15:26 00:47 14:15 ––:–– 15:31 01:34 15:21 02:47 15:45 04:58 15:59 05:50 17:31 ––:–– 19:07 06:55 19:50 06:23 21:44 06:55 22:19 07:39 16 14:30 00:46 16:28 01:42 15:12 00:28 16:10 02:43 15:55 03:54 16:28 06:00 16:51 ––:–– 18:27 07:23 20:02 07:23 20:49 06:55 22:41 07:47 23:03 08:46 17 15:35 01:25 17:26 02:44 16:05 01:32 16:47 03:53 16:31 05:00 17:15 ––:–– 17:46 07:30 19:22 07:55 20:58 07:51 21:49 07:31 23:33 08:45 23:43 09:54 18 16:41 02:10 18:18 03:53 16:53 02:40 17:23 05:02 17:09 ––:–– 18:06 07:57 18:42 08:12 20:17 08:24 21:55 08:21 22:49 08:11 04:39 ––:–– 05:19 ––:–– 19 17:47 03:02 19:05 ––:–– 17:36 03:52 17:59 ––:–– 17:50 07:11 19:00 08:48 19:38 08:49 21:11 08:52 22:54 08:54 23:48 08:58 00:20 10:54 00:18 12:09 20 18:48 04:03 19:47 06:19 18:16 ––:–– 18:36 07:18 18:35 08:14 19:55 09:34 20:34 09:22 22:07 09:20 23:54 09:31 04:50 ––:–– 01:02 12:02 00:52 13:15

21 19:44 ––:–– 20:25 07:31 18:53 06:15 19:16 08:24 19:24 09:13 20:51 10:14 21:28 09:53 23:03 09:49 05:06 ––:–– 00:44 10:51 01:40 13:10 01:25 14:22 22 20:33 06:22 21:01 08:40 19:29 07:25 19:59 09:28 20:16 10:07 21:47 10:49 22:23 10:21 04:44 ––:–– 00:55 11:03 01:35 11:56 02:16 14:18 01:59 15:28 23 21:16 07:34 21:36 09:48 20:06 08:33 20:45 10:29 21:11 10:55 22:42 11:22 23:18 10:49 00:02 10:54 01:54 12:00 02:21 13:04 02:50 15:26 02:36 16:35 24 21:55 08:45 22:12 10:53 20:44 09:39 21:35 11:25 22:06 11:38 23:37 11:51 05:21 ––:–– 01:02 11:34 02:49 13:03 03:03 14:14 03:24 16:35 03:16 17:41 25 22:30 09:54 22:50 11:56 21:25 10:43 22:28 12:16 23:02 12:16 06:02 ––:–– 00:15 11:48 02:04 12:20 03:40 14:12 03:41 15:25 04:01 17:44 04:01 18:44

26 23:05 10:59 23:31 12:56 22:08 11:44 23:22 13:01 23:57 12:50 00:32 12:48 01:13 12:21 03:06 13:14 04:27 15:24 04:17 16:35 04:40 18:52 04:51 19:42 27 23:39 12:03 06:40 ––:–– 22:55 12:41 06:34 ––:–– 06:42 ––:–– 01:29 13:18 02:14 12:58 04:06 14:16 05:08 16:37 04:53 17:46 05:23 19:57 05:45 20:33 28 06:18 ––:–– 00:14 14:48 23:45 13:34 00:17 14:17 00:52 13:50 02:27 13:50 03:16 13:42 05:01 15:25 05:47 17:49 05:29 18:56 06:11 20:59 06:43 21:19 29 00:14 14:05 07:04 ––:–– 01:12 14:50 01:48 14:19 03:28 14:25 04:20 14:33 05:52 16:37 06:24 19:01 06:08 20:06 07:04 21:54 07:41 21:58 30 00:52 15:03 00:37 15:04 02:08 15:20 02:44 14:48 04:31 15:07 05:23 15:33 06:37 17:51 07:00 20:11 06:49 21:13 08:00 22:43 08:39 22:32

31 01:33 15:59 01:31 15:42 03:42 15:19 06:23 16:39 07:18 19:03 07:35 22:16 09:36 23:03

Page 35: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

BAA Handbook 2019 Lunar 33

MOONRISE AND MOONSET MOONRISE AND MOONSET LATITUDE S 35º LATITUDE S 35º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise SetDay h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 01:37 15:11 02:17 16:52 01:01 15:38 02:26 16:17 03:03 15:49 04:42 15:53 05:36 15:55 07:17 17:50 07:55 20:15 07:38 21:20 08:25 23:13 08:57 23:24 2 02:13 16:11 03:05 17:40 01:51 16:23 03:21 16:48 03:59 16:19 05:45 16:32 06:40 16:50 08:04 19:03 08:31 21:24 08:17 22:27 09:18 ––:–– 09:55 ––:–– 3 02:51 17:08 03:56 18:25 02:44 17:04 04:17 17:19 04:57 16:49 06:49 17:16 07:42 17:53 08:46 20:15 09:07 22:31 09:00 23:30 10:14 00:04 10:52 00:01 4 03:34 18:04 04:49 19:04 03:38 17:41 05:12 17:48 05:56 17:21 07:53 18:07 08:38 19:01 09:24 21:25 09:44 23:37 09:46 ––:–– 11:10 00:49 11:48 00:33 5 04:20 18:56 05:44 19:40 04:33 18:15 06:09 18:17 06:56 17:56 08:56 19:05 09:28 20:12 10:00 22:33 10:23 ––:–– 10:36 00:29 12:07 01:27 12:43 01:03

6 05:09 19:43 06:39 20:13 05:28 18:46 07:06 18:48 07:59 18:37 09:54 20:08 10:11 21:22 10:34 23:39 11:06 00:40 11:29 01:22 13:02 02:01 13:38 01:30 7 06:01 20:26 07:34 20:44 06:24 19:16 08:05 19:21 09:02 19:23 10:46 21:16 10:50 22:30 11:09 ––:–– 11:52 01:40 12:24 02:09 13:58 02:32 14:33 01:58 8 06:55 21:05 08:29 21:13 07:19 19:46 09:05 19:58 10:04 20:15 11:31 22:24 11:26 23:37 11:46 00:43 12:42 02:35 13:19 02:50 14:53 03:01 15:30 02:26 9 07:50 21:39 09:24 21:43 08:15 20:15 10:07 20:39 11:04 21:14 12:12 23:32 11:59 ––:–– 12:25 01:46 13:35 03:25 14:15 03:27 15:48 03:29 16:29 02:55 10 08:45 22:11 10:20 22:13 09:12 20:46 11:09 21:26 11:58 22:17 12:49 ––:–– 12:33 00:42 13:08 02:47 14:30 04:10 15:11 04:00 16:44 03:56 17:29 03:28

11 09:40 22:42 11:18 22:45 10:11 21:20 12:09 22:20 12:47 23:24 13:23 00:39 13:08 01:47 13:56 03:45 15:26 04:50 16:06 04:30 17:42 04:25 18:32 04:06 12 10:35 23:11 12:17 23:20 11:11 21:58 13:07 23:20 13:31 ––:–– 13:57 01:44 13:45 02:50 14:46 04:38 16:21 05:25 17:01 04:58 18:41 ––:–– 19:34 ––:–– 13 11:31 23:41 13:19 ––:–– 12:12 22:41 14:00 ––:–– 14:10 00:32 14:31 02:49 14:26 03:52 15:40 05:27 17:17 05:57 17:56 05:26 19:42 05:31 20:34 05:39 14 12:28 ––:–– 14:22 00:00 13:14 23:31 14:48 00:25 14:46 01:40 15:07 03:54 15:10 04:52 16:35 06:10 18:12 ––:–– 18:53 ––:–– 20:43 06:10 21:30 06:36 15 13:28 00:12 15:26 00:47 14:15 ––:–– 15:31 01:34 15:21 02:47 15:45 04:58 15:59 05:50 17:31 ––:–– 19:07 06:55 19:50 06:23 21:44 06:55 22:19 07:39 16 14:30 00:46 16:28 01:42 15:12 00:28 16:10 02:43 15:55 03:54 16:28 06:00 16:51 ––:–– 18:27 07:23 20:02 07:23 20:49 06:55 22:41 07:47 23:03 08:46 17 15:35 01:25 17:26 02:44 16:05 01:32 16:47 03:53 16:31 05:00 17:15 ––:–– 17:46 07:30 19:22 07:55 20:58 07:51 21:49 07:31 23:33 08:45 23:43 09:54 18 16:41 02:10 18:18 03:53 16:53 02:40 17:23 05:02 17:09 ––:–– 18:06 07:57 18:42 08:12 20:17 08:24 21:55 08:21 22:49 08:11 04:39 ––:–– 05:19 ––:–– 19 17:47 03:02 19:05 ––:–– 17:36 03:52 17:59 ––:–– 17:50 07:11 19:00 08:48 19:38 08:49 21:11 08:52 22:54 08:54 23:48 08:58 00:20 10:54 00:18 12:09 20 18:48 04:03 19:47 06:19 18:16 ––:–– 18:36 07:18 18:35 08:14 19:55 09:34 20:34 09:22 22:07 09:20 23:54 09:31 04:50 ––:–– 01:02 12:02 00:52 13:15

21 19:44 ––:–– 20:25 07:31 18:53 06:15 19:16 08:24 19:24 09:13 20:51 10:14 21:28 09:53 23:03 09:49 05:06 ––:–– 00:44 10:51 01:40 13:10 01:25 14:22 22 20:33 06:22 21:01 08:40 19:29 07:25 19:59 09:28 20:16 10:07 21:47 10:49 22:23 10:21 04:44 ––:–– 00:55 11:03 01:35 11:56 02:16 14:18 01:59 15:28 23 21:16 07:34 21:36 09:48 20:06 08:33 20:45 10:29 21:11 10:55 22:42 11:22 23:18 10:49 00:02 10:54 01:54 12:00 02:21 13:04 02:50 15:26 02:36 16:35 24 21:55 08:45 22:12 10:53 20:44 09:39 21:35 11:25 22:06 11:38 23:37 11:51 05:21 ––:–– 01:02 11:34 02:49 13:03 03:03 14:14 03:24 16:35 03:16 17:41 25 22:30 09:54 22:50 11:56 21:25 10:43 22:28 12:16 23:02 12:16 06:02 ––:–– 00:15 11:48 02:04 12:20 03:40 14:12 03:41 15:25 04:01 17:44 04:01 18:44

26 23:05 10:59 23:31 12:56 22:08 11:44 23:22 13:01 23:57 12:50 00:32 12:48 01:13 12:21 03:06 13:14 04:27 15:24 04:17 16:35 04:40 18:52 04:51 19:42 27 23:39 12:03 06:40 ––:–– 22:55 12:41 06:34 ––:–– 06:42 ––:–– 01:29 13:18 02:14 12:58 04:06 14:16 05:08 16:37 04:53 17:46 05:23 19:57 05:45 20:33 28 06:18 ––:–– 00:14 14:48 23:45 13:34 00:17 14:17 00:52 13:50 02:27 13:50 03:16 13:42 05:01 15:25 05:47 17:49 05:29 18:56 06:11 20:59 06:43 21:19 29 00:14 14:05 07:04 ––:–– 01:12 14:50 01:48 14:19 03:28 14:25 04:20 14:33 05:52 16:37 06:24 19:01 06:08 20:06 07:04 21:54 07:41 21:58 30 00:52 15:03 00:37 15:04 02:08 15:20 02:44 14:48 04:31 15:07 05:23 15:33 06:37 17:51 07:00 20:11 06:49 21:13 08:00 22:43 08:39 22:32

31 01:33 15:59 01:31 15:42 03:42 15:19 06:23 16:39 07:18 19:03 07:35 22:16 09:36 23:03

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34 Lunar Occultations BAA Handbook 2019

SUN’S SELENOGRAPHIC COLONGITUDEDay Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 205.5 222.5 203.1 220.7 226.7 245.3 251.9 270.8 289.5 295.6 313.4 318.5 2 217.7 234.7 215.3 233.0 238.9 257.5 264.1 283.1 301.8 307.8 325.6 330.6 3 229.9 246.9 227.5 245.2 251.1 269.7 276.4 295.3 314.0 320.0 337.8 342.8 4 242.1 259.1 239.7 257.4 263.4 282.0 288.7 307.6 326.2 332.2 349.9 355.0 5 254.3 271.2 251.9 269.6 275.6 294.2 300.9 319.8 338.5 344.4 2.1 7.1

6 266.4 283.4 264.1 281.8 287.8 306.5 313.2 332.1 350.7 356.6 14.3 19.3 7 278.6 295.6 276.3 294.1 300.1 318.7 325.4 344.3 2.9 8.8 26.4 31.5 8 290.8 307.8 288.5 306.3 312.3 331.0 337.6 356.5 15.1 21.0 38.6 43.6 9 303.0 320.0 300.7 318.5 324.5 343.2 349.9 8.7 27.3 33.2 50.8 55.7 10 315.2 332.2 312.9 330.7 336.8 355.4 2.1 20.9 39.5 45.4 62.9 67.9 11 327.4 344.4 325.1 342.9 349.0 7.6 14.3 33.1 51.6 57.5 75.1 80.0 12 339.5 356.5 337.3 355.1 1.2 19.9 26.5 45.3 63.8 69.7 87.2 92.1 13 351.7 8.7 349.5 7.3 13.4 32.1 38.7 57.5 76.0 81.8 99.3 104.3 14 3.9 20.9 1.7 19.5 25.6 44.3 50.9 69.7 88.2 94.0 111.5 116.4 15 16.0 33.0 13.9 31.7 37.8 56.5 63.1 81.9 100.4 106.2 123.6 128.5

16 28.2 45.2 26.0 43.9 50.0 68.7 75.3 94.1 112.5 118.3 135.8 140.7 17 40.3 57.3 38.2 56.0 62.2 80.8 87.5 106.3 124.7 130.5 147.9 152.8 18 52.5 69.5 50.4 68.2 74.3 93.0 99.7 118.5 136.9 142.6 160.1 165.0 19 64.6 81.6 62.5 80.4 86.5 105.2 111.9 130.7 149.1 154.8 172.2 177.1 20 76.7 93.7 74.7 92.5 98.7 117.4 124.1 142.9 161.3 167.0 184.4 189.3

21 88.8 105.9 86.8 104.7 110.9 129.6 136.3 155.0 173.4 179.2 196.6 201.4 22 101.0 118.0 99.0 116.9 123.1 141.8 148.5 167.3 185.6 191.3 208.7 213.6 23 113.1 130.1 111.1 129.0 135.3 154.0 160.7 179.5 197.8 203.5 220.9 225.8 24 125.2 142.3 123.3 141.2 147.5 166.2 172.9 191.7 210.0 215.7 233.1 238.0 25 137.4 154.4 135.4 153.4 159.7 178.5 185.1 203.9 222.3 227.9 245.3 250.2

26 149.5 166.6 147.6 165.6 171.9 190.7 197.4 216.1 234.5 240.1 257.5 262.3 27 161.6 178.8 159.8 177.8 184.1 202.9 209.6 228.3 246.7 252.3 269.7 274.5 28 173.8 190.9 172.0 190.0 196.3 215.2 221.8 240.6 258.9 264.5 281.9 286.7 29 186.0 184.1 202.2 208.5 227.4 234.1 252.8 271.2 276.8 294.1 298.9 30 198.1 196.3 214.4 220.8 239.6 246.3 265.1 283.4 289.0 306.3 311.1

31 210.3 208.5 233.0 258.6 277.3 301.2 323.3

The Sun’s selenographic colongitude is numerically equal to the selenographic longitude of the morning terminator, measured towards celestial East from the mean centre of the disk. Its value is approximately 270° at New Moon, 0° at First Quarter, 90° at Full Moon, and 180° at Last Quarter, and should be quoted on observations. The IAU longitude of the visible morning or evening terminator, as appropriate, can be obtained from the Sun’s selenographic colongitude S as follows: Terminator S Longitude (IAU)New Moon to First Quarter Morning 270° to 360° 360°–S EastFirst Quarter to Full Moon Morning 0° to 90° S WestFull Moon to Last Quarter Evening 90° to 180° 180°–S EastLast Quarter to New Moon Evening 180° to 270° S–180° West

The hourly increase in S may be taken as 0.5°

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BAA Handbook 2019 Lunar Occultations 35

LUNAR OCCULTATIONSExcept near new and full Moon, occultations of all stars down to magnitude 6.0, visible from the three pairs of stations whose co–ordinates are tabulated below, are given in the following lists. ZC numbers refer to the Zodiacal Catalog (Astron. Papers of the American Ephemeris, X, part II, 1940).

Long. (λ) Lat. (φ) Long. (λ) Lat. (φ) ° ° ° ° Greenwich 0.0 +51.5 Edinburgh –3.2 +56.0

Sydney +151.2 –33.9 Melbourne +145.1 –37.9 Dunedin +170.5 –45.9 Wellington +174.8 –41.3

Phase (Ph.). The first letter indicates whether disappearance (D) or reappearance (R). The second letter indicates whether the limb is dark (D) or bright (B).Column 7 gives the percentage Illumination of the Moon.CA is the cusp angle of the star, measured to the celestial east (anticlockwise) from the northernmost point of the Moon’s limb.The time (T) of occultation at a place Δλ degrees east and Δφ degrees north of one of the stations for which a prediction is given may be found from:

T = predicted time + a Δλ + b Δφfor which the coefficients a and b are given in the table in minutes. If the observer is west of the station, Δλ is taken as negative: similarly Δφ is negative if the observer is south of the station. For distances up to 500 km the error will not usually exceed 2 minutes.

If the observer is at a place between two standard stations, for both of which the coefficients a and b are given, a better result can be obtained by using the values of a and b for a latitude midway between that of the observer and the nearer station. If φ1, a1, b1 apply to this station, and (φ2, a2,b2 to the more distant, and φ is the latitude of the observer, then

Observers should note that these calculations are prone to error propagation and are best done using a spreadsheet or appropriate app. Suitable support is available on the BAA website.

Notes: Predictions have been prepared using Occult 4 software.

For stars not identified by a Greek letter, Flamsteed number or variable star designation, the HIP catalogue number is provided.

When an occultation is given for one station of a pair, but not the other, the exclusion indicates the event is probably not observable at that station due to a miss, Moon elevation too low, sky too bright, or the event occurs on the bright limb. Observability is determined by a sophisticated algorithm in ‘Occult 4’.

A more detailed list of occultations is printed monthly in the Lunar Section Circulars, available on the BAA web site. Alternatively, keen observers may like to download Occult to generate predictions for their site, from: http://www.lunar-occultations.com/iota/occult4.htm (free for non–commercial use).

Further links can be found on the Internet Resources Page.

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36 Lunar Occultations BAA Handbook 2019

Lunar Occultations LUNAR OCCULTATIONS GREENWICH EDINBURGH E 0.0º N 51.5º W 3.2º N 56.0º

Date Star V Ph. Ill. of2019 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

Jan. 1 2128 13 Lib 5.8 RD –22 3 50.7 +0.3 +0.4 70N 3 51.7 +0.1 +0.3 59N 2 2271 θ Lib 4.1 DB –13 8 10.5 +0.9 –0.1 –61S 2 2271 θ Lib 4.1 RD –13 9 25.0 +1.8 +0.0 67S 9 19.9 +1.5 +0.1 70S 10 3356 74 Aqr 5.8 DD +18 17 46.6 +0.8 +0.1 63N 17 45.8 +0.6 +0.5 48N 15 405 μ Cet 4.3 DD +64 16 54.4 –1.4 +5.5 8N 15 405 μ Cet 4.3 RB +65 17 13.8 +3.6 –2.7 –23N 19 894 χ1 Ori 4.4 DD +93 2 31.1 +0.4 –1.7 73S 2 22.5 +0.5 –1.5 82S 20 1077 ζ Gem 4.0 DD +98 5 1.6 –0.4 –2.4 34S 4 52.2 –0.2 –2.2 42S 30 2361 χ Oph 4.2 RD –26 5 58.0 +1.2 +0.6 83N 5 57.4 +1.0 +0.7 79N 31 2498 ξ Oph 4.4 DD –18 6 44.9 –3.3 –6.5 1S 31 2498 ξ Oph 4.4 RD –18 6 53.2 +5.4 +8.0 15SFeb. 2 Saturn 0.6 RD –6 6 31.6 +0.4 +0.7 45N 7 3428 ψ3 Aqr 5.0 DD +6 12 12.7 +1.2 +1.6 63N 11 364 ξ2 Cet 4.3 DD +37 15 48.5 +1.5 +0.9 80S 15 49.0 +1.2 +1.2 88N 11 364 ξ2 Cet 4.3 RB +37 17 2.2 +1.1 +1.5 –60S 17 4.0 +1.1 +1.0 –73S 13 650 63 Tau 5.6 DD +60 23 18.9 –0.1 –5.3 21S 23 1.3 +0.4 –3.0 43S 14 764 104 Tau 4.9 DD +69 16 11.4 +1.6 –0.5 34S 18 1310 Δ Cnc 3.9 DD +97 5 53.6 –0.4 –1.6 63S 5 47.4 –0.3 –1.7 23 1950 80 Vir 5.7 RD –82 6 57.8 +0.7 –1.6 86NMar. 13 730 97 Tau 5.1 DD +42 17 12.3 +0.9 +3.3 28N 13 730 97 Tau 5.1 RB +42 17 58.6 +1.9 –2.5 –45N 20 1625 HIP 54863 5.8 DD +99 4 8.1 +0.0 –2.2 61S 3 58.3 +0.1 –2.1 64S 26 2401 HIP 81754 5.6 RD –70 3 31.5 +3.7 +4.2 22SApr. 7 405 μ Cet 4.3 DD +5 11 34.9 +1.7 +0.5 65S 11 34.3 +1.2 +1.1 78S 7 405 μ Cet 4.3 RB +5 12 26.9 +0.5 +2.8 –23S 12 35.5 +0.7 +2.0 –38S 9 718 HIP 22176 6.0 DD +20 21 32.5 +0.4 +0.0 42N 21 31.8 +0.7 +0.7 28N 9 730 97 Tau 5.1 DD +21 23 35.1 +0.0 –0.1 37N 12 1129 63 Gem 5.3 DD +48 14 26.6 +0.2 +3.2 29N 14 1418 8 Leo 5.7 DD +72 19 5.4 +1.6 +1.3 52N 19 8.6 +1.5 +2.4 35N 16 1576 37 Leo 5.3 DD +85 2 38.0 +0.1 –1.7 87N 2 29.9 +0.2 –1.7 84NMay 1 3536 30 Psc 4.4 RD –13 7 20.4 +0.3 +2.8 33S 6 648 δ1 Tau 3.8 DD +3 17 6.0 +0.8 –1.5 88S 16 57.6 +0.8 –1.1 79N 6 658 68 Tau 4.3 DD +4 18 41.4 +0.8 +1.1 22N 9 1129 63 Gem 5.3 DD +26 21 30.0 +0.5 –0.9 55N 21 24.1 +0.6 –0.8 48N 19 2401 HIP 81754 5.6 RD –99 22 17.5 +1.1 +1.0 80N Jun. 5 1047 36 Gem 5.3 DD +6 12 11.6 +1.4 –0.1 71S 12 8.7 +1.1 +0.6 87S 9 1504 37 Leo 5.4 DD +36 0 5.4 –0.1 –1.2 45N 25 5 33 Psc 4.6 RD –53 1 4.6 +0.4 +1.6 63N 1 10.9 +0.3 +1.7 58N 26 118 20 Cet 4.8 RD –43 2 30.5 +0.3 +2.5 44S 2 40.0 +0.3 +2.2 51S 28 364 ξ2 Cet 4.3 DB –24 3 9.1 +0.3 +1.7 –77S 3 16.2 +0.2 +1.8 –83S 28 364 ξ2 Cet 4.3 RD –24 4 10.2 +0.4 +2.1 71S 4 18.0 +0.4 +2.0 78S 30 648 δ1 Tau 3.8 DB –7 9 25.3 +1.4 +0.7 –88S 9 25.5 +1.1 +1.2 –77N

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BAA Handbook 2019 Lunar Occultations 37

Jun. 30 648 δ1 Tau 3.8 RD –7 10 41.4 +1.4 +0.4 84S 10 37.6 +1.3 –0.1 81N 30 653 64 Tau 4.8 RD –7 11 2.9 +1.1 +2.3 42S 11 6.4 +1.1 +1.0 61S 30 658 68 Tau 4.3 DB –7 11 13.3 +1.2 +1.7 –49N 30 658 68 Tau 4.3 RD –7 12 8.3 +1.3 –2.3 47N 11 49.3 +1.5 –4.9 22NJul 9 1950 80 Vir 5.7 DD +56 23 42.7 +0.3 –1.9 74S 23 33.2 +0.3 –1.9 78S 15 2595 HIP 88298 5.7 DD +96 0 30.5 +1.4 –1.0 87S 0 22.2 +1.2 –0.8 88N 16 2754 HIP 92931 5.9 DD +99 0 15.8 +1.5 –0.1 73N 0 11.0 +1.3 +0.0 68N 28 730 97 Tau 5.1 RD –18 7 59.6 +1.0 +2.5 42S Aug 11 2706 HIP 91405 5.8 DD +88 22 37.8 +1.7 –1.5 24S 24 648 δ1 Tau 3.8 DB –45 2 43.6 +0.7 +1.7 –84N 2 50.0 +0.5 +1.9 –73N 24 648 δ1 Tau 3.8 RD –44 3 53.1 +1.0 +1.7 75S 3 57.2 +0.9 +1.5 87S 24 653 64 Tau 4.8 DB –44 3 26.9 +1.7 +0.1 –47S 3 25.4 +1.1 +1.0 –63S 24 653 64 Tau 4.8 RD –44 4 9.8 +0.2 +3.5 26S 4 21.4 +0.5 +2.5 44S 24 658 68 Tau 4.3 DB –44 4 23.4 +0.8 +2.3 –50N 4 33.0 +0.4 +2.8 –34N 24 658 68 Tau 4.3 RD –44 5 29.7 +1.7 +0.1 71N 5 23.4 +1.7 –0.5 53N 27 1110 δ Gem 3.5 DB –15 4 5.1 –0.9 +4.7 –9N 27 1110 δ Gem 3.5 RD –14 4 25.0 +1.6 –2.0 30N Sep 11 3078 η Cap 4.9 DD +91 0 7.9 +1.0 –0.6 85N 0 2.7 +0.8 –0.4 74N 14 5 33 Psc 4.6 RD –99 21 14.6 +0.8 +2.0 34S 21 21.0 +0.7 +1.9 39S 20 730 97 Tau 5.1 RD –62 22 49.1 –0.7 +2.5 19S 21 765 106 Tau 5.3 RD –59 7 55.3 +0.5 –7.0 21N 23 1047 36 Gem 5.3 RD –39 1 45.3 –0.5 +3.3 19SOct 19 847 ζ Tau 3.0 DB –75 0 23.3 +1.3 +0.4 –58S 0 23.7 +0.9 +1.1 –73S 19 847 ζ Tau 3.0 RD –75 1 12.9 +0.4 +3.1 32S 1 23.0 +0.6 +2.3 49S 22 1277 η Cnc 5.3 RD –43 1 31.5 +0.4 +1.0 85N 1 34.0 +0.4 +0.7 71NNov 1 2692 24 Sgr 5.5 DD +24 17 32.3 +1.6 –1.3 56S 17 22.8 +1.4 –0.9 62S 15 928 TV Gem 5.9 RD –89 20 6.0 +0.1 +1.0 68N 20 10.0 +0.1 +0.9 56N 15 946 η Gem 3.5 DB –88 21 52.1 –1.1 +4.4 –7N 15 946 η Gem 3.5 RD –88 22 13.5 +1.8 –1.4 34N 16 976 μ Gem 2.9 DB –87 1 31.4 +1.5 +0.6 –87N 1 31.3 +1.2 +1.2 –72N 16 976 μ Gem 2.9 RD –87 2 48.8 +1.6 +0.4 76S 2 44.8 +1.4 +0.0 89N 28 Jupiter –1.7 RB +4 10 29.1 +0.8 +0.8 –66N Dec 5 5 33 Psc 4.6 DD +63 18 5.6 +0.9 +1.7 55N 18 11.0 +0.6 +1.8 44N 5 5 33 Psc 4.6 RB +64 19 16.8 +1.9 +0.0 –67N 19 10.4 +1.9 –0.2 –54N 5 18 HIP 840 5.8 DD +64 21 36.3 +1.5 –1.4 63S 21 27.5 +1.2 –0.7 79S 13 928 TV Gem 5.9 RD –99 5 9.5 +0.8 –0.6 52S 5 3.7 +0.7 –0.9 62S 13 946 η Gem 3.5 DB –99 6 44.3 +0.6 –0.1 –32N 6 42.7 +0.9 +0.6 –20N 13 946 η Gem 3.5 RD –99 7 16.6 –0.7 –2.6 40N 7 5.8 –0.9 –3.4 29N 14 1078 44 Gem 6.0 RD –96 3 8.9 +1.5 +0.0 64S 3 3.6 +1.3 –0.4 76S 15 1224 μ Cnc 5.3 RD –90 4 12.2 +1.4 –0.8 79S 4 4.4 +1.2 –0.9 89S 18 1702 ν Vir 4.0 RD –52 23 37.7 –0.1 +1.1 78S 23 42.4 –0.1 +0.9 88N

Lunar Occultations LUNAR OCCULTATIONS GREENWICH EDINBURGH E 0.0º N 51.5º W 3.2º N 56.0º

Date Star V Ph. Ill. of2019 ZC Name Moon UT a b CA UT a b CA % h m m/° m/° ° h m m/° m/° °

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38 Lunar Occultations BAA Handbook 2019

Jan. 11 3419 ψ1 Aqr 4.2 DD +22 4 14.8 +4.3 –5.9 30S 11 3419 ψ1 Aqr 4.2 RB +22 4 48.5 –0.6 +7.3 –13S 14 249 ν Psc 4.5 DD +51 10 29.6 +2.0 +1.0 68S 10 13.1 +2.2 +0.8 67S 14 249 ν Psc 4.5 RB +52 11 39.2 +0.9 +2.5 –57S 11 23.3 +1.0 +2.5 –53S 19 976 μ Gem 2.9 DD +96 12 58.5 +2.3 +4.9 15N 12 35.1 +1.7 +1.8 31N 19 976 μ Gem 2.9 RB +96 13 22.3 +1.6 –4.2 –19N 13 20.3 +2.0 –1.5 –38N 21 1277 eta Cnc 5.3 RD –100 13 10.2 +2.0 –0.2 84S 12 59.6 +1.7 –0.2 76S 24 1689 ω Vir 5.2 RD –83 15 2.3 +1.0 –2.6 42N 15 4.7 +1.1 –2.1 57N 25 1813 FW Vir 5.7 RD –73 19 10.1 +1.9 –0.6 85N 18 58.7 +2.3 +0.0 74SFeb. 1 2708 HIP 91438 5.9 RD –8 18 18.2 +0.1 –1.3 79N 18 22.2 +0.1 –1.0 84S 2 2759 ξ2 Sgr 3.5 DB –7 5 1.8 +0.3 +1.5 –79N 4 52.9 +0.6 +1.5 –83N 2 2759 ξ2 Sgr 3.5 RD –6 6 3.7 +0.0 +1.2 88S 5 58.3 +0.1 +1.4 85S 11 327 ξ1 Cet 4.4 DD +34 10 2.8 +1.1 +2.8 45N 9 45.3 +1.2 +2.5 50N 11 327 ξ1 Cet 4.4 RB +35 10 59.4 +0.9 +0.7 –54N 10 49.4 +1.2 +1.0 –62N 12 454 HIP 14439 5.6 DD +45 12 20.4 +0.6 +1.4 86S 12 10.6 +0.8 +1.3 76S 24 2133 ξ Librae 5.5 RD –67 19 53.3 +2.1 –0.4 84N 19 40.2 +2.3 +0.3 76SMar. 15 976 μ Gem 2.9 DD +60 6 21.5 +1.2 +0.2 54N 6 15.2 +0.9 –0.2 57N 15 976 μ Gem 2.9 RB +60 7 35.1 +2.3 –0.9 –77N 7 26 +2.0 –1.0 –80N 17 1277 eta Cnc 5.3 DD +81 10 3.5 +1.8 –2.2 46S 10 4.1 +1.6 –3.6 28S 20 1702 ν Vir 4.0 DD +100 17 35.2 +0.6 –0.5 72N 17 35.6 +0.4 –1.3 87S 21 1813 FW Vir 5.7 RD –99 15 56.3 +1.3 –1.2 30N 28 2746 33 Sag 5.7 RD –45 14 10.2 –0.2 –1.2 77N 14 15.5 –0.2 –0.9 87S 28 2779 ο Sgr 3.8 DB –44 19 1.4 +2.1 –1.8 –61S 19 0.2 +1.4 –3.1 –41S 28 2779 ο Sgr 3.8 RD –43 20 30.9 +2.6 +1.1 75S 20 9.7 +2.5 +1.8 58SApr. 1 3275 45 Aqr 6.0 RD –11 17 31.6 –0.4 –2.1 38N 11 946 eta Gem 3.5 DD +35 10 52.5 +1.0 +1.2 83N 10 42.3 +1.0 +0.8 81S 20 2133 ξ Lib 5.5 RD –98 15 3.5 +1.2 –2.4 30N 21 2291 49 Lib 5.5 RD –93 20 38.4 +0.7 +1.7 73S 25 Saturn 0.5 DB –63 12 30.2 –0.4 –1.4 –61S 12 40.1 –0.7 –1.9 –43S 25 Saturn 0.5 RD –62 13 25.6 +0.2 –0.8 87S 13 26.4 +0.3 –0.4 68S 27 3113 30 Cap 5.4 RD –42 18 24.6 +1.9 +1.2 66S 18 7.1 +1.7 +2.3 46SMay 2 170 33 Cet 6.0 RD –5 19 2.3 +0.4 –2.4 34N 19 8.2 +0.2 –1.5 51N 15 1813 FW Vir 5.7 DD +85 8 9.0 +0.3 –3.4 34S 18 2223 γ Lib 3.9 DD +100 18 15.5 +0.7 +1.1 15N 18 6.5 +1.0 +0.7 27N 21 2635 14 Sgr 5.5 RD –92 14 24.3 +1.7 –2.0 58N 14 20.6 +1.6 –1.3 77N 22 2779 ο Sgr 3.8 DB –86 10 56.7 +0.2 –0.4 –72N 22 2779 ο Sgr 3.8 RD –86 11 47.6 –0.1 –2.2 44N 11 55.5 +0.0 –1.7 63N 22 Saturn 0.3 DB –83 23 13.5 +0.0 +1.2 –87S 23 8.0 +0.2 +1.3 –84S 23 Saturn 0.3 RD –83 0 5.5 –0.3 +1.5 80S 25 3171 γ Cap 3.7 RD –60 12 46.7 –0.1 –0.6 88N 25 3190 δ Cap 2.9 DB –59 15 49.7 +1.5 +2.9 –40N 15 35.7 +1.1 +0.6 –63N 25 3190 δ Cap 2.9 RD –59 16 37.5 +1.7 –4.2 31N 16 40.4 +1.4 –2.3 51N 27 3425 ψ 2 Aqr 4.4 RD –40 15 12.4 +0.3 +0.1 78S 15 9.5 +0.2 +0.7 59S 30 249 ν Psc 4.5 DB –14 18 44.8 +0.2 +1.6 –47N 18 39.1 +0.2 +0.8 –59N 30 249 ν Psc 4.5 RD –14 19 38.3 +1.6 –1.8 53N 19 36.6 +1.1 –1.4 61NJun. 10 1689 ω Vir 5.2 DD +52 12 15.1 +2.3 +4.4 29N 15 2291 49 Lib 5.5 DD +96 11 19.1 +1.5 –2.3 65S 11 23.7 +0.6 –3.5 41S 21 3171 γ Cap 3.7 RD –81 23 22.4 –0.8 +3.1 29S 23 14.0 –0.8 +3.5 25S 22 3288 50 Aqr 5.8 RD –73 21 34.9 +0.9 +2.3 66S

Lunar Occultations LUNAR OCCULTATIONS SYDNEY MELBOURNE E 151.2º S 33.9º E 145.1º S 37.9º

Date Star V Ph. Ill. of2019 ZC Name Moon UT a b CA UT a b CA % h m m/° m/° ° h m m/° m/° °

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BAA Handbook 2019 Lunar Occultations 39

27 322 64 Cet 5.6 RD –27 20 7.3 +5.1 –5.1 31N 19 59.1 +3.6 –4.0 35N 27 327 ξ1 Cet 4.4 DB –26 21 3.8 –2.8 +7.5 –4N 20 51.0 –3.1 +7.9 –3N 27 327 ξ1 Cet 4.4 RD –26 21 27.5 +6.5 –5.3 28N 21 11.1 +6.5 –6.5 25NJul. 11 2133 ξ Lib 5.5 DD +72 13 48.0 +1.1 +5.4 24N 18 3113 30 Cap 5.4 RD –97 19 56.3 +0.2 +2.2 59S 19 45.6 +0.4 +2.3 58S 27 654 HIP 20614 6.0 RD –22 20 17.3 +2.9 –2.0 53N 20 9.1 +2.4 –2.0 54N 27 668 ε Tau 3.5 DB –22 21 23.0 +2.1 +0.3 –81N 21 10.7 +1.8 +0.0 –81N 27 668 ε Tau 3.5 RD –22 22 50.8 +2.2 +0.9 80S 22 34.8 +2.0 +0.6 77SAug. 8 2223 γ Lib 3.9 DD +58 13 18.4 +0.5 +0.9 83N 13 11.3 +0.8 +0.6 86S 8 2223 γ Lib 3.9 RB +59 14 15.4 +0.3 +1.0 –84S 11 2635 14 Sag 5.5 DD +85 11 57.8 +1.9 +8.2 22N 11 24.5 +2.5 +2.7 49N 12 Saturn 0.2 DD +91 8 34.0 +0.4 –4.2 24S 12 Saturn 0.2 RB +91 9 22.7 +2.7 +2.3 –48S 15 3171 γ Cap 3.7 DD –100 10 0.7 +1.6 +3.2 60N 9 47.1 +0.9 +0.5 37N 15 3171 γ Cap 3.7 RD –100 10 41.4 +1.2 –4.8 62S 10 47.7 +1.1 –2.4 40S 15 3190 δ Cap 2.9 DD –100 15 6.8 +1.3 +2.9 15N 14 47.0 +1.6 +2.5 11N 15 3190 δ Cap 2.9 RD –100 16 23.2 +2.1 +0.8 51S 16 6.6 +2.3 +0.7 50S 16 3288 50 Aqr 5.8 RD –99 8 53.0 –0.1 –2.2 61N 17 3419 ψ1 Aqr 4.2 RD –96 12 9.9 +1.4 –4.2 41N 17 3425 ψ2 Aqr 4.4 DB –96 12 24.0 +1.5 –0.3 –84N 17 3425 ψ2 Aqr 4.4 RD –96 13 49.5 +1.9 +0.9 68S 13 35.7 +1.5 +0.9 61S 22 454 HIP 14439 5.6 RD –59 14 55.5 +0.5 +0.0 71S 14 53.0 +0.3 +0.1 65SSep. 8 2779 ο Sgr 3.8 DD +74 17 7.1 –0.8 +2.1 44N 12 3288 50 Aqr 5.8 DD +98 16 59.4 +1.8 –0.1 28S 16 47.5 +2.2 –0.1 28S 21 817 114 Tau 4.9 RD –55 14 41.0 +0.8 –1.6 73N Oct. 2 2223 γ Lib 3.9 DD +16 3 6.9 +4.1 +2.6 41N 2 49.5 +1.8 –0.6 72N 2 2223 γ Lib 3.9 RB +16 3 37.1 –0.9 –6.1 –4N 3 50.5 +0.8 –2.8 –37N 2 2247 eta Lib 5.4 DD +17 8 34.7 +1.0 +2.9 48N 8 17.8 +1.4 +1.8 66N 2 2247 eta Lib 5.4 RB +17 9 21.7 +1.1 –1.6 –39N 9 19.4 +1.1 –0.6 –54N 3 2361 χ Oph 4.2 DD +24 0 53.0 –1.5 –4.8 5S 4 2547 58 Oph 4.9 DD +37 12 5.3 +0.7 +0.1 60S 12 0.1 +1.0 –0.1 54S 4 2547 58 Oph 4.9 RB +38 12 48.8 –0.3 +2.3 –49S 8 3113 30 Cap 5.4 DD +76 13 33.1 +0.4 +2.7 54N 13 19.1 +0.6 +2.8 55N 15 404 85 Ari 5.2 RD –97 18 50.2 +1.2 +0.4 58N 18 39.2 +1.5 +0.8 66N 18 792 109 Tau 5.0 RD –78 18 35.4 +2.3 +0.9 78S 18 18.6 +2.2 +0.7 73S 19 929 3 Gem 5.8 RD –70 14 31.1 +0.5 +0.0 53S 26 1773 16 Vir 5.0 RD –6 3 52.1 +1.4 +2.5 34S 31 2498 ξ Oph 4.4 DD +14 11 45.5 +0.2 +0.0 52SNov. 7 3425 ψ2 Aqr 4.4 DD +77 8 12.3 +1.3 +2.4 52N 7 56.7 +1.3 +1.4 61N 7 3425 ψ2 Aqr 4.4 RB +77 9 29.2 +3.0 –0.4 –62N 9 14.8 +2.4 –0.5 –67N 13 593 HIP 18735 5.9 RD –99 11 50.4 +3.3 –3.6 55N 11 46.3 +2.5 –3.2 58N 14 752 ι Tau 4.6 RD –95 17 41.1 +1.9 +1.4 70S 17 23.2 +2.0 +1.4 62S 16 1050 HIP 32968 5.7 RD –83 13 19.4 –0.2 +1.5 20S 21 1701 ξ Vir 4.8 RD –29 17 1.8 +0.7 –6.7 15NDec. 3 3288 50 Aqr 5.8 DD +43 14 12.0 –0.5 +2.4 44N 15 1308 γ Cnc 4.7 DB –86 17 33.4 +1.6 –1.3 –51S 15 1308 γ Cnc 4.7 RD –86 18 43.5 +2.3 +1.1 66S 18 22.3 +2.9 +1.8 44S 18 1689 ω Vir 5.2 RD –54 22 20.0 +1.9 +1.3 60S 23 2291 49 Lib 5.5 RD –7 18 35.0 –0.1 –2.0 60N 18 42.9 –0.1 –1.7 74N

Lunar Occultations LUNAR OCCULTATIONS SYDNEY MELBOURNE E 151.2º S 33.9º E 145.1º S 37.9º

Date Star V Ph. Ill. of2019 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

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40 Lunar Occultations BAA Handbook 2019

Jan. 14 249 ν Psc 4.5 DD +52 10 56.3 +1.3 –1.5 15S 10 59.0 +0.8 +0.1 31S 19 976 μ Gem 2.9 DD +96 13 9.5 +1.7 +1.8 44N 13 29.6 +2.5 +3.8 25N 19 976 μ Gem 2.9 RB +96 13 57.2 +0.6 –0.1 –41N 13 55.5 –0.2 –2.0 –19N 21 1277 η Cnc 5.3 RD –100 13 45.7 +1.9 +0.8 72S 13 57.5 +1.9 +0.7 85S 24 1689 ω Vir 5.2 RD –83 15 47.1 +0.9 –1.7 43N 15 39.7 +0.2 –3.0 22NFeb. 11 322 64 Cet 5.6 DD +34 8 45.1 +1.1 +1.6 83S 8 57.0 +1.0 +1.7 88S 11 327 ξ1 Cet 4.4 DD +34 9 52.4 +0.6 +2.0 73N 10 4.6 +0.5 +2.2 65N 28 2638 15 Sgr 5.3 RD –29 13 35.0 –0.3 –1.3 85N 13 27.3 –0.3 –1.4 73NMar. 1 2797 π Sgr 2.9 RD –21 14 51.4 +0.0 –1.1 87S 14 45.4 –0.1 –1.3 79N 13 668 ε Tau 3.5 DD +38 8 4.6 +1.5 +3.0 23N 13 668 ε Tau 3.5 RB +38 8 37.9 +1.0 –0.5 –30N 15 976 μ Gem 2.9 DD +59 6 56.7 +1.8 –0.4 88S 7 3.9 +2.0 –0.1 87N 15 976 μ Gem 2.9 RB +60 8 16.0 +1.8 +0.5 –77S 8 26.5 +1.9 +0.6 –85S 17 1277 η Cnc 5.3 DD +81 10 48.1 +0.6 –1.4 34S 10 46.8 +1.0 –0.7 52S 27 2633 μ Sgr 3.8 DB –53 21 17.0 +1.0 +2.7 –55N 21 34.6 +0.5 +3.5 –41N 27 2633 μ Sgr 3.8 RD –53 22 19.1 +1.2 +0.3 57N 22 24.3 +1.4 –0.5 45N 28 2746 33 Sgr 5.7 RD –45 14 29.3 +0.5 –1.4 85N 14 24.2 +0.5 –1.7 70N 28 2779 ο Sgr 3.8 DB –44 20 15.4 +2.9 –4.5 –26S 28 2779 ο Sgr 3.8 RD –43 20 53.1 +0.6 +6.1 25SApr. 1 3275 45 Aqr 6.0 RD –11 17 50.5 +0.6 –2.0 54N 17 41.6 +0.6 –3.2 33N 12 1078 44 Gem 6.0 DD +44 6 37.0 +0.7 –8.3 10S 6 29.6 +1.7 –1.8 34S 13 1224 μ Cnc 5.3 DD +56 7 28.4 +1.3 –1.4 39S 7 28.7 +1.5 –1.0 52S 20 2133 ξ Lib 5.5 RD –98 15 49.1 +1.1 –1.5 28N 25 Saturn 0.5 DB –63 12 47.7 +0.0 –2.2 –50S 12 39.4 +0.3 –1.7 –67S 25 Saturn 0.5 RD –62 13 47.0 +1.0 –0.6 74S 13 47.3 +1.0 –1.1 88NMay 2 170 33 Cet 6.0 DB –5 18 20.8 +0.5 –0.3 –89S 2 170 33 Cet 6.0 RD –5 19 27.7 +0.7 –0.2 87S 15 1813 FW Vir 5.7 DD +85 8 52.2 +0.4 –2.6 36S 8 44.6 +1.0 –2.0 56S 18 2223 γ Lib 3.9 DD +100 18 19.6 +0.4 –0.3 66N 18 20.6 +0.2 +0.1 54N 21 2635 14 Sgr 5.5 RD –92 15 13.7 +1.9 +0.2 87N 15 21.9 +2.1 –0.4 71N 22 2779 ο Sgr 3.8 DB –86 11 14.9 +0.7 –1.0 –83N 11 16.0 +1.2 –0.1 –64N 22 2779 ο Sgr 3.8 RD –86 12 20.3 +0.8 –2.1 57N 12 11.8 +0.6 –3.0 38N 22 Saturn 0.3 DB –83 23 5.4 +0.1 +0.2 –35S 25 3171 γ Cap 3.7 DB –61 12 1.9 –0.2 –2.0 –51S 11 53.8 +0.0 –1.4 –69S 25 3171 γ Cap 3.7 RD –60 12 56.6 +0.6 –0.2 69S 12 57.0 +0.6 –0.7 87S 25 3190 δ Cap 2.9 DB –59 16 8.1 +1.6 –0.2 –90N 16 16.6 +1.8 +0.7 –76N 25 3190 δ Cap 2.9 RD –59 17 34.4 +1.8 +0.5 89S 17 45.1 +2.2 +0.3 80N 27 3419 ψ1 Aqr 4.2 RD –41 14 31.5 +0.4 –1.0 81N 14 27.7 +0.5 –1.5 64N 27 3425 ψ2 Aqr 4.4 DB –41 14 45.6 +0.3 –6.5 –15S 14 30.0 +0.5 –2.5 –44S 27 3425 ψ2 Aqr 4.4 RD –40 15 7.7 +0.6 +5.0 23S 15 22.2 +0.8 +1.4 51S 30 249 ν Psc 4.5 DB –14 18 57.2 +1.3 –1.0 –72S 18 59.4 +1.4 –0.5 –81S 30 249 ν Psc 4.5 RD –14 20 6.9 +1.0 +0.9 63S 20 15.9 +1.3 +1.0 69SJun. 9 1544 46 Leo 5.4 DD +38 5 42.2 +1.5 –0.8 80S 5 46.4 +1.8 –0.4 87N 10 1689 ω Vir 5.2 DD +52 12 18.3 +0.5 +2.7 40N 14 2133 ξ Lib 5.5 DD +89 6 4.9 –0.1 –2.9 36S 5 53.0 +0.2 –2.5 52S 14 2141 18 Lib 5.9 DD +90 7 4.9 +6.2 +6.3 10N 15 2291 49 Lib 5.5 DD +96 12 14.1 +1.2 –2.7 45S 12 11.3 +1.6 –1.3 67S 21 3113 30 Cap 5.4 RD –84 9 58.5 +0.2 –0.7 80S 9 55.2 +0.2 –1.1 83N

Lunar Occultations LUNAR OCCULTATIONS DUNEDIN WELLINGTON E 170.5º S 45.9º E 174.8º S 41.3º

Date Star V Ph. Ill. of2019 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

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BAA Handbook 2019 Lunar Occultations 41

LUNAR OCCULTATIONS DUNEDIN WELLINGTON E 170.5º S 45.9º E 174.8º S 41.3º

Date Star V Ph. Ill. of2019 ZC Name Moon UT a b CA UT a b CA % h m m/º m/º º h m m/º m/º º

Jun. 27 327 ξ1 Cet 4.4 RD –26 22 15.9 +1.5 +1.4 88S 22 29.1 +1.6 +1.5 89NJul. 11 2133 ξ Lib 5.5 DD +72 13 41.5 +0.2 +1.5 68N 13 49.8 +0.0 +1.9 54N 19 3190 δ Cap 2.9 RD –94 7 43.2 –0.3 –1.1 82N 7 36.1 –0.3 –1.4 66N 27 668 68 Tau 3.5 DB –22 22 12.5 +1.9 +0.5 –66S 27 668 68 Tau 3.5 RD –22 23 7.6 +1.4 +1.9 52S 23 22.7 +1.5 +1.9 61SAug. 8 2223 γ Lib 3.9 DD +58 13 24.3 +0.4 –0.9 39S 13 23.1 +0.2 –0.3 54S 11 2635 14 Sgr 5.5 DD +85 11 58.2 +1.4 +1.2 86N 12 10.7 +1.2 +1.7 74N 15 3171 γ Cap 3.7 DD –100 10 16.5 +1.5 –0.2 15N 10 24.8 +1.7 +0.9 30N 15 3171 γ Cap 3.7 RD –100 11 40.4 +1.9 +0.0 6S 11 48.4 +2.3 –0.4 18S 15 3190 δ Cap 2.9 DB –100 15 16.0 +1.6 +1.1 –46N 15 28.0 +1.5 +1.3 –41N 15 3190 δ Cap 2.9 RB –100 16 21.9 +0.4 +2.5 –2S 15 3190 δ Cap 2.9 RD –100 16 34.6 +0.3 +2.4 2S 16 3288 50 Aqr 5.8 RD –99 9 20.9 +0.8 –1.1 84S 9 18.3 +1.0 –1.7 80N 17 3419 ψ1 Aqr 4.2 DB –96 11 46.0 +1.3 +0.2 –69N 11 54.8 +1.4 +1.1 –57N 17 3419 ψ1 Aqr 4.2 RD –96 13 8.4 +1.8 +0.2 84S 13 17.9 +2.2 +0.2 88NSep. 5 2291 49 Lib 5.5 DD +40 5 45.9 +1.6 –1.0 74S 5 51.1 +2.0 –0.1 87N 8 2725 28 Sgr 5.4 DD +72 7 8.8 +1.4 –3..9 29S 7 2.6 +1.9 –2.1 52S 16 192 89 Psc 5.1 RD –95 13 26.9 +2.8 –1.6 57N 13 32.3 +3.9 –2.4 49N 20 668 ε Tau 3.5 RD –66 12 33.0 +0.2 +0.0 54S 21 817 114 Tau 4.9 RD –55 15 3.7 +0.6 –0.1 48S 15 6.4 +0.8 +0.0 54SOct. 2 2223 γ Lib 3.9 DD +16 3 45.1 +2.4 +1.5 55N 2 2223 γ Lib 3.9 RB +16 4 36.6 +1.0 –2.8 –29N 2 2247 η Lib 5.4 DD +17 8 30.8 +0.5 +0.8 80S 8 36.9 +0.3 +1.0 88N 3 2361 χ Oph 4.2 DD +24 1 8.0 +0.2 –3.0 31S 8 3113 30 Cap 5.4 DD +76 13 19.5 +0.5 +1.6 76S 13 28.7 +0.4 +1.5 79S 18 766 105 Tau 5.8 RD –80 11 58.6 +1.9 –3.2 47N 19 916 1 Gem 4.3 RD –71 12 13.8 +0.9 –1.7 76N 21 1221 9 Cnc 6 RD –49 14 47.1 +0.7 –1.1 67S 14 45.3 +0.9 –1.1 73S 23 1484 η Leo 3.5 RD –26 15 58.3 +9.9 +9.9 14N 29 2291 49 Lib 5.5 DD +5 23 59.1 +2.5 +0.9 50N Nov. 2 2747 ν1 Sgr 4.9 DD +28 0 44.1 +0.2 –2.6 43S 0 35.5 +0.6 –1.9 61S 2 2749 ν2 Sgr 5 DD +28 1 6.3 +0.7 –1.8 67S 1 3.0 +1.1 –1.2 84S 2 Saturn 0.6 DD +29 7 47.1 +0.9 +2.5 60N 8 2.5 +0.5 +2.9 49N 2 Saturn 0.6 RB +30 8 51.0 +1.1 +0.8 –64N 8 58.5 +1.1 +0.4 –55N 7 3419 ψ1 Aqr 4.2 DD +76 7 44.6 +0.4 +4.0 29N 8 8.8 –1.9 +8.4 10N 7 3419 ψ1 Aqr 4.2 RB +77 8 31.8 +3.1 –2.1 –38N 8 34.0 +5.7 –5.6 –23N 7 3425 ψ2 Aqr 4.4 DD +77 8 36.4 +2.2 –0.1 65S 8 47.0 +2.3 +0.5 72S 7 3425 ψ2 Aqr 4.4 RB +77 9 49.8 +0.9 +2.4 –54S 10 5.3 +1.0 +2.5 –58S 11 354 ξ Ari 5.5 DD +99 13 56.2 +1.2 +1.9 76N 14 10.8 +1.2 +2.2 72N 13 593 HIP 18735 5.9 RD –99 12 39.7 +1.5 +0.3 61S 12 49.0 +1.8 +0.6 64S 21 1701 ξ Vir 4.8 RD –29 17 43.0 +0.4 –2.9 29N 29 2725 28 Sgr 5.4 DD +9 9 13.8 –0.5 +2.1 51N 9 21.0 –0.7 +2.2 44NDec. 7 192 89 Psc 5.1 DD +78 10 34.8 +1.0 +2.1 59N 10 49.4 +1.0 +2.3 56N 11 700 HU Tau 5.9 DD +99 13 15.0 +1.6 +1.2 70N 13 28.8 +1.7 +1.7 65N 18 1651 ι Leo 3.9 RD –57 13 8.0 +0.7 –3.6 24N 22 2133 ξ Lib 5.5 RD –15 14 57.1 –0.3 –1.6 78N 14 48.2 –0.3 –1.7 70N

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42 Grazing Lunar Occultations BAA Handbook 2019

Lunar Occultations GRAZING LUNAR OCCULTATIONSThe map shows the tracks of stars to magnitude 8.0 which will graze the Moon’s limb and where the Moon is less than 90 percent sunlit, has an altitude of more than 5°.The track commences in the West, and the Time (UT) is near the centre of the region. Tracks marked on the map as `A´ indicate the star is at a low altitude. Tracks marked with a `B´ indicate the bright limb is close. Small or negative cusp angles indicate the graze occurs at the terminator. The track is terminated if the altitude (A) is low or when the sky (S) is bright.The Altitude (Alt) column is the approximate elevation of the Moon, as a guide to observability.

Accuracy: Recording events to a UT accuracy of 0.2s or better are desirable. Observers using video or planetary webcams, with UT time stamps, are invited to contact the Lunar Section for assistance with light curve analysis and reporting of times.Visual Observers: Individuals and teams should continue to send timings to the Lunar Section.

General circumstances for the events can be judged from personal planetarium software. More details of grazes may be computed using software for non–commercial use from:

http://www.lunar-occultations.com/iota/occult4.htm http://www.doa-site.nl/

Observers positioned on or very near the tracks may see the star disappear and reappear several times at the edge of features on the Moon’s limb. Observations continue to be valuable in the study and refinement of the shape and motion of the Moon, and in the detection of double or multiple stars, particularly during grazes. Potential observers are encouraged to contact Tim Haymes at [email protected] for additional information. A brief notification of success or failure of the observing attempt would be appreciated.

Key to the Map

2019 Star N or S Cusp name ZC* Time† V Sunlit‡ limit angle† sp alt. MM DD h m % °1 SAO158927 Jan. 1 5 30 7.8 -21 S 5.2 A0 122 SAO158942 Jan. 1 6 10 7.7 -21 S 5.6 K0 15 3 ξ Oph 2498 Jan. 31 6 48 4.4 -18 S 8.3 F2 8 4 55 Tau 636 Feb. 13 21 28 7.0 60+ S 2.7 F7 42 5 SAO 184922 2446 Feb. 27 3 39 7.4 -42 S 10.7 B7 6 6 SAO 160052 2401 Mar. 26 3 23 5.5 -70 S 10.6 F3 13 7 SAO 77547 Apr. 10 23 29 7.1 29+ S 0.9 K0 11 8 SAO 74806 May 8 21 57 7.6 16+ S 1.5 A0 15 9 SAO 74910 May 9 22 4 7.2 26+ N 0.5 G5 24 10 SAO 79131 1086 Jun. 5 21 18 6.4 7+ S 2.0 G9 11 11 δ Gem 1110 Aug. 27 4 15 3.5 -14 N 10.4 F0 27 12 SAO 78742 Sep. 22 23 47 7.0 -39 N 10.1 K0 9 13 SAO 79629 Oct. 21 5 32 7.1 -53 N 4.3 F5 58 14 SAO 98684 1421 Oct. 23 3 56 8.0 -31 N 7.0 K0 33 15 SAO 99210 1553 Oct. 24 4 43 7.8 -21 N 5.9 A0 26 16 η Gem 946 Nov. 15 22 3 3.5 -88 N 13.0 M3 30 17 SAO 98468 1377 Nov. 19 0 42 7.0 -59 N 7.6 A3 24 18 SAO 119227 Nov. 22 3 14 7.5 -24 N 3.3 K0 11

* Numbers taken from the Robertson Zodiacal Catalog or the Extended Zodiacal Catalog d = double, m = multiple, u = unconfirmed.† Precise times and cusp angles are dependent on location‡ a negative number indicates a waning Moonsp star spectrum classification alt. is dependent on location and is provided as a guide

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BAA Handbook 2019 Grazing Lunar Occultations 43

Lunar Occultations GRAZING LUNAR OCCULTATIONS

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44 Mars BAA Handbook 2019

MARS

Conjunction: Sep. 2

2019 RA Dec. V Diam P Q Ph. DE DS LS h m ° ' " ° ° ° ° °

Jan. –3 23 50.5 –1 27 0.4 7.6 335 67 0.871 –26.3 –17.8 314.17 0 14.9 +1 26 0.6 7.1 331 67 0.877 –26.0 –15.9 319.8

17 0 39.4 +4 17 0.7 6.7 328 67 0.883 –25.4 –14.0 325.427 1 4.2 +7 04 0.8 6.3 326 67 0.890 –24.4 –11.9 331.0

Feb. 6 1 29.4 +9 45 0.9 6.0 324 68 0.897 –23.0 –9.8 336.4

16 1 54.9 +12 18 1.1 5.7 322 69 0.905 –21.3 –7.7 341.826 2 20.9 +14 42 1.2 5.4 321 71 0.912 –19.2 –5.5 347.0

Mar. 8 2 47.3 +16 53 1.3 5.1 321 72 0.920 –17.0 –3.3 352.218 3 14.1 +18 50 1.3 4.9 322 74 0.927 –14.5 –1.2 357.328 3 41.5 +20 33 1.4 4.7 322 76 0.934 –11.9 1.0 2.3

Apr. 7 4 9.2 +21 58 1.5 4.5 324 78 0.942 –9.1 3.0 7.217 4 37.3 +23 06 1.6 4.4 326 81 0.948 –6.3 5.1 12.027 5 5.6 +23 55 1.6 4.2 328 83 0.955 –3.4 7.1 16.8

May 7 5 34.0 +24 24 1.7 4.1 331 86 0.961 –0.5 9.0 21.517 6 2.5 +24 34 1.7 4.0 334 89 0.967 2.3 10.8 26.2

27 6 30.8 +24 24 1.7 3.9 337 91 0.973 5.2 12.6 30.8Jun. 6 6 58.8 +23 55 1.8 3.8 341 94 0.978 7.9 14.3 35.3

16 7 26.5 +23 08 1.8 3.7 344 96 0.982 10.6 15.8 39.926 7 53.8 +22 04 1.8 3.7 348 98 0.986 13.1 17.3 44.3

Jul. 6 8 20.5 +20 44 1.8 3.6 352 100 0.990 15.5 18.7 48.8

16 8 46.7 +19 09 1.8 3.6 356 101 0.993 17.7 19.9 53.226 9 12.3 +17 22 1.8 3.5 0 102 0.996 19.7 21.1 57.6

Aug. 5 9 37.5 +15 23 1.8 3.5 4 102 0.998 21.4 22.1 62.015 10 2.1 +13 15 1.8 3.5 8 100 0.999 22.9 23.0 66.425 10 26.4 +10 57 1.8 3.5 12 90 1.000 24.1 23.7 70.7

Sep. 4 10 50.3 +8 34 1.7 3.5 16 358 1.000 25.0 24.3 75.114 11 14.0 +6 04 1.8 3.5 20 308 1.000 25.5 24.7 79.524 11 37.6 +3 31 1.8 3.5 23 301 0.999 25.7 25.0 83.8

Oct. 4 12 1.1 +0 56 1.8 3.6 27 299 0.997 25.6 25.2 88.214 12 24.7 –1 40 1.8 3.6 30 297 0.995 25.0 25.2 92.6

24 12 48.5 –4 15 1.8 3.6 32 296 0.992 24.2 25.0 97.1Nov. 3 13 12.5 –6 48 1.8 3.7 35 294 0.988 23.0 24.6 101.6

13 13 37.0 –9 17 1.8 3.8 36 293 0.984 21.5 24.1 106.123 14 1.9 –11 40 1.7 3.8 38 291 0.979 19.7 23.5 110.6

Dec. 3 14 27.4 –13 55 1.7 3.9 38 290 0.974 17.7 22.7 115.2

13 14 53.5 –16 01 1.7 4.0 39 288 0.968 15.4 21.7 119.823 15 20.2 –17 55 1.6 4.2 38 285 0.962 12.9 20.5 124.633 15 47.7 –19 36 1.6 4.3 37 283 0.955 10.3 19.2 129.3

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BAA Handbook 2019 Mars 45

LONGITUDE OF THE CENTRAL MERIDIAN OF MARS

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.° ° ° ° ° ° ° ° ° ° ° °

1 10.8 65.0 149.9 207.2 275.6 334.9 43.6 101.5 158.2 223.8 279.8 346.52 1.0 55.1 140.1 197.5 265.9 325.2 33.8 91.7 148.4 214.0 270.0 336.73 351.1 45.3 130.3 187.7 256.2 315.5 24.1 82.0 138.6 204.2 260.2 327.04 341.2 35.4 120.5 178.0 246.5 305.8 14.4 72.2 128.8 194.4 250.4 317.25 331.3 25.6 110.7 168.3 236.8 296.1 4.7 62.4 118.9 184.5 240.6 307.56 321.5 15.7 101.0 158.5 227.1 286.4 354.9 52.7 109.1 174.7 230.8 297.77 311.6 5.9 91.2 148.8 217.4 276.7 345.2 42.9 99.3 164.9 221.0 288.08 301.7 356.0 81.4 139.1 207.7 267.0 335.5 33.1 89.5 155.1 211.2 278.29 291.8 346.2 71.6 129.4 198.0 257.3 325.7 23.3 79.7 145.3 201.4 268.510 282.0 336.4 61.8 119.6 188.3 247.6 316.0 13.6 69.9 135.5 191.7 258.711 272.1 326.5 52.1 109.9 178.6 237.9 306.3 3.8 60.1 125.7 181.9 249.012 262.2 316.7 42.3 100.2 168.9 228.1 296.5 354.0 50.3 115.8 172.1 239.313 252.3 306.9 32.5 90.5 159.2 218.4 286.8 344.2 40.5 106.0 162.3 229.514 242.5 297.1 22.7 80.7 149.5 208.7 277.0 334.4 30.7 96.2 152.5 219.815 232.6 287.2 13.0 71.0 139.8 199.0 267.3 324.7 20.8 86.4 142.7 210.016 222.7 277.4 3.2 61.3 130.1 189.3 257.6 314.9 11.0 76.6 133.0 200.317 212.9 267.6 353.4 51.6 120.4 179.6 247.8 305.1 1.2 66.8 123.2 190.618 203.0 257.8 343.7 41.9 110.7 169.9 238.1 295.3 351.4 57.0 113.4 180.819 193.1 248.0 333.9 32.1 101.0 160.2 228.3 285.5 341.6 47.2 103.7 171.120 183.3 238.1 324.2 22.4 91.3 150.5 218.6 275.7 331.8 37.4 93.9 161.421 173.4 228.3 314.4 12.7 81.6 140.7 208.8 265.9 322.0 27.6 84.1 151.622 163.5 218.5 304.7 3.0 71.9 131.0 199.1 256.1 312.1 17.8 74.3 141.923 153.7 208.7 294.9 353.3 62.2 121.3 189.3 246.4 302.3 8.0 64.6 132.224 143.8 198.9 285.2 343.6 52.5 111.6 179.6 236.6 292.5 358.1 54.8 122.525 133.9 189.1 275.4 333.9 42.8 101.9 169.8 226.8 282.7 348.3 45.0 112.726 124.1 179.3 265.7 324.2 33.1 92.2 160.1 217.0 272.9 338.5 35.3 103.027 114.2 169.5 255.9 314.5 23.4 82.4 150.3 207.2 263.1 328.7 25.5 93.328 104.4 159.7 246.2 304.8 13.7 72.7 140.6 197.4 253.3 318.9 15.8 83.629 94.5 236.4 295.0 4.0 63.0 130.8 187.6 243.4 309.1 6.0 73.830 84.7 226.7 285.3 354.3 53.3 121.0 177.8 233.6 299.3 356.2 64.131 74.8 216.9 344.6 111.3 168.0 289.6 54.4

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h ° h ° m ° m ° m °

1 14.62 7 102.34 10 2.44 1 0.24 6 1.46 2 29.24 8 116.96 20 4.87 2 0.49 7 1.71 3 43.86 9 131.58 30 7.31 3 0.73 8 1.95 4 58.48 10 146.21 40 9.75 4 0.97 9 2.19 5 73.10 11 160.83 50 12.18 5 1.22 10 2.44 6 87.72 12 175.45 60 14.62

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46 Asteroids BAA Handbook 2019

ASTEROIDS

ORBITAL ELEMENTS

Observers with binoculars or small telescopes may find these data useful in locating some of the brighter asteroids.

The data below, for asteroids brighter than magnitude 9.3 at opposition, have been extracted from the Minor Planet Center’s Minor Planet and Comet Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox of the elements J2000Epoch of the elements JD 2458200.5, 2018 Mar. 23.0 TT

No. Name a e i Node Peri. M au º º º º 2 Pallas 2.773 0.231 34.837 173.084 310.006 334.323 3 Juno 2.669 0.257 12.990 169.859 248.182 304.480 4 Vesta 2.362 0.089 7.141 103.815 150.761 347.186 6 Hebe 2.425 0.203 14.737 138.648 239.849 341.782 9 Metis 2.387 0.123 5.577 68.909 6.322 169.985 15 Eunomia 2.646 0.186 11.733 293.043 98.004 192.255 18 Melpomene 2.295 0.219 10.132 150.465 227.840 154.038 29 Amphitrite 2.556 0.072 6.082 356.374 63.036 187.970 39 Laetitia 2.771 0.112 10.370 157.072 208.482 216.694 433 Eros 1.458 0.223 10.828 304.317 178.802 183.282 532 Herculina 2.773 0.176 16.313 107.534 76.214 258.937

WEBSITE

More information on asteroids and dwarf planets can be found on the website of the Asteroids and Remote Planets Section at:

http://www.britastro.org/asteroids/

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BAA Handbook 2019 Asteroids 47

ASTEROID EPHEMERIDESThe geocentric data below, for asteroids listed on p.46, have been extracted from the Minor Planet Center Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox of the elements J2000Epoch of the elements JD 2458200.5, 2018 Mar. 23.0 TT

2 Pallas

2019 RA Dec. Δ r Elong. V h m s º ' " au au º Jan. 1 13 22 20.8 –5 59 53 2.295 2.314 78.7 9.0 11 13 35 20.7 –5 10 57 2.183 2.334 86.2 8.9 21 13 46 48.1 –3 58 23 2.070 2.355 94.1 8.8 31 13 56 26.2 –2 19 50 1.960 2.377 102.5 8.6Feb. 10 14 03 54.9 –0 13 26 1.857 2.399 111.3 8.5 20 14 08 55.9 +2 20 53 1.765 2.421 120.5 8.4Mar. 2 14 11 14.7 +5 20 32 1.688 2.444 129.8 8.2 12 14 10 42.8 +8 39 14 1.631 2.467 138.9 8.0 22 14 07 27.5 +12 06 01 1.598 2.491 146.7 7.9Apr. 1 14 01 53.2 +15 26 41 1.591 2.515 151.6 7.9 11 13 54 43.2 +18 26 03 1.611 2.539 151.9 7.9 21 13 46 57.7 +20 51 39 1.658 2.563 147.5 8.0May 1 13 39 37.9 +22 36 51 1.730 2.588 140.5 8.2 11 13 33 37.1 +23 40 40 1.822 2.612 132.5 8.5 21 13 29 33.0 +24 06 42 1.930 2.637 124.3 8.7 31 13 27 42.2 +24 01 06 2.051 2.661 116.4 8.9Jun. 10 13 28 08.0 +23 30 09 2.181 2.685 108.8 9.1 20 13 30 43.4 +22 39 58 2.316 2.710 101.6 9.2 30 13 35 15.0 +21 35 37 2.455 2.734 94.7 9.4Jul. 10 13 41 29.7 +20 21 04 2.595 2.758 88.2 9.5 20 13 49 13.2 +18 59 44 2.734 2.782 82.0 9.6 30 13 58 12.7 +17 34 09 2.870 2.805 76.1 9.7Aug. 9 14 08 18.3 +16 06 24 3.003 2.829 70.4 9.8 19 14 19 20.3 +14 38 20 3.130 2.852 64.9 9.9

3 Juno2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 3 33 35.2 –2 28 21 1.243 1.998 127.2 8.2 11 3 36 32.9 –0 58 41 1.332 2.006 119.3 8.4 21 3 42 31.0 +0 43 58 1.431 2.016 111.8 8.6 31 3 51 09.1 +2 33 10 1.537 2.028 104.9 8.8Feb. 10 4 02 07.6 +4 24 00 1.650 2.041 98.3 9.0 20 4 15 06.0 +6 12 25 1.767 2.056 92.1 9.2Mar. 2 4 29 44.6 +7 55 16 1.886 2.072 86.2 9.3 12 4 45 47.8 +9 30 16 2.008 2.090 80.6 9.4 22 5 03 00.8 +10 55 29 2.131 2.109 75.2 9.6Apr. 1 5 21 09.7 +12 09 34 2.253 2.130 70.0 9.7 11 5 40 04.0 +13 11 36 2.375 2.151 64.9 9.8 21 5 59 32.4 +14 00 54 2.495 2.174 60.0 9.9

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48 Asteroids BAA Handbook 2019

4 Vesta2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jun. 30 2 30 04.2 +8 11 56 2.803 2.459 60.1 8.2Jul. 10 2 44 16.1 +9 05 23 2.701 2.467 65.9 8.2 20 2 57 38.8 +9 49 54 2.592 2.475 72.0 8.1 30 3 10 02.1 +10 25 11 2.479 2.483 78.4 8.0Aug. 9 3 21 11.8 +10 50 57 2.362 2.491 85.2 8.0 19 3 30 53.1 +11 07 08 2.243 2.498 92.3 7.8 29 3 38 48.2 +11 13 47 2.124 2.505 99.9 7.7Sep. 8 3 44 36.6 +11 11 01 2.008 2.512 108.1 7.6 18 3 47 58.9 +10 59 25 1.898 2.518 116.9 7.4 28 3 48 36.8 +10 39 44 1.796 2.524 126.4 7.2 Oct. 8 3 46 17.8 +10 13 16 1.708 2.530 136.7 7.1 18 3 41 04.7 +9 42 15 1.638 2.535 147.5 6.9 28 3 33 17.3 +9 09 36 1.589 2.540 158.5 6.7Nov. 7 3 23 40.3 +8 39 17 1.566 2.545 168.2 6.5 17 3 13 19.8 +8 15 47 1.571 2.549 169.0 6.5 27 3 03 28.1 +8 02 59 1.605 2.553 159.6 6.7Dec. 7 2 55 12.4 +8 03 42 1.664 2.556 148.5 6.9 17 2 49 19.8 +8 18 56 1.747 2.560 137.4 7.1 27 2 46 13.1 +8 48 02 1.848 2.562 126.9 7.3

6 Hebe2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 6 18 58.4 +5 53 49 1.274 2.230 161.8 8.5 11 6 09 23.2 +7 23 39 1.317 2.252 156.2 8.7 21 6 01 58.1 +9 03 40 1.385 2.275 147.1 8.9 31 5 57 29.2 +10 46 30 1.475 2.298 137.3 9.2Feb. 10 5 56 14.8 +12 26 35 1.583 2.321 127.6 9.4 20 5 58 12.5 +13 59 59 1.707 2.343 118.3 9.7Mar. 2 6 03 03.9 +15 24 23 1.841 2.366 109.7 9.9 12 6 10 27.8 +16 38 28 1.982 2.389 101.6 10.1 22 6 20 01.1 +17 41 33 2.129 2.412 94.0 10.3Apr. 1 6 31 20.5 +18 33 20 2.277 2.434 86.7 10.4

ASTEROID EPHEMERIDES

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BAA Handbook 2019 Asteroids 49

9 Metis2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Aug. 9 2 14 37.7 +7 02 25 1.804 2.246 102.0 10.5 19 2 22 49.6 +7 31 22 1.682 2.233 109.5 10.3 29 2 28 48.7 +7 48 45 1.565 2.221 117.5 10.1Sep. 8 2 32 08.8 +7 54 07 1.457 2.209 126.3 9.8 18 2 32 29.4 +7 47 52 1.361 2.197 135.8 9.6 28 2 29 37.2 +7 31 01 1.281 2.186 146.2 9.3Oct. 8 2 23 38.2 +7 06 01 1.219 2.175 157.2 9.0 18 2 15 09.1 +6 37 13 1.180 2.165 168.3 8.7 28 2 05 14.0 +6 10 17 1.165 2.155 173.3 8.6Nov. 7 1 55 20.2 +5 51 45 1.176 2.146 163.9 8.8 17 1 46 55.9 +5 47 14 1.211 2.137 152.4 9.1 27 1 41 05.6 +5 59 50 1.268 2.130 141.3 9.3Dec. 7 1 38 27.6 +6 30 32 1.343 2.122 130.8 9.5 17 1 39 10.1 +7 18 08 1.432 2.116 121.1 9.8 27 1 43 03.0 +8 20 13 1.531 2.110 112.2 10.0

15 Eunomia2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Apr. 21 21 05 27.0 –16 50 40 2.679 2.633 76.5 10.5May 1 21 16 42.2 –15 31 05 2.531 2.613 83.3 10.4 11 21 26 36.3 –14 11 25 2.383 2.593 90.3 10.2 21 21 34 57.7 –12 52 53 2.236 2.573 97.6 10.1 31 21 41 33.3 –11 36 47 2.091 2.553 105.2 9.9 Jun. 10 21 46 06.3 –10 24 39 1.953 2.533 113.3 9.7 20 21 48 21.6 –9 18 03 1.822 2.513 122.0 9.5 30 21 48 04.5 –8 18 41 1.703 2.493 131.1 9.3Jul. 10 21 45 05.0 –7 28 21 1.599 2.473 140.9 9.0 20 21 39 27.2 –6 48 30 1.514 2.453 151.2 8.8 30 21 31 31.1 –6 20 03 1.450 2.434 161.5 8.5Aug. 9 21 21 59.7 –6 03 05 1.410 2.415 169.8 8.3 19 21 11 58.3 –5 56 08 1.396 2.396 168.1 8.3 29 21 02 38.6 –5 56 40 1.408 2.377 158.6 8.4Sep. 8 20 55 08.8 –6 01 18 1.443 2.359 148.0 8.6 18 20 50 18.1 –6 06 16 1.499 2.341 137.5 8.8 28 20 48 29.8 –6 08 23 1.572 2.324 127.7 9.0Oct. 8 20 49 49.7 –6 04 55 1.657 2.307 118.4 9.2 18 20 54 07.0 –5 53 46 1.752 2.291 109.8 9.3 28 21 01 03.3 –5 33 37 1.853 2.275 101.8 9.5 Nov. 7 21 10 19.4 –5 03 27 1.958 2.261 94.4 9.6 17 21 21 33.5 –4 22 43 2.063 2.247 87.4 9.7 27 21 34 26.8 –3 31 19 2.168 2.233 80.8 9.8Dec. 7 21 48 43.4 –2 29 15 2.271 2.221 74.5 9.8 17 22 04 08.2 –1 16 58 2.371 2.209 68.5 9.9

ASTEROID EPHEMERIDES

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50 Asteroids BAA Handbook 2019

ASTEROID EPHEMERIDES18 Melpomene

2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° May 11 19 05 13.8 –9 29 39 1.695 2.392 122.3 10.5 21 19 05 38.3 –8 55 21 1.576 2.369 131.3 10.2 31 19 03 08.2 –8 30 51 1.471 2.345 140.7 10.0Jun. 10 18 57 43.2 –8 19 49 1.383 2.321 150.4 9.7 20 18 49 45.7 –8 25 21 1.316 2.296 159.6 9.4 30 18 40 00.4 –8 49 04 1.273 2.271 165.5 9.2Jul. 10 18 29 35.7 –9 30 44 1.253 2.246 163.2 9.2 20 18 19 54.1 –10 27 42 1.259 2.221 154.9 9.4 30 18 12 09.0 –11 35 41 1.286 2.196 144.9 9.5Aug. 9 18 07 16.8 –12 50 04 1.332 2.170 134.9 9.7 19 18 05 48.1 –14 06 18 1.394 2.145 125.4 9.8 29 18 07 48.8 –15 20 43 1.467 2.120 116.5 10.0Sep. 8 18 13 13.0 –16 30 25 1.548 2.095 108.2 10.1 18 18 21 43.8 –17 32 55 1.634 2.071 100.6 10.3 28 18 33 00.9 –18 26 18 1.723 2.046 93.5 10.4

29 Amphitrite2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jul. 20 1 18 35.7 +8 22 48 2.144 2.459 95.5 10.5 30 1 25 59.4 +9 28 47 2.016 2.452 102.9 10.4Aug. 9 1 31 26.3 +10 25 28 1.893 2.445 110.9 10.2 19 1 34 37.4 +11 11 41 1.776 2.439 119.5 10.0 29 1 35 13.7 +11 46 02 1.669 2.432 128.7 9.8 Sep. 8 1 33 01.5 +12 06 59 1.576 2.426 138.8 9.6 18 1 28 02.7 +12 13 34 1.500 2.420 149.5 9.3 28 1 20 36.7 +12 05 39 1.445 2.415 160.9 9.1Oct. 8 1 11 29.1 +11 44 51 1.415 2.409 172.2 8.8 18 1 01 48.3 +11 15 22 1.412 2.404 173.0 8.8 28 0 52 48.5 +10 43 02 1.436 2.399 161.7 9.0Nov. 7 0 45 38.1 +10 14 29 1.484 2.395 150.1 9.3 17 0 41 03.1 +9 55 28 1.555 2.391 139.0 9.5 27 0 39 23.5 +9 49 32 1.644 2.387 128.6 9.7Dec. 7 0 40 41.8 +9 58 24 1.747 2.384 118.8 9.9 17 0 44 45.6 +10 22 04 1.860 2.380 109.8 10.1 27 0 51 16.7 +10 59 16 1.979 2.378 101.4 10.3

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BAA Handbook 2019 Asteroids 51

39 Laetitia2019 RA Dec. ∆ r Elong. V h m s ° ' " au au °Jun. 20 21 57 57.8 –5 31 57 1.937 2.579 118.3 10.5 30 21 59 48.4 –5 33 09 1.822 2.569 127.3 10.3Jul. 10 21 59 17.2 –5 52 36 1.720 2.560 137.0 10.1 20 21 56 25.2 –6 31 27 1.636 2.551 147.4 9.8 30 21 51 24.6 –7 29 09 1.571 2.542 158.3 9.6 Aug. 9 21 44 45.2 –8 42 42 1.530 2.534 169.4 9.3 19 21 37 16.8 –10 06 17 1.516 2.526 175.5 9.1 29 21 29 57.2 –11 32 32 1.527 2.518 165.7 9.4Sep. 8 21 23 47.3 –12 53 56 1.565 2.511 154.4 9.6 18 21 19 36.8 –14 04 16 1.625 2.504 143.4 9.8 28 21 17 55.0 –14 59 47 1.705 2.498 132.9 10.1Oct. 8 21 18 55.7 –15 38 36 1.801 2.492 123.1 10.2 18 21 22 35.5 –16 00 30 1.909 2.487 114.0 10.4

433 Eros2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 4 13 01.2 +50 58 47 0.218 1.158 139.7 9.1 11 4 24 58.8 +43 05 54 0.209 1.145 136.8 9.1 21 4 44 20.3 +34 15 05 0.210 1.137 132.6 9.2 31 5 08 13.8 +25 28 23 0.220 1.133 127.7 9.3Feb. 10 5 34 43.8 +17 37 12 0.239 1.135 123.1 9.6 20 6 02 37.9 +11 07 04 0.266 1.142 119.1 9.9Mar. 2 6 31 03.2 +5 58 46 0.299 1.154 115.9 10.2 12 6 59 43.8 +2 01 10 0.338 1.170 113.4 10.5

532 Herculina2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 9 53 25.6 +21 42 14 1.640 2.447 136.3 9.6 11 9 51 56.8 +23 29 44 1.550 2.432 146.7 9.3 21 9 47 35.5 +25 31 21 1.481 2.418 157.0 9.1 31 9 40 46.1 +27 37 28 1.439 2.404 164.9 8.9Feb. 10 9 32 19.5 +29 35 54 1.424 2.391 165.0 8.9 20 9 23 34.3 +31 14 57 1.436 2.378 157.1 9.0Mar. 2 9 15 53.7 +32 27 08 1.473 2.366 146.9 9.2 12 9 10 29.5 +33 09 53 1.531 2.355 136.7 9.4 22 9 08 08.1 +33 24 53 1.607 2.344 126.9 9.6Apr. 1 9 09 03.4 +33 16 00 1.695 2.334 117.8 9.7 11 9 13 09.7 +32 47 07 1.792 2.326 109.4 9.9 21 9 20 07.4 +32 01 42 1.896 2.317 101.6 10.0May 1 9 29 29.5 +31 02 23 2.002 2.310 94.5 10.2 11 9 40 51.2 +29 50 59 2.109 2.304 87.8 10.3 21 9 53 48.4 +28 28 58 2.216 2.299 81.6 10.4

ASTEROID EPHEMERIDES

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52 Asteroids BAA Handbook 2019

ASTEROID OCCULTATIONS

OCCULTATIONS OF STARS BY ASTEROIDS AND DWARF PLANETSFavourable events predicted by Edwin Goffin: http://bedekkingen.vvs.be/predictions/Asteroids2019/

Four predictions are highlighted below. These represent reasonably good opportunities for UK observers (see page 53 for corresponding Chart). Max Star Asteroid Asteroid Star Date UT ΔM Duration Magnitude Diameter hh:mm s km90 Antiope* TYC 1868-281-1 Jan. 04 23:20 2.8 8.4 10.8 121489 Comacina TYC 5157-1423-1 Jul. 26 01:15 3.2 10.5 11.0 139511 Davida** TYC 1330-534-1 Sep. 04 04:19 1.5 8.6 10.5 2832064 Thomsen TYC 6298-2398-1 Sep. 23 20:33 5.1 11.4 9.8 151 * One moon {S/2000(90)1}, diameter 84 km, period 0.69 days, distance 171 km - The prediction is for the overall longer dimension of the binary system.** TwilightKey for the table above: ΔM The change in V magnitude. Max Duration Duration of the occultation for an observer at the centre of the shadow path Star Magnitude Visual magnitude of the star

Featured TNO: (Southern Hemisphere)28978 Ixion occults UCAC5 304−133829 on 2019 June 14:17 UT. The 800 km wide path will cross South Africa and S/SE Australia. UCAC5 304−133829 is of reasonable brightness at Vmag 12.8 with total extinction during the occulted phase. Moonlight should not interfere and the maximum duration is expected to be about 32 seconds. Details here: http://bedekkingen.vvs.be/predictions/asteroids2019/PDF/B19_06002.pdf

Regional predictionsPredictions for region 3 and overlapping areas chosen criteria:Star Mag 11.2 and brighter, duration >3s, magnitude drop >1.3

TNO Global predictionsNamed objects are listed for all regions.

Major planetsAll major planet events are listed.

Prediction uncertaintiesErrors are reduced now that the Gaia DR2 data is released. The main uncertainty is in the ephemeris of the object or where there is some undetected stellar multiplicity. Observer should continue to monitor outside the path to detect possible anomalies or satellites. Mobile observers could consider setting up in the track.Event durationThe duration of an occultation depends on where the observer is positioned within the track. Negative and positive results are published on EURASTER.NET website : http://www.euraster.net/results/index.html – where there is a link to the BEST results.

Recording and reporting an observationObservations should be timed with a UT accuracy of typically 0.1 to 0.3 sec and reported to the Asteroids and Remote Planets Section and the PLANOCCULT list server. Negative observations (no occultation) should also be reported. European observers are strongly encouraged to subscribe to the PLANOCCULT mailing list for last-minute updates and observation reports : - visit : http://vps.vvs.be/mailman/listinfo/planoccult and follow the instructions to use the list server.

For more up-to-date information on predictions, finder charts and occultation news, consult the following home pages : http://www.iota-es.de/ - International Occultation Timing Association http://www.lesia.obspm.fr/perso/bruno-sicardy/ - Bruno Sicardy http://astro.kretlow.de - Database maintained by Mike Kretlow http://asteroidoccultations.com/2019-BestEvents.htm - Steve Preston

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BAA Handbook 2019 Asteroids 53

ASTEROID OCCULTATIONS

TNO HIGHLIGHT28978 Ixion & UCAC5 304−133829

2019 jun 14 17h38.4m U.T.

Planet: Star: Source cat. UCAC5

V. mag. = 19.53 Diam. = 794.3 km = 0.03" α = 17h48m47.725s δ = −29°18'56.46"

µ = 3.23"/h π = 0.23" Ref. = EG2017 Vmag = 12.77 Bmag = 13.18

∆m = 6.8 Max. dur. = 31.9s Sun : 172° Moon : 38° , 92%

a = 39.71, e = 0.24

Vis.

magn.

scale

3

4

5

6

7

8

9

10

11

12

17h52 17h51 17h50 17h49 17h48 17h47 17h46 17h45

−29°40

−29°30

−29°20

−29°10

−29°00

−28°50

Right ascension (2000.0)

Declin

ation (

2000.0

)

17h34m00s − 17h43m00s; int. 1m

B19_06002.ps: 2018-03-09 09:27:02 22 Edwin Goffin, Hoboken, Belgium

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54 Asteroids BAA Handbook 2019

Jan. 4 3 8.2 271 Penthesilea 0.05 PPMX 5017717 11.09 5.3 2.8 1, 3 4 3 13.2 479 Caprera 0.08 TYC 0758-01699-1 11.09 7.8 1.6 1, 3 4 23 20.1 90 Antiope 0.07 TYC 1868-00281-1 10.83 8.7 2.6 1, 3 17 18 22.4 25 Phocaea 0.05 TYC 4791-00936-1 11.13 5.9 1.6 3,5,7 25 20 10.8 46 Hestia 0.09 TYC 0634-00468-1 10.27 7.1 2.8 3 28 19 2.8 667 Denise 0.07 TYC 4792-01753-1 10.77 6.3 2.4 3Feb. 2 3 16.8 145 Adeona 0.08 TYC 5618-01134-1 10.37 6.3 3.2 3 2 5 3.3 260 Huberta 0.04 HIP 78503 9.71 4.0 5.8 3,7 12 20 15.3 571 Dulcinea 0.04 UCAC5 532-047602 9.50 3.5 5.4 3 19 2 42.5 186 Celuta 0.04 TYC 2501-00455-1 10.47 3.9 2.5 1,3 21 21 31.9 1977 Shura 0.04 TYC 0833-00142-1 10.72 4.5 4.6 3,5 22 1 1.8 623 Chimaera 0.05 TYC 0239-01406-1 9.75 4.0 4.2 1,3Mar. 7 4 57.5 108 Hecuba 0.04 TYC 0841-00363-1 11.11 5.4 1.7 3 8 3 31.7 788 Hohensteina 0.07 UCAC5 417-056707 10.62 15.7 2.4 3,5 28 20 23.6 663 Gerlinde 0.06 TYC 0155-02781-1 10.49 7.1 4.0 3Apr. 1 20 23.4 80 Sappho 0.05 TYC 1299-01931-1 9.90 3.2 3.1 3 7 3 31.2 155 Scylla 0.04 TYC 4973-00045-1 9.71 3.6 5.7 1,3May 22 0 31.1 914 Palisana 0.09 TYC 6282-00100-1 9.48 7.1 2.3 3,4 28 0 20.1 225 Henrietta 0.09 TYC 0355-00548-1 10.24 10.7 2.8 3Jun. 7 18 48.8 121 Hermione 0.10 UCAC5 401-055242 10.66 23.1 2.6 3,5 12 1 30.6 487 Venetia 0.04 UCAC5 440-055388 9.73 8.6 3.2 1,3 23 1 19.2 130 Elektra 0.12 TYC 5239-01435-1 10.99 21.2 1.4 3Jul. 26 0 18.5 489 Comacina 0.09 TYC 5157-01423-1 11.02 10.8 2.2 3 26 4 48.9 94 Aurora 0.10 TYC 1216-00604-1 10.48 9.9 2.8 3 29 19 18.7 234 Barbara 0.04 UCAC5 447-056858 11.07 3.9 2.0 3Aug. 16 3 39.2 759 Vinifera 0.06 TYC 0582-00408-1 9.95 5.0 3.3 3 17 0 12.5 709 Fringilla 0.04 TYC 2418-01109-1 9.50 3.0 5.3 3 17 23 59.2 759 Vinifera 0.06 UCAC5 488-134811 10.68 5.0 2.6 3 26 0 40.4 1015 Christa 0.06 UCAC5 426-001328 10.09 15.7 3.8 3,5 28 3 20.9 624 Hektor 0.04 TYC 5246-00764-1 10.16 7.8 4.5 1,3Sep. 7 23 48.3 888 Parysatis 0.04 HIP 4643 10.72 4.9 2.4 3 11 20 34.6 91 Aegina 0.06 TYC 6816-00286-1 10.63 7.5 3.7 3 18 19 26.1 200 Dynamene 0.07 UCAC5 314-167327 11.04 11.6 2.6 3 24 22 24.3 113 Amalthea 0.04 TYC 0040-00504-1 10.93 5.3 1.7 3Oct. 2 19 57.9 795 Fini 0.05 TYC 4672-00259-1 10.67 5.2 3.2 3,5 6 4 49.1 120 Lachesis 0.07 TYC 1943-00184-1 11.07 6.1 2.8 3 8 0 55.2 419 Aurelia 0.05 TYC 0816-00536-1 10.44 4.9 4.1 3 9 21 43.0 547 Praxedis 0.06 UCAC5 433-107716 10.93 6.8 2.8 3 10 22 16.4 578 Happelia 0.05 HIP 17043 7.27 9.3 6.5 3,5 14 2 41.5 1048 Feodosia 0.04 TYC 1875-00091-1 11.09 9.8 4.3 3 15 6 36.3 144 Vibilia 0.12 TYC 1896-01786-1 10.94 13.2 1.7 1,3 18 2 36.5 508 Princetonia 0.06 TYC 1949-01606-1 10.61 6.4 3.7 3 29 23 43.6 87 Sylvia 0.11 TYC 1932-00469-1 10.05 21.8 3.3 3,5Nov. 4 1 10.0 567 Eleutheria 0.05 UCAC5 591-039832 10.92 13.3 3.8 3,5 9 0 21.7 480 Hansa 0.04 TYC 0176-01146-1 10.38 4.9 2.6 3 27 20 56.5 445 Edna 0.07 TYC 2905-01262-1 11.16 7.1 2.4 3,5,7Dec. 3 0 54.5 154 Bertha 0.08 TYC 0885-00412-1 9.64 6.4 3.8 3, 5 5 20 21.1 1390 Abastumani 0.06 UCAC5 686-045133 11.09 7.9 3.7 3, 6 10 23 54.4 309 Fraternitas 0.04 TYC 1804-00682-1 9.19 4.8 5.2 3 12 1 39.4 87 Sylvia 0.13 TYC 1947-00290-1 10.98 29.0 2.0 1,3,5 19 2 49.0 329 Svea 0.07 UCAC5 439-039297 10.67 10.5 3.0 1,3 24 7 8.0 159 Aemilia 0.05 TYC 5555-00367-1 10.21 4.1 3.9 3 29 1 28.6 743 Eugenisis 0.04 TYC 0806-01299-1 10.44 5.8 3.6 3

ASTEROID OCCULTATIONSREGIONAL PREDICTIONS

Minor Planet Diam Max. Mag.Date Time No. Name (IRAS) Star ID V Dur. drop RoV2019 h m " sec.

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BAA Handbook 2019 Asteroids 55

Jan. 11 14 30.7 944 Hidalgo 0.03 UCAC5 850-010266 14.80 5.6 0.6 1,5Mar. 9 9 22.2 136472 Makemake 0.12 UCAC5 572-047492 14.59 181.6 2.6 1,2Mar. 13 8 35.8 10370 Hylonome 0.01 UCAC5 357-160286 14.80 6.1 7.3 2May 20 12 11.1 38628 Huya 0.02 UCAC5 420-063781 14.23 20.1 5.2 7Jun. 14 17 38.4 28978 Ixion 0.03 UCAC5 304-133829 12.77 31.9 6.8 4,8Jul. 8 9 7.7 38628 Huya 0.02 UCAC5 420-063419 12.51 26.5 7.0 8Jul. 15 0 41.6 10370 Hylonome 0.01 UCAC5 357-155269 14.06 4.6 7.8 2Jul. 17 12 44.1 134340 Pluto 0.10 UCAC5 340-173206 12.91 98.4 1.8 7Jul. 24 1 25.4 83982 Crantor 0.01 UCAC5 350-178947 14.44 3.3 7.2 2Aug. 8 21 42.0 10199 Chariklo 0.02 UCAC5 323-192195 15.00 12.3 3.8 2,4Sep. 5 14 57.5 134340 Pluto 0.10 UCAC5 339-167569 13.42 186.1 1.6 6,7Sep. 13 23 23.0 66652 Borasisi 0.01 UCAC5 435-113798 13.81 11.1 8.3 5Dec. 16 5 16.1 32532 Thereus 0.01 UCAC5 427-047196 13.51 5.7 6.8 2

MAJOR PLANET PREDICTIONS

ASTEROID OCCULTATIONSTNO GLOBAL PREDICTIONS

Minor Planet Diam Max. Mag.Date Time No. Name (IRAS) Star ID V Dur. drop RoV2019 h m " sec.

Planet Max. Date Time Name Diam Star ID V Dur. RoV2019 h m " sec.

Feb. 27 23 51 Mars 5.3 TYC 1215-01062-1 9.97 190 1Mar. 9 10 28 Mars 5.1 UCAC5 536-004707 9.86 183 7Apr. 10 11 55 Mars 4.5 HIP 20038 8.24 163 8Jun. 3 19 33 Jupiter 45.9 HIP 84543 9.40 8762 3,6,7,8Oct. 21 11 49 Jupiter 34.1 HIP 84936 8.75 4639 6,8Oct. 13 8 19 Neptune 2.3 UCAC5 418-145773 12.40 2531 1,8

Using the tablesIn the table of predictions : Time = UT of closest geocentric approach. Region of Visibility codes (RoV): 1 = North and Central America 2 = South America 3 = Europe, N. Africa and the Middle East 4 = South Africa 5 = Russia 6 = Pakistan, India, and SE Asia

7 = Japan, China and Taiwan 8 = Australia and New Zealand

Where diameters are not listed in the IRAS catalogue, an assumed value of A, the geometric albedo, has been used to calculate a value for the asteroid diameter. Predictions computed by Edwin Goffin. Track details are available from the Flemish Astronomical Association ftp site:

http://bedekkingen.vvs.be/predictions/asteroids2019/Occ19R03.pdf

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56 Asteroids BAA Handbook 2019

ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES

LIGHTCURVE OPPORTUNITIES

Based on an analysis of both numbered and unnumbered objects in the Minor Planet Center MPCORB database by Brian D. Warner.

Asteroids are listed which at opposition reach magnitude 14.5 or brighter, and for which the rotation period is very uncertain or unknown.Where a 'U' code is given as '1' or ‘1+’, the values given are based on fragmentary lightcurves and are likely to be incorrect.

Period/amplitude data are taken from the list maintained by Brian D. Warner, Alan W. Harris of the Space Science Institute and Petr Pravec of the Astronomical Institute, Ondrejov, Czech Republic, at:

http://www.minorplanet.info/lightcurvedatabase.html

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BAA Handbook 2019 Asteroids 57

Asteroid Opposition Amplitude Number Name Date V Δ Dec. U Period of Magnitude Variation m d au ° Code h

2162 Anhui 01 11.3 14.4 1.068 +20 1720 Niels** 01 17.0 14.3 1.020 +21 1 9.976 0.151397 Umtata 04 11.6 14.4 1.435 –3 1 30. 0.13722 Frieda 04 19.7 14.5 1.146 –8 0.04957 Camelia 05 08.8 14.0 2.057 –19 1+ 150. 0.30 1968 Mehltretter** 06 03.8 14.4 1.429 –22 3093 Bergholz 06 15.7 14.5 1.434 –29 5445 Williwaw 06 18.4 14.1 1.042 –22 2081 Sazava 06 28.4 14.0 1.046 –27 4420 Alandreev 07 20.8 13.6 0.810 –22 6649 Yokotatakao 07 22.7 14.5 0.889 –27 1354 Botha 08 03.1 14.3 1.510 –27 1+ 4 0.211066 Lobelia 08 17.9 13.8 0.964 –17 1032 Pafuri 08 21.0 14.1 1.888 –25 1 >24. 0.15-0.31686 De Sitter 08 29.2 14.4 1.713 –10 7365 Sejong 09 01.2 14.1 0.731 –8 2302 Florya 09 01.9 14.4 1.212 +3 1 >12. 0.052389 Dibaj 09 08.0 14.3 0.926 –3 848 Inna 09 09.0 14.4 1.605 –5 2580 Smilevskia 09 11.2 13.7 0.753 –7

2466 Golson 09 26.3 14.3 1.209 –2 795 Fini 09 30.7 14.0 2.008 –2 1+ 9.292 0.02-0.06162082 1998 HL1# 10 27.5* 12.3 0.043 +13 3171 Wangshouguan 11 02.1 14.5 1.744 +17 481394 2006 SF6# 11 11.8* 13.8 0.051 +16 2569 Madeline 11 11.7 13.5 1.232 +8 0.11429 Pemba 11 26.3 14.5 1.148 +25 1 >20. 0.31359 Prieska 12 01.7 14.2 1.933 +23 0.04-0.054700 Carusi 12 20.8 14.5 1.066 +26 2326 Tololo 12 21.9 14.3 1.528 +1 4421 Kayor 12 29.8 14.4 1.160 +24

* When brightest, **Low phase angle target, # Near-Earth asteroid

ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES

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58 Asteroids BAA Handbook 2019

ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIESOPPORTUNITIES AT LOW PHASE ANGLE AND AT OPPOSITION

Asteroids have been selected on the following criteria: V≤14.5, Phase Angle ≤0.15°

Asteroid Opposition Minimum Maximum Number Name Date Phase Angle V Dec. Period Lightcurve Amplitude m d ° ° h mag

638 Moira 01 05.4 0.09 13.9 +23 9.875 0.31 607 Jenny 01 06.8 0.06 13.8 +22 8.521 0.26 3266 Bernardus 01 11.2 0.12 14.2 +22 10.757 1.14 1720 Niels 01 17.1 0.14 14.3 +21 9.976 0.15 1269 Rollandia 02 01.8 0.04 13.6 +17 19.98 0.13 226 Weringia 02 04.2 0.02 14.2 +16 11.147 0.38 335 Roberta 02 15.0 0.13 12.5 +13 12.054 0.78 1614 Goldschmidt 03 02.4 0.15 14.3 +7 8.873 0.14 167 Urda 03 09.2 0.04 13.0 +5 13.07 0.39 50 Virginia 03 16.6 0.04 13.7 +2 14.315 0.20 337 Devosa 03 17.1 0.06 11.1 +1 4.653 0.75 904 Rockefellia 04 08.4 0.02 14.4 –7 6.826 0.18 229 Adelinda 04 09.8 0.11 14.2 –7 6.60 0.30 540 Rosamunde 04 13.4 0.07 12.4 –9 9.351 0.66 67 Asia 04 14.0 0.07 11.1 –9 15.853 0.26 551 Ortrud 05 03.9 0.11 13.9 –16 17.416 0.19 936 Kunigunde 05 19.8 0.08 14.2 –20 8.8 0.25 1968 Mehltretter 06 03.8 0.07 14.4 –22 517 Edith 06 22.7 0.07 14.2 –24 9.2747 0.18 1063 Aquilegia 06 28.3 0.07 13.7 –23 5.792 0.93 2524 Budovicium 07 10.2 0.03 14.3 –22 10.0819 0.17 158 Koronis 07 12.2 0.10 13.1 –22 14.218 0.43 440 Theodora 07 23.2 0.15 14.3 –20 4.828 0.72 1271 Isergina 07 29.7 0.05 14.4 –19 7.59932 0.36 180 Garumna 08 02.8 0.01 14.5 –18 23.866 0.6 1467 Mashona 08 20.4 0.11 12.4 –12 9.76 0.31 243 Ida 09 01.0 0.15 13.6 –8 4.634 0.86 135 Hertha 09 06.3 0.02 9.6 –7 8.403 0.30 443 Photographica 09 18.6 0.02 12.7 –2 19.795 0.34 1130 Skuld 10 29.0 0.04 13.5 +13 4.810 0.61 1102 Pepita 10 29.8 0.12 13.1 +14 5.1054 0.36 1343 Nicole 11 06.7 0.15 14.4 +16 14.76 0.42 960 Birgit 11 28.5 0.15 14.5 +22 8.85 0.28 1602 Indiana 12 09.8 0.12 14.5 +23 2.601 0.19 237 Coelestina 12 17.0 0.02 13.1 +23 29.215 0.25 86 Semele 12 19.5 0.05 11.7 +24 16.634 0.18 786 Bredichina 12 21.1 0.11 13.4 +23 29.434 0.60

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BAA Handbook 2019 Asteroids 59

NEO CLOSE APPROACHES TO EARTHPrepared from data on the Jet Propulsion Laboratory's Near Earth Object Program website at:

http://neo.jpl.nasa.gov/ca/This lists asteroids predicted to pass within 0.05 au (about 7.5 million km) of the Earth attaining magnitude 19.5 or brighter during 2019 (as of 2018 May 17). Especially favourable approaches are shown in bold. Newly-discovered objects may be added to the list available via the JPL NEO site, so do check this for recent updates. The Nominal Miss Distance is given in Lunar Distances (LD) and Astronomical Units (au). The apparent Elongation and Declination are geocentric. Ephemerides should be obtained near the time of observation from the MPC via its Minor Planet and Comet Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.htmlFor your local ephemerides, choose a location or observatory near your site. Note that the positions of some objects may be subject to significant uncertainty.

Object Close Nominal Relative Magnitude Date Elongation Declination Approach Miss Distance Velocity H (brightest) when when when Date* brightest brightest brightest LD** au km s–1 ° °2016 AZ8 Jan. 7.3 11.59 0.0298 9.15 21.0 16.4 Jan. 12 107 +682013 CW32 Jan. 29.8 13.86 0.0356 16.44 21.9 15.7 Jan. 31 167 +72013 RV9 Feb. 06.3 17.80 0.0457 5.88 23.6 19.1 Feb. 13 127 +372017 PV25 Feb. 12.5 7.26 0.0187 6.09 24.7 18.6 Feb. 17 124 –36455176 Feb. 20.7 19.14 0.0492 26.48 20.6 16.9 Feb. 18 108 +212015 EG Mar. 4.9 1.16 0.0030 9.64 25.7 15.5 Mar. 5 122 –312016 GE1 Apr. 4 3.88 0.0100 10.13 26.6 18.5 Apr. 4 133 +62016 GW221 Apr. 9 10.07 0.0259 5.30 24.8 18.3 Apr. 12 152 +182012 XO134 Apr. 18.7 14.74 0.0379 10.95 24.0 19.0 Apr. 14 135 +332016 JP Apr. 19.5 18.97 0.0488 11.50 21.1 17.3 Apr. 24 113 +272008 HS3 May 9.9 14.54 0.0374 5.28 21.7 15.3 May 8 169 –212012 KT12 May 18 3.26 0.0084 3.95 26.3 17.2 May 15 168 –2466391 May 26.0 13.48 0.0346 21.51 16.5 12.5 May 27 90 –202011 HP May 30 12.17 0.0313 8.42 22.1 16.3 May 27 147 +10441987 Jun. 24.7 7.63 0.0196 12.62 21.5 16.3 Jun. 27 101 +452008 KV2 Jun. 27.9 17.70 0.0455 11.37 21.3 17.2 Jun. 23 117 –602016 OF Jul. 7.1 12.75 0.0328 8.47 23.1 18.6 Jul. 9 98 +52016 NO56 Jul. 7 3.41 0.0088 12.20 25.7 17.7 Jul. 6 130 –142015 HM10 Jul. 24.2 12.16 0.0313 9.50 23.6 17.5 Jul. 27 157 –82010 PK9 Jul. 26.6 8.20 0.0211 16.49 21.8 14.8 Jul. 27 156 –412006 QQ23 Aug. 10.3 19.37 0.0498 4.67 20.1 16.1 Aug. 8 108 –82454094 Aug. 12.0 16.94 0.0435 8.16 21.9 19.0 Aug. 20 85 –722016 PD1 Aug. 26.3 11.38 0.0293 5.87 23.7 17.5 Aug. 24 147 +52013 CV83 Sep. 13 15.66 0.0403 13.08 23.8 19.1 Sep. 10 127 +30504800 Sep. 14.1 13.86 0.0356 14.36 21.7 16.6 Sep. 15 122 –36467317 Sep. 15.0 13.87 0.0356 6.42 19.8 14.0 Sep. 15 146 –372017 SL16 Sep. 21.1 7.91 0.0203 6.47 25.8 18.7 Sep. 25 166 +101998 FF14 Sep. 24.3 10.82 0.0278 22.26 20.7 17.8 Sep. 27 75 +51162082 Oct. 25.7 16.17 0.0416 11.21 18.9 12.3 Oct. 27 179 +132015 JD1 Nov. 3.5 12.89 0.0331 11.93 20.6 15.0 Nov. 4 134 +6481394 Nov. 21.0 11.23 0.0289 7.95 19.9 13.8 Nov. 11 178 +16216258 Dec. 20.6 15.20 0.0391 11.77 20.2 15.2 Dec. 17 134 –62017 XQ60 Dec. 22 11.00 0.0283 15.62 24.4 18.7 Dec. 21 125 –2310442 Dec. 26.3 18.97 0.0487 12.27 19.9 16.0 Dec. 30 114 –40* Dates are quoted to the nearest day if uncertainty in close approach date is greater than ±0.2 day** Lunar Distance: 1.0 LD = 3.844 x 105 km or 0.00257 AU.

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60 Jupiter BAA Handbook 2019

JUPITER Opposition: June 10 Conjunction: December 27

2019 RA Dec. Mag Equat Diam.

Polar Diam.

DE Δ h m º ' " " º au

Jan. 7 16 46.7 –21 44 –1.8 32.1 30.0 –2.8 6.14217 16 55.2 –21 58 –1.8 32.6 30.5 –2.8 6.04127 17 03.3 –22 10 –1.9 33.3 31.1 –2.8 5.924

Feb. 6 17 10.7 –22 20 –1.9 34.0 31.8 –2.8 5.79116 17 17.4 –22 27 –2.0 34.9 32.7 –2.8 5.647

26 17 23.2 –22 33 –2.0 35.9 33.6 –2.8 5.493Mar. 8 17 28.0 –22 36 –2.1 37.0 34.6 –2.8 5.333

18 17 31.7 –22 39 –2.1 38.1 35.7 –2.8 5.17128 17 34.2 –22 40 –2.2 39.3 36.8 –2.8 5.010

Apr. 7 17 35.4 –22 41 –2.3 40.6 38.0 –2.8 4.856

17 17 35.2 –22 41 –2.4 41.8 39.1 –2.8 4.71127 17 33.7 –22 40 –2.4 43.0 40.2 –2.8 4.582

May 7 17 30.9 –22 38 –2.5 44.1 41.2 –2.8 4.47117 17 27.0 –22 36 –2.5 45.0 42.1 –2.8 4.38427 17 22.3 –22 33 –2.6 45.6 42.7 –2.8 4.323

Jun. 6 17 17.0 –22 28 –2.6 46.0 43.0 –2.8 4.28916 17 11.5 –22 24 –2.6 46.0 43.0 –2.7 4.28626 17 06.2 –22 19 –2.6 45.7 42.8 –2.7 4.312

Jul. 6 17 01.4 –22 14 –2.6 45.2 42.2 –2.7 4.36616 16 57.6 –22 10 –2.5 44.3 41.5 –2.7 4.446

26 16 54.8 –22 08 –2.5 43.3 40.5 –2.7 4.548Aug. 5 16 53.2 –22 07 –2.4 42.2 39.5 –2.6 4.669

15 16 53.0 –22 09 –2.3 41.0 38.4 –2.6 4.80425 16 54.1 –22 12 –2.3 39.8 37.3 –2.6 4.949

Sep. 4 16 56.5 –22 18 –2.2 38.7 36.2 –2.5 5.100

14 17 00.1 –22 25 –2.1 37.5 35.1 –2.5 5.25324 17 04.8 –22 33 –2.1 36.5 34.1 –2.5 5.404

Oct. 4 17 10.5 –22 42 –2.0 35.5 33.2 –2.4 5.55014 17 17.2 –22 50 –2.0 34.7 32.4 –2.4 5.68724 17 24.6 –22 59 –1.9 33.9 31.7 –2.4 5.812

Nov. 3 17 32.8 –23 06 –1.9 33.3 31.1 –2.3 5.92413 17 41.5 –23 12 –1.9 32.7 30.6 –2.3 6.02023 17 50.7 –23 16 –1.9 32.3 30.2 –2.2 6.098

Dec. 3 18 00.2 –23 18 –1.8 32.0 29.9 –2.2 6.15713 18 10.0 –23 18 –1.8 31.8 29.8 –2.1 6.195

23 18 20.0 –23 15 –1.8 31.7 29.7 –2.1 6.21233 18 30.0 –23 10 –1.8 31.8 29.7 –2.0 6.207

Description of the headings in the table can be found on page 22.

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BAA Handbook 2019 Jupiter 61

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM I

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.º º º º º º º º º º º º

1 230.2 80.7 179.9 35.0 94.6 313.7 14.2 230.0 82.3 133.9 341.6 31.22 27.9 238.5 337.8 193.0 252.6 111.8 172.2 27.9 240.0 291.6 139.3 188.83 185.6 36.3 135.7 350.9 50.6 269.8 330.2 185.8 37.8 89.3 297.0 346.54 343.4 194.1 293.5 148.9 208.7 67.8 128.2 343.6 195.5 247.0 94.6 144.15 141.1 351.9 91.4 306.8 6.7 225.9 286.2 141.5 353.3 44.7 252.3 301.8

6 298.8 149.7 249.3 104.8 164.7 23.9 84.1 299.3 151.0 202.4 49.9 99.47 96.6 307.6 47.2 262.8 322.7 181.9 242.1 97.2 308.8 0.0 207.6 257.18 254.3 105.4 205.0 60.7 120.8 340.0 40.0 255.0 106.5 157.7 5.2 54.79 52.1 263.2 2.9 218.7 278.8 138.0 198.0 52.9 264.3 315.4 162.9 212.410 209.8 61.0 160.8 16.7 76.8 296.0 356.0 210.7 62.0 113.1 320.5 10.0

11 7.5 218.8 318.7 174.6 234.9 94.1 153.9 8.6 219.7 270.7 118.2 167.712 165.3 16.6 116.6 332.6 32.9 252.1 311.9 166.4 17.5 68.4 275.8 325.413 323.1 174.4 274.5 130.6 190.9 50.1 109.8 324.2 175.2 226.1 73.5 123.014 120.8 332.3 72.4 288.6 349.0 208.1 267.7 122.0 332.9 23.8 231.1 280.715 278.6 130.1 230.3 86.6 147.0 6.2 65.7 279.9 130.6 181.4 28.8 78.3

16 76.3 287.9 28.2 244.6 305.1 164.2 223.6 77.7 288.4 339.1 186.4 236.017 234.1 85.8 186.1 42.5 103.1 322.2 21.5 235.5 86.1 136.8 344.1 33.618 31.8 243.6 344.0 200.5 261.1 120.2 179.5 33.3 243.8 294.4 141.7 191.319 189.6 41.4 141.9 358.5 59.2 278.2 337.4 191.1 41.5 92.1 299.4 349.020 347.4 199.3 299.8 156.5 217.2 76.3 135.3 348.9 199.2 249.8 97.0 146.6

21 145.1 357.1 97.8 314.5 15.3 234.3 293.2 146.7 356.9 47.4 254.7 304.322 302.9 155.0 255.7 112.5 173.3 32.3 91.1 304.5 154.6 205.1 52.3 102.023 100.7 312.8 53.6 270.5 331.3 190.3 249.0 102.3 312.4 2.7 210.0 259.624 258.5 110.6 211.5 68.5 129.4 348.3 46.9 260.1 110.1 160.4 7.6 57.325 56.2 268.5 9.5 226.5 287.4 146.3 204.8 57.9 267.8 318.1 165.3 215.0

26 214.0 66.4 167.4 24.5 85.5 304.3 2.7 215.6 65.5 115.7 322.9 12.627 11.8 224.2 325.3 182.5 243.5 102.3 160.6 13.4 223.2 273.4 120.6 170.328 169.6 22.1 123.3 340.6 41.5 260.3 318.5 171.2 20.9 71.0 278.2 328.029 327.4 281.2 138.6 199.6 58.3 116.4 329.0 178.5 228.7 75.9 125.730 125.2 79.1 296.6 357.6 216.3 274.3 126.7 336.2 26.3 233.5 283.331 283.0 237.1 155.7 72.2 284.5 184.0 81.0

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h º h º º m º m m º 1 36.58 7 256.05 10 6.10 1 0.61 6 3.66 2 73.16 8 292.63 20 12.19 2 1.22 7 4.27 3 109.74 9 329.21 30 18.29 3 1.83 8 4.88 4 146.32 10 365.79 40 24.39 4 2.44 9 5.49 5 182.90 11 402.37 50 30.48 5 3.05 10 6.10 6 219.48 12 438.95 60 36.58System I applies to all objects situated on or between the north component of the South Equatorial Belt and the south component of the North Equatorial Belt.

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62 Jupiter BAA Handbook 2019

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM II

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.º º º º º º º º º º º º

1 178.2 152.3 37.8 16.4 207.0 189.6 21.2 0.5 336.2 159.0 130.2 310.82 328.3 302.4 188.0 166.7 357.4 340.0 171.6 150.7 126.3 309.1 280.2 100.83 118.4 92.6 338.3 317.0 147.8 130.4 321.9 301.0 276.5 99.1 70.2 250.94 268.5 242.8 128.5 107.3 298.2 280.8 112.3 91.2 66.6 249.2 220.3 40.95 58.6 33.0 278.8 257.6 88.6 71.2 262.6 241.4 216.7 39.2 10.3 190.9

6 208.8 183.1 69.0 48.0 239.0 221.6 52.9 31.6 6.8 189.3 160.3 340.97 358.9 333.3 219.3 198.3 29.4 12.0 203.3 181.9 156.9 339.3 310.3 131.08 149.0 123.5 9.5 348.6 179.8 162.4 353.6 332.1 307.1 129.4 100.4 281.09 299.1 273.7 159.8 139.0 330.2 312.8 143.9 122.3 97.2 279.4 250.4 71.010 89.2 63.8 310.0 289.3 120.6 103.2 294.3 272.5 247.3 69.5 40.4 221.0

11 239.3 214.0 100.3 79.7 271.0 253.6 84.6 62.7 37.4 219.5 190.4 11.112 29.4 4.2 250.5 230.0 61.4 44.0 234.9 212.9 187.5 9.6 340.4 161.113 179.6 154.4 40.8 20.4 211.8 194.4 25.2 3.1 337.6 159.6 130.5 311.114 329.7 304.6 191.1 170.7 2.2 344.8 175.5 153.3 127.7 309.6 280.5 101.115 119.8 94.8 341.3 321.1 152.6 135.2 325.8 303.5 277.8 99.7 70.5 251.2

16 269.9 245.0 131.6 111.4 303.0 285.6 116.1 93.7 67.9 249.7 220.5 41.217 60.1 35.2 281.9 261.8 93.4 76.0 266.4 243.9 218.0 39.7 10.5 191.218 210.2 185.4 72.2 52.1 243.8 226.4 56.7 34.0 8.0 189.8 160.6 341.319 0.3 335.6 222.5 202.5 34.2 16.8 207.0 184.2 158.1 339.8 310.6 131.320 150.5 125.8 12.7 352.9 184.6 167.2 357.3 334.4 308.2 129.9 100.6 281.3

21 300.6 276.0 163.0 143.2 335.1 317.5 147.6 124.6 98.3 279.9 250.6 71.422 90.8 66.2 313.3 293.6 125.5 107.9 297.9 274.7 248.4 69.9 40.6 221.423 240.9 216.5 103.6 84.0 275.9 258.3 88.2 64.9 38.5 220.0 190.6 11.424 31.0 6.7 253.9 234.3 66.3 48.7 238.4 215.0 188.5 10.0 340.7 161.525 181.2 156.9 44.2 24.7 216.7 199.0 28.7 5.2 338.6 160.0 130.7 311.5

26 331.3 307.1 194.5 175.1 7.1 349.4 179.0 155.4 128.7 310.0 280.7 101.627 121.5 97.4 344.8 325.5 157.5 139.8 329.2 305.5 278.7 100.1 70.7 251.628 271.6 247.6 135.1 115.9 307.9 290.1 119.5 95.7 68.8 250.1 220.8 41.629 61.8 285.4 266.2 98.3 80.5 269.7 245.8 218.9 40.1 10.8 191.730 212.0 75.7 56.6 248.8 230.9 60.0 35.9 8.9 190.1 160.8 341.7

31 2.1 226.0 39.2 210.2 186.1 340.2 131.8

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º

1 36.26 7 253.83 10 6.04 1 0.60 6 3.63 2 72.52 8 290.09 20 12.09 2 1.21 7 4.23 3 108.78 9 326.35 30 18.13 3 1.81 8 4.83 4 145.05 10 362.61 40 24.17 4 2.42 9 5.44 5 181.31 11 398.87 50 30.22 5 3.02 10 6.04 6 217.57 12 435.14 60 36.26System II applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt.

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BAA Handbook 2019 Jupiter 63

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM III (2009)

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.º º º º º º º º º º º º

1 110.2 92.5 345.6 332.4 171.0 161.8 1.5 349.0 333.0 163.8 143.3 331.92 260.6 243.0 136.1 122.9 321.7 312.5 152.1 139.5 123.4 314.1 293.5 122.23 51.0 33.4 286.6 273.5 112.3 103.2 302.7 290.0 273.8 104.4 83.8 272.54 201.3 183.9 77.1 64.1 263.0 253.9 93.3 80.5 64.2 254.8 234.1 62.75 351.7 334.3 227.6 214.7 53.7 44.5 243.9 231.0 214.6 45.1 24.4 213.0

6 142.1 124.7 18.1 5.3 204.3 195.2 34.5 21.5 5.0 195.4 174.7 3.37 292.5 275.2 168.6 155.9 355.0 345.9 185.1 172.0 155.3 345.7 325.0 153.68 82.8 65.6 319.1 306.5 145.6 136.6 335.7 322.5 305.7 136.0 115.3 303.99 233.2 216.1 109.6 97.1 296.3 287.2 126.3 113.0 96.1 286.3 265.6 94.210 23.6 6.5 260.2 247.7 87.0 77.9 276.9 263.4 246.5 76.7 55.9 244.5

11 174.0 157.0 50.7 38.3 237.6 228.6 67.5 53.9 36.8 227.0 206.1 34.812 324.4 307.4 201.2 188.9 28.3 19.2 218.1 204.4 187.2 17.3 356.4 185.113 114.8 97.9 351.7 339.6 179.0 169.9 8.7 354.8 337.6 167.6 146.7 335.414 265.2 248.3 142.3 130.2 329.7 320.6 159.3 145.3 127.9 317.9 297.0 125.715 55.6 38.8 292.8 280.8 120.3 111.2 309.8 295.8 278.3 108.2 87.3 276.0

16 205.9 189.3 83.4 71.4 271.0 261.9 100.4 86.2 68.7 258.5 237.6 66.317 356.3 339.7 233.9 222.0 61.7 52.5 251.0 236.7 219.0 48.8 27.9 216.618 146.7 130.2 24.4 12.7 212.4 203.2 41.5 27.1 9.4 199.1 178.1 6.919 297.1 280.7 175.0 163.3 3.0 353.8 192.1 177.6 159.7 349.4 328.4 157.220 87.5 71.2 325.5 313.9 153.7 144.5 342.7 328.0 310.1 139.7 118.7 307.5

21 238.0 221.6 116.1 104.6 304.4 295.1 133.2 118.4 100.4 290.0 269.0 97.822 28.4 12.1 266.6 255.2 95.1 85.8 283.8 268.9 250.8 80.3 59.3 248.123 178.8 162.6 57.2 45.8 245.7 236.4 74.3 59.3 41.1 230.6 209.6 38.424 329.2 313.1 207.8 196.5 36.4 27.1 224.8 209.7 191.5 20.9 359.9 188.725 119.6 103.6 358.3 347.1 187.1 177.7 15.4 0.1 341.8 171.2 150.2 339.0

26 270.0 254.1 148.9 137.8 337.8 328.3 165.9 150.6 132.1 321.5 300.4 129.327 60.4 44.6 299.5 288.4 128.5 119.0 316.4 301.0 282.5 111.8 90.7 279.628 210.8 195.1 90.0 79.1 279.1 269.6 107.0 91.4 72.8 262.1 241.0 69.929 1.3 240.6 229.7 69.8 60.2 257.5 241.8 223.1 52.4 31.3 220.230 151.7 31.2 20.4 220.5 210.9 48.0 32.2 13.5 202.7 181.6 10.5

31 302.1 181.8 11.2 198.5 182.6 353.0 160.8

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 36.27 7 253.91 10 6.05 1 0.60 6 3.63 2 72.54 8 290.18 20 12.09 2 1.21 7 4.23 3 108.82 9 326.45 30 18.14 3 1.81 8 4.84 4 145.09 10 362.72 40 24.18 4 2.42 9 5.44 5 181.36 11 399.00 50 30.23 5 3.02 10 6.05 6 217.63 12 435.27 60 36.27System III applies to the origin of radio emissions from the planet. See page 64 for a description.

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64 Satellites of Jupiter BAA Handbook 2019

SATELLITES OF JUPITER

The satellites move from east to west across the face of the planet, and from west to east behind it. After conjunction with the Sun and before opposition, the shadow of Jupiter falls to the west, eclipse precedes occultation, and shadow–transit precedes transit. After opposition, the order of phenomena is reversed, occultation preceding eclipse and transit preceding shadow–transit.

Both phases of eclipse (EcD and EcR) and of occultation (OcD and OcR) of satellites III and IV may be seen if not too near opposition. Satellite I is much closer to the planet, and eclipse and occultation merge into one, OcD being followed by EcR after opposition and before conjunction, while EcD is followed by OcR after conjunction and before opposition. Satellite II normally behaves in the same manner but on rare occasions the separate phenomena of II may be observed. This happens when the planet is near quadrature and is tilted at almost the maximum amount.

On a few occasions all three of the inner satellites may be involved simultaneously in these phenomena. The motions of these three satellites are related in such a way that it is impossible for all three to undergo the same phenomenon at the same time.

The Institut de Mécanique Céleste et de Calcul des Ephémérides supplies event timings in Terrestrial Time (TT). These have been converted to Universal Time (UT), closely, by subtracting one minute (see tables on p.67–76), since ΔT is just over one minute now. The times of phenomena are given for the centre of the satellite. The light of the satellite will therefore begin to fade before the times given here, and observation should commence several minutes before the predicted times.

Charts are included for all 12 months of the year, even though Jupiter will be in conjunction with the Sun on October 26, and therefore not observable for a few weeks either side of this date.

For all charts the satellites are labelled: I Io II Europa III Ganymede IV Callisto

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM III – DEFINITION

Radio radiation from Jupiter at around 20MHz was discovered in 1955. It varies with the rotation of the planet and this is known as "System III". It is of interest because it indicates rotation beneath the cloud cover. Radio radiation emanates from the magnetosphere of Jupiter, and the rotation is due to the fact that the magnetic poles are not situated exactly at the poles of rotation. (The position of the satellite Io and the DE value are also significant for predicting "radio storms" from Jupiter.) In 1976 the IAU adopted a rotation for System III of 870.536 degrees per day. More recent work suggested an improvement to 870.536642, adopted in 2000 and used in recent BAA Handbooks. However subsequent analysis of data from Galileo gives a different value, consistent with 870.536 and its implied accuracy but not with 870.536642. The IAU provisionally recommends that 870.536 be used.

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BAA Handbook 2019 Satellites of Jupiter 65

SAT

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66 Satellites of Jupiter BAA Handbook 2019

SAT

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BAA Handbook 2019 Satellites of Jupiter 67

SAT

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68 Satellites of Jupiter BAA Handbook 2019

SAT

EL

LIT

ES

OF

JU

PIT

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201

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BAA Handbook 2019 Satellites of Jupiter 69

ECLIPSES, OCCULTATIONS AND TRANSITSThe times are for mid–phenomena, i.e. for eclipses, the planet’s shadow bisecting the satellite; for other events, Jupiter’s limb bisecting the satellite or the satellite shadow.

Abbreviations: OcD and OcR occultation disappearance and reappearance EcD and EcR eclipse disappearance and reappearance TrI and TrE transit ingress and egress ShI and ShE shadow–transit ingress and egress

January

Occultations and Eclipses Date Sat. EcD EcR OcD OcR 1 I 04 08 06 55 1/2 III 22 37 00 36 01 01 03 09 2/3 I 22 36 01 25 4 II 08 54 12 36 4 I 17 05 19 55 6 I 11 33 14 25 7/8 II 22 12 02 00 8 I 06 02 08 55 9 III 02 35 04 35 05 25 07 33 10 I 00 30 03 25 11 II 11 30 15 24 11 I 18 58 21 55 13 I 13 27 16 24 15 II 00 48 04 48 15 I 07 55 10 54 16 III 06 32 08 33 09 48 11 56 17 I 02 23 05 24 18 II 14 05 18 12 18 I 20 52 23 54 20 I 15 20 18 23 22 II 03 23 07 36 22 I 09 48 12 53 23 III 10 31 12 33 14 09 16 18 24 I 04 17 07 23 25 II 16 40 20 59 25/26 I 22 45 01 52 27 I 17 13 20 22 29 II 05 58 10 22 29 I 11 41 14 51 30 III 14 28 16 31 18 27 20 37 31 I 06 10 09 21

January Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 2 I 01 16 03 27 01 52 04 04 2 II 14 43 17 03 15 56 18 18 3 I 19 45 21 55 20 23 22 34 5 III 12 22 14 20 14 59 17 06 5 I 14 13 16 24 14 53 17 04 6 II 04 01 06 20 05 19 07 42 7 I 08 42 10 52 09 23 11 34 9 I 03 10 05 21 03 53 06 04 9 II 17 18 19 37 18 43 21 05 10/11 I 21 39 23 49 22 23 00 34 12 I 16 07 18 18 16 53 19 04 12 III 16 20 18 19 19 23 21 30 13 II 06 35 08 54 08 05 10 28 14 I 10 35 12 46 11 23 13 34 16 I 05 04 07 15 05 52 08 04 16 II 19 51 22 11 21 28 23 51 17/18 I 23 32 01 43 00 22 02 33 19 I 18 01 20 11 18 52 21 03 19/20 III 20 17 22 17 23 44 01 51 20 II 09 08 11 28 10 50 13 13 21 I 12 29 14 40 13 22 15 33 23 I 06 58 09 08 07 52 10 03 23/24 II 22 25 00 45 00 13 02 35 25 I 01 26 03 37 02 22 04 33 26 I 19 55 22 05 20 51 23 02 27 III 00 14 02 15 04 04 06 11 27 II 11 42 14 02 13 34 15 57 28 I 14 23 16 34 15 21 17 32 30 I 08 51 11 02 09 51 12 02 31 II 00 59 03 19 02 56 05 19

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70 Satellites of Jupiter BAA Handbook 2019

ECLIPSES, OCCULTATIONS AND TRANSITSFebruary Occultations and Eclipses Date Sat. EcD EcR OcD OcR

1 II 19 16 23 45 2 I 00 38 03 50 3 I 19 06 22 20 5 II 08 34 13 08 5 I 13 35 16 49 6/7 III 18 25 20 29 22 43 00 53 7 I 08 03 11 18 8/9 II 21 51 02 30 9 I 02 31 05 48 10/11 I 20 59 00 17 12 II 11 09 15 52 12 I 15 28 18 46 13/14 III 22 22 00 27 02 56 05 07 14 I 09 56 13 15 16 II 00 27 05 13 16 I 04 24 07 44 17/18 I 22 52 02 13 19 II 13 45 16 08 16 09 18 35 19 I 17 21 20 42 21 III 02 19 04 24 07 06 09 17 21 I 11 49 15 11 23 II 03 02 05 25 05 29 07 55 23 I 06 17 09 40 25 I 00 45 04 09 26 II 16 20 18 44 18 50 21 16 26 I 19 14 22 38 28 III 06 16 08 23 11 13 13 25 28 I 13 42 17 07

February Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

1 I 03 20 05 30 04 20 06 31 2/ 3 I 21 48 23 59 22 50 01 01 3 III 04 13 06 14 08 22 10 30 3 II 14 15 16 35 16 17 18 40 4 I 16 17 18 27 17 19 19 30 6 I 10 45 12 56 11 49 14 00 7 II 03 32 05 52 05 38 08 01 8 I 05 14 07 24 06 18 08 29 9/10 I 23 42 01 53 00 48 02 59 10 III 08 10 10 12 12 37 14 45 10 II 16 49 19 09 18 58 21 21 11 I 18 10 20 21 19 17 21 28 13 I 12 39 14 49 13 46 15 57 14 II 06 05 08 26 08 18 10 41 15 I 07 07 09 18 08 16 10 27 17 I 01 36 03 46 02 45 04 56 17 III 12 09 14 12 16 50 18 59 17/18 II 19 22 21 42 21 38 00 01 18 I 20 04 22 15 21 14 23 25 20 I 14 32 16 43 15 43 17 54 21 II 08 38 10 59 10 58 13 20 22 I 09 01 11 11 10 12 12 23 24 I 03 29 05 40 04 41 06 52 24 III 16 06 18 10 20 59 23 08 24/25 II 21 55 00 15 00 17 02 39 25/26 I 21 58 00 08 23 10 01 21 27 I 16 26 18 37 17 39 19 50 28 II 11 11 13 32 13 35 15 58

March Occultations and Eclipses Date Sat. EcD EcR OcD OcR 2 II 05 38 08 01 08 09 10 36 2 I 08 10 11 35 4 I 02 38 06 04 5 II 18 56 21 20 21 29 23 56 5/6 I 21 07 00 32 7 III 10 13 12 21 15 17 17 29 7 I 15 35 19 01 9 II 08 14 10 37 10 48 13 14 9 I 10 03 13 29 11 I 04 31 07 58

March Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 1 I 10 54 13 05 12 08 14 19 3 I 05 23 07 33 06 37 08 48 3/ 4 III 20 04 22 09 01 05 03 14 4 II 00 28 02 48 02 53 05 16 4/ 5 I 23 51 02 02 01 06 03 17 6 I 18 20 20 30 19 34 21 45 7 II 13 44 16 05 16 11 18 34 8 I 12 48 14 59 14 03 16 14 10 I 07 16 09 27 08 32 10 43 11 III 00 01 02 07 05 07 07 16

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BAA Handbook 2019 Satellites of Jupiter 71

ECLIPSES, OCCULTATIONS AND TRANSITS

March cont'd Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 11 II 03 00 05 21 05 28 07 51 12 I 01 45 03 55 03 00 05 11 13 I 20 13 22 24 21 29 23 40 14 II 16 17 18 38 18 45 21 08 15 I 14 42 16 52 15 57 18 08 17 I 09 10 11 21 10 25 12 36 18 III 03 58 06 05 09 05 11 14 18 II 05 33 07 55 08 01 10 24 19 I 03 38 05 49 04 54 07 05 20/21 I 22 07 00 17 23 22 01 33 21 II 18 50 21 11 21 17 23 40 22 I 16 35 18 46 17 50 20 01 24 I 11 04 13 14 12 18 14 29 25 III 07 56 10 04 12 59 15 09 25 II 08 06 10 28 10 32 12 55 26 I 05 32 07 43 06 46 08 57 28 I 00 00 02 11 01 14 03 25 28/29 II 21 22 23 44 23 47 02 10 29 I 18 29 20 39 19 42 21 53 31 I 12 57 15 08 14 10 16 21

April Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 1 II 10 39 13 01 13 01 15 24 1 III 11 54 14 03 16 49 18 59 2 I 07 25 09 36 08 38 10 49 4 I 01 54 04 05 03 05 05 16 4/ 5 II 23 55 02 17 02 15 04 38 5 I 20 22 22 33 21 33 23 44 7 I 14 51 17 02 16 01 18 12 8 II 13 11 15 34 15 28 17 51 8 III 15 52 18 02 20 35 22 45 9 I 09 19 11 30 10 28 12 39 11 I 03 47 05 58 04 56 07 07 12 II 02 28 04 50 04 40 07 04 12/13 I 22 16 00 27 23 23 01 34 14 I 16 44 18 55 17 50 20 01 15 II 15 44 18 07 17 53 20 16 15/16 III 19 50 22 01 00 16 02 26

March cont'd Occultations and Eclipses Date Sat. EcD EcR OcD OcR

12/13 II 21 32 23 56 00 07 02 33 12/13 I 22 59 02 26 14 III 14 11 16 20 19 18 21 30 14 I 17 28 20 54 16 II 10 49 13 14 13 24 15 51 16 I 11 56 15 23 18 I 06 24 09 51 20 II 00 08 02 32 02 42 05 09 20 I 00 52 04 19 21/22 III 18 08 20 18 23 13 01 26 21 I 19 21 22 47 23 II 13 25 15 50 15 59 18 25 23 I 13 49 17 15 25 I 08 17 11 43 27 II 02 43 05 08 05 16 07 42 27 I 02 45 06 11 28/29 I 21 13 00 38 28/29 III 22 05 00 16 03 05 05 17 30 I 15 42 19 06 30 II 16 01 18 26 18 31 20 58

April Occultations and Eclipses Date Sat. EcD EcR OcD OcR 1 I 10 10 13 34 3 I 04 38 08 01 3 II 05 19 07 44 07 47 10 14 4/5 I 23 06 02 29 5 III 02 02 04 14 06 51 09 04 6 I 17 35 20 56 6 II 18 37 23 28 8 I 12 03 15 24 10 I 06 31 09 51 10 II 07 55 12 43 12 I 00 59 04 18 12 III 05 59 08 12 10 34 12 46 13 I 19 28 22 45 13/14 II 21 13 01 56 15 I 13 56 17 13

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72 Satellites of Jupiter BAA Handbook 2019

ECLIPSES, OCCULTATIONS AND TRANSITS

April cont'd Occultations and Eclipses Date Sat. EcD EcR OcD OcR 17 I 08 24 11 40 17 II 10 31 15 09 19 I 02 52 06 07 19 III 09 57 12 10 14 12 16 24 20/21 I 21 21 00 34 20/21 II 23 48 04 21 22 I 15 49 19 00 24 I 10 17 13 27 24 II 13 07 17 34 26 I 04 45 07 54 26 III 13 54 16 09 17 46 19 58 27/28 I 23 14 02 21 28 II 02 24 06 45 29 I 17 42 20 47

May Occultations and Eclipses Date Sat. EcD EcR OcD OcR

1 I 12 10 15 14 1 II 15 43 19 56 3 I 06 39 09 40 3 III 17 52 20 08 21 17 23 28 5 I 01 07 04 07 5 II 05 00 09 06 6 I 19 35 22 33 8 I 14 04 17 00 8 II 18 19 22 16 10 I 08 32 11 26 10/11 III 21 50 00 07 00 42 02 54 12 I 03 00 05 52 12 II 07 36 11 25 13/14 I 21 29 00 18 15 I 15 57 18 45 15/16 II 20 55 00 35 17 I 10 25 13 11 18 III 01 47 06 16 19 I 04 54 07 37 19 II 10 12 13 43 20/21 I 23 22 02 03

April cont'd Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 16 I 11 12 13 24 12 17 14 28 18 I 05 41 07 52 06 45 08 56 19 II 05 00 07 24 07 04 09 28 20 I 00 09 02 20 01 12 03 23 21 I 18 38 20 49 19 39 21 50 22 II 18 17 20 40 20 15 22 39 22/23 III 23 47 02 00 03 52 06 02 23 I 13 06 15 17 14 06 16 17 25 I 07 35 09 46 08 33 10 44 26 II 07 33 09 57 09 26 11 50 27 I 02 03 04 14 02 59 05 11 28 I 20 31 22 43 21 26 23 37 29/30 II 20 50 23 14 22 36 01 00 30 III 03 44 05 58 07 23 09 33 30 I 15 00 17 11 15 53 18 04

May Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

2 I 09 28 11 40 10 20 12 31 3 II 10 06 12 31 11 46 14 10 4 I 03 57 06 08 04 46 06 57 5/ 6 I 22 25 00 37 23 13 01 24 6/ 7 II 23 23 01 48 00 55 03 19 7 III 07 42 09 57 10 51 13 01 7 I 16 53 19 05 17 39 19 51 9 I 11 22 13 34 12 06 14 17 10 II 12 40 15 05 14 04 16 28 11 I 05 50 08 02 06 32 08 43 13 I 00 19 02 31 00 58 03 10 14 II 01 56 04 22 03 12 05 36 14 III 11 40 13 56 14 15 16 25 14 I 18 47 20 59 19 25 21 36 16 I 13 16 15 28 13 51 16 02 17 II 15 13 17 39 16 20 18 44 18 I 07 44 09 56 08 17 10 29 20 I 02 13 04 25 02 43 04 55 21 II 04 30 06 56 05 28 07 52 21 III 15 38 17 55 17 37 19 47 21 I 20 41 22 53 21 09 23 21

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BAA Handbook 2019 Satellites of Jupiter 73

ECLIPSES, OCCULTATIONS AND TRANSITS May cont'd Occultations and Eclipses Date Sat. EcD EcR OcD OcR 22 I 17 51 20 29 22/23 II 23 31 02 52 24 I 12 19 14 55 25 III 05 45 09 35 26 I 06 47 09 21 26 II 12 48 16 00 28 I 01 16 03 47 29 I 19 44 22 13 30 II 02 07 05 08 31 I 14 13 16 39

June

Occultations and Eclipses Date Sat. EcD EcR OcD OcR

1 III 09 42 12 53 2 I 08 41 11 05 2 II 15 25 18 15 4 I 03 10 05 31 5 I 21 38 23 57 6 II 04 43 07 23 7 I 16 06 18 23 8 III 13 41 16 10 9 I 10 35 12 48 9 II 18 01 20 30

May cont'd Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

23 I 15 10 17 22 15 36 17 47 24 II 17 47 20 13 18 35 21 00 25 I 09 38 11 50 10 02 12 13 27 I 04 07 06 19 04 28 06 39 28 II 07 04 09 30 07 43 10 07 28 III 19 37 21 55 20 56 23 06 28/29 I 22 35 00 47 22 54 01 05 30 I 17 04 19 16 17 20 19 31 31 II 20 21 22 47 20 50 23 14

June Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

1 I 11 32 13 44 11 46 13 57 3 I 06 01 08 13 06 12 08 23 4 II 09 38 12 05 09 57 12 22 4/ 5 III 23 35 01 55 00 13 02 23 5 I 00 29 02 42 00 38 02 49 6 I 18 58 21 10 19 04 21 15 7/ 8 II 22 55 01 22 23 04 01 29 8 I 13 26 15 39 13 30 15 41 10 I 07 55 10 07 07 56 10 07

Jupiter in Opposition to the Sun: 2019 June 10d 15h

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74 Satellites of Jupiter BAA Handbook 2019

ECLIPSES, OCCULTATIONS AND TRANSITS

June cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

11 II 12 11 14 36 12 12 14 40 12 I 02 22 04 33 02 24 04 36 12 III 03 28 05 40 03 33 05 54 13 I 20 48 22 59 20 52 23 05 15 II 01 18 03 43 01 30 03 57 15 I 15 14 17 25 15 21 17 33 17 I 09 40 11 51 09 49 12 02 18 II 14 25 16 50 14 47 17 15 19 I 04 06 06 17 04 18 06 30 19 III 06 44 08 57 07 31 09 53 20/21 I 22 32 00 43 22 47 00 59 22 II 03 32 05 57 04 04 06 32 22 I 16 58 19 10 17 15 19 28 24 I 11 24 13 36 11 44 13 56 25 II 16 40 19 05 17 22 19 50 26 I 05 50 08 02 06 13 08 25 26 III 10 02 12 15 11 30 13 53 28 I 00 16 02 28 00 41 02 53 29 II 05 48 08 13 06 40 09 08 29 I 18 43 20 54 19 10 21 22

June cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

11 I 05 03 07 15 12/13 I 23 29 01 44 13 II 07 12 09 47 14 I 17 55 20 13 15 III 17 14 20 02 16 I 12 21 14 41 16 II 20 20 23 05 18 I 06 47 09 10 20 I 01 13 03 38 20 II 09 27 12 24 21 I 19 39 22 07 22/23 III 20 31 00 02 23 I 14 05 16 35 23/24 II 22 35 01 42 25 I 08 31 11 04 27 I 02 57 05 33 27 II 11 43 15 00 28/29 I 21 23 00 01 29/30 III 23 49 04 02 30 I 15 49 18 30

July Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 II 00 51 04 18 2 I 10 16 12 58 4 I 04 42 07 27 4 II 14 00 17 36 5/6 I 23 08 01 56 7 III 03 10 05 27 05 35 08 01 7 I 17 35 20 25 8 II 03 09 06 54 9 I 12 01 14 53 11 I 06 28 09 22 11 II 16 18 20 13 13 I 00 54 03 51 14 III 06 33 08 51 09 34 12 01 14 I 19 21 22 19 15 II 05 28 09 31

July Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 I 13 09 15 21 13 39 15 51 2 II 18 56 21 21 19 57 22 26 3 I 07 35 09 47 08 07 10 19 3 III 13 21 15 36 15 29 17 53 5 I 02 02 04 13 02 36 04 48 6 II 08 04 10 30 09 15 11 44 6 I 20 28 22 40 21 04 23 17 8 I 14 55 17 06 15 33 17 45 9/10 II 21 13 23 39 22 33 01 02 10 I 09 21 11 33 10 02 12 14 10 III 16 44 19 00 19 28 21 53 12 I 03 48 05 59 04 31 06 43 13 II 10 23 12 48 11 51 14 20 13/14 I 22 14 00 26 22 59 01 11 15 I 16 41 18 52 17 28 19 40

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BAA Handbook 2019 Satellites of Jupiter 75

ECLIPSES, OCCULTATIONS AND TRANSITS

July cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

16 I 13 47 16 48 18 I 08 14 11 17 18 II 18 38 22 49 20 I 02 41 05 45 21 III 10 00 12 20 13 33 16 01 21/22 I 21 08 00 14 22 II 07 49 12 07 23 I 15 35 18 43 25 I 10 02 13 12 25/26 II 21 00 01 25 27 I 04 29 07 40 28 III 13 32 15 53 17 32 20 01 28/29 I 22 56 02 09 29 II 10 12 14 43 30 I 17 23 20 38

July cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

16/17 II 23 33 01 58 01 09 03 38 17 I 11 08 13 19 11 57 14 09 17/18 III 20 10 22 27 23 27 01 54 19 I 05 35 07 46 06 25 08 37 20 II 12 43 15 09 14 27 16 56 21 I 00 02 02 13 00 54 03 06 22 I 18 29 20 40 19 23 21 35 24 II 01 54 04 20 03 45 06 14 24 I 12 56 15 07 13 51 16 03 24/25 III 23 39 01 58 03 26 05 54 26 I 07 23 09 34 08 20 10 32 27 II 15 05 17 32 17 03 19 32 28 I 01 50 04 01 02 49 05 01 29 I 20 17 22 28 21 18 23 29 31 II 04 17 06 44 06 21 08 51 31 I 14 44 16 56 15 46 17 58

August Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 I 11 51 15 07 1/2 II 23 24 04 01 3 I 06 18 09 36 4/5 III 17 08 19 31 21 31 00 02 5 I 00 45 04 04 5 II 12 37 17 19 6 I 19 13 22 33 8 I 13 41 17 02 9 II 01 50 06 37 10 I 08 08 11 31 11/12 III 20 49 23 14 01 31 04 03 12 I 02 36 06 00 12 II 15 04 19 55 13/14 I 21 04 00 28 15 I 15 32 18 57 16 II 04 18 09 13 17 I 10 00 13 26 19 III 00 34 03 00 05 31 08 04 19 I 04 28 07 55

August Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 III 03 13 05 33 07 25 09 53 2 I 09 12 11 23 10 15 12 27 3 II 17 30 19 57 19 39 22 09 4 I 03 39 05 50 04 44 06 55 5/ 6 I 22 07 00 18 23 12 01 24 7 II 06 43 09 10 08 58 11 28 7 I 16 34 18 45 17 41 19 53 8 III 06 51 09 13 11 24 13 53 9 I 11 02 13 13 12 10 14 21 10/11 II 19 57 22 24 22 16 00 46 11 I 05 30 07 41 06 39 08 50 12/13 I 23 57 02 09 01 07 03 19 14 II 09 12 11 39 11 35 14 05 14 I 18 25 20 36 19 36 21 48 15 III 10 33 12 57 15 23 17 53 16 I 12 53 15 04 14 05 16 16 17/18 II 22 26 00 54 00 53 03 23 18 I 07 21 09 32 08 34 10 45 20 I 01 49 04 00 03 02 05 14

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76 Satellites of Jupiter BAA Handbook 2019

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September Occultations and Eclipses Date Sat. OcD OcR EcD EcR

2 I 08 15 11 46 2 III 08 17 10 47 13 29 16 04 2/3 II 22 37 01 07 01 11 03 43 4 I 02 43 06 15 5/6 I 21 12 00 44 6 II 11 55 14 24 14 28 17 00 7 I 15 41 19 12 9 I 10 10 13 41 9 III 12 15 14 46 17 28 20 04 10 II 01 12 03 42 03 46 06 18 11 I 04 38 08 10 12/13 I 23 07 02 39 13 II 14 31 17 01 17 04 19 36 14 I 17 36 21 08 16 I 12 06 15 37 16/17 III 16 18 18 50 21 28 00 06 17 II 03 49 06 20 06 21 08 54 18 I 06 35 10 06 20 I 01 04 04 35 20 II 17 08 22 12 21 I 19 33 23 03 23 I 14 03 17 32 23/24 III 20 24 22 58 01 28 04 06 24 II 06 28 11 29

September Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 II 03 32 06 01 06 07 08 38 1 I 11 07 13 18 12 23 14 35 3 I 05 36 07 47 06 52 09 04 4 II 16 50 19 19 19 26 21 58 5 I 00 05 02 16 01 21 03 32 5/ 6 III 22 09 00 38 03 22 05 56 6 I 18 33 20 44 19 50 22 01 8 II 06 08 08 37 08 44 11 16 8 I 13 02 15 13 14 18 16 30 10 I 07 31 09 42 08 47 10 59 11/12 II 19 28 21 57 22 03 00 36 12 I 02 00 04 11 03 16 05 27 13 III 02 10 04 39 07 21 09 56 13 I 20 29 22 40 21 45 23 56 15 II 08 47 11 16 11 22 13 54 15 I 14 58 17 09 16 13 18 25 17 I 09 27 11 38 10 42 12 54 18/19 II 22 07 00 37 00 41 03 14 19 I 03 56 06 07 05 11 07 22 20 III 06 13 08 44 11 20 13 56 20/21 I 22 25 00 36 23 39 01 51 22 II 11 27 13 57 13 59 16 32 22 I 16 54 19 05 18 08 20 20 24 I 11 23 13 34 12 37 14 49

August cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

19 II 17 33 22 31 20/21 I 22 56 02 24 22 I 17 24 20 53 23 II 06 48 09 17 09 17 11 49 24 I 11 52 15 21 26 III 04 23 06 51 09 30 12 04 26 I 06 21 09 50 26/27 II 20 04 22 33 22 35 01 07 28 I 00 49 04 19 29 I 19 17 22 48 30 II 09 20 11 50 11 53 14 25 31 I 13 46 17 17

August cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

21 II 11 42 14 10 14 12 16 42 21 I 20 17 22 28 21 31 23 42 22 III 14 21 16 46 19 23 21 54 23 I 14 46 16 57 16 00 18 11 25 II 00 58 03 26 03 30 06 01 25 I 09 14 11 25 10 28 12 40 27 I 03 42 05 53 04 57 07 09 28 II 14 15 16 43 16 49 19 20 28/29 I 22 10 00 22 23 26 01 37 29/30 III 18 13 20 39 23 22 01 54 30 I 16 39 18 50 17 55 20 06

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BAA Handbook 2019 Satellites of Jupiter 77

ECLIPSES, OCCULTATIONS AND TRANSITS

September cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

25 I 08 32 12 01 27 I 03 01 06 30 27/28 II 19 48 00 47 28/29 I 21 31 00 59 30 I 16 00 19 28

September cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

26 II 00 48 03 19 03 19 05 52 26 I 05 52 08 04 07 06 09 17 27 III 10 20 12 53 15 19 17 56 28 I 00 22 02 33 01 34 03 46 29 II 14 09 16 40 16 37 19 11 29 I 18 51 21 02 20 03 22 15

October Occultations and Eclipses Date Sat. OcD OcR EcD EcR 1 III 00 34 03 09 05 28 08 08 1 II 09 08 14 05 2 I 10 30 13 57 4 I 04 59 08 26 4/5 II 22 29 03 22 5/6 I 23 29 02 54 7 I 17 59 21 23 8 III 04 46 07 23 09 28 12 09 8 II 11 49 16 40 9 I 12 29 15 52 11 I 06 58 10 21 12 II 01 11 05 57 13 I 01 28 04 50 14 I 19 58 23 19 15 III 09 02 11 40 13 27 16 09 15 II 14 32 19 15 16 I 14 28 17 48 18 I 08 58 12 17 19 II 03 54 08 33 20 I 03 28 06 45 21/22 I 21 58 01 14 22 III 13 19 15 59 17 26 20 09 22 II 17 16 21 50 23 I 16 28 19 43 25 I 10 58 14 12 26 II 06 38 11 08 27 I 05 28 08 41 28/29 I 23 58 03 10 29/30 III 17 39 20 21 21 25 00 10 29/30 II 20 01 00 25 30 I 18 28 21 38

October Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 I 13 20 15 32 14 32 16 44 3 II 03 31 06 02 05 56 08 30 3 I 07 50 10 01 09 00 11 12 4 III 14 31 17 05 19 18 21 56 5 I 02 19 04 31 03 29 05 41 6 II 16 53 19 24 19 15 21 49 6/ 7 I 20 49 23 00 21 58 00 10 8 I 15 18 17 30 16 27 18 38 10 II 06 15 08 48 08 34 11 09 10 I 09 48 12 00 10 55 13 07 11/12 III 18 45 21 20 23 18 01 57 12 I 04 18 06 29 05 24 07 36 13/14 II 19 38 22 10 21 53 00 27 13/14 I 22 47 00 59 23 53 02 05 15 I 17 17 19 29 18 21 20 33 17 II 09 01 11 34 11 12 13 47 17 I 11 47 13 59 12 50 15 02 18/19 III 23 01 01 38 03 17 05 58 19 I 06 16 08 28 07 19 09 31 20/21 II 22 24 00 57 00 30 03 06 21 I 00 46 02 58 01 47 04 00 22 I 19 16 21 28 20 16 22 28 24 II 11 49 14 22 13 50 16 25 24 I 13 46 15 58 14 45 16 57 26 III 03 21 05 59 07 17 09 59 26 I 08 16 10 28 09 13 11 26 28 II 01 12 03 46 03 08 05 44 28 I 02 46 04 58 03 42 05 54 29/30 I 21 16 23 28 22 11 00 23 31 II 14 37 17 11 16 27 19 03 31 I 15 46 17 58 16 39 18 52

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78 Satellites of Jupiter BAA Handbook 2019

ECLIPSES, OCCULTATIONS AND TRANSITS

December Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 I 15 35 18 17

December Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 III 01 21 04 08 03 11 06 00

Jupiter in conjunction with the Sun: 2019 December 27d 18h

November Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 IV 01 15 01 51 2 III 07 41 10 22 11 16 13 59 2 I 10 16 12 28 11 08 13 20 4 II 04 01 06 36 05 46 08 22 4 I 04 46 06 58 05 36 07 49 5/ 6 I 23 16 01 28 00 05 02 18 7 II 17 26 20 01 19 05 21 42 7 I 17 46 19 58 18 34 20 47 9 III 12 04 14 46 15 15 17 59 9 I 12 16 14 28 13 02 15 15 11 I 06 46 08 59 07 31 09 44 11 II 06 50 09 26 08 23 11 00 13 I 01 16 03 29 02 00 04 13 14 I 19 46 21 59 20 28 22 41 14/15 II 20 16 22 52 21 43 00 20 16 I 14 16 16 29 14 57 17 10 16 III 16 28 19 12 19 13 21 59 17 IV 19 01 20 15 18 I 08 46 10 59 09 25 11 39 18 II 09 41 12 17 11 01 13 38 20 I 03 17 05 30 03 54 06 07 21/22 I 21 47 00 00 22 23 00 36 21/22 II 23 07 01 43 00 20 02 58 23 I 16 17 18 30 16 51 19 04 23/24 III 20 53 23 39 23 12 01 59 25 I 10 47 13 01 11 20 13 33 25 II 12 32 15 09 13 38 16 16 27 I 05 18 07 31 05 48 08 02 28/29 I 23 48 02 01 00 17 02 30 29 II 01 58 04 35 02 58 05 36 30 I 18 18 20 32 18 46 20 59

November Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 I 12 59 16 07 2 II 09 23 13 43 3 I 07 29 10 36 5 I 01 59 05 05 5/6 III 22 02 00 45 01 25 04 11 5/6 II 22 46 03 00 6 I 20 29 23 34 8 I 15 00 18 03 9 IV 11 54 12 58 9 II 12 09 16 18 10 I 09 30 12 31 12 I 04 00 07 00 13 II 01 33 05 35 13 III 02 26 05 11 05 25 08 11 13/14 I 22 31 01 29 15 I 17 01 19 58 16 II 14 56 18 53 17 I 11 32 14 27 19 I 06 02 08 55 20 II 04 20 08 10 20 III 06 53 12 13 21 I 00 32 03 24 22 I 19 03 21 53 23 II 17 44 21 27 24 I 13 33 16 22 26 IV 00 48 01 59 05 45 07 16 26 I 08 04 10 51 27 II 07 08 10 45 27 III 11 19 16 13 28 I 02 34 05 19 29 I 21 05 23 48 30/1 II 20 32 00 02

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BAA Handbook 2019 Saturn 79

SATURN Opposition: July 9 Conjunction: January 2

2019 Rings

RA Dec. Mag Equat Diam.

Polar Diam.

Major Axis

Minor Axis

DE Δ h m º ' " " " " º au

Jan. 7 18 52.4 –22 25 0.5 15.1 13.9 34.2 14.6 25.3 11.04017 18 57.4 –22 19 0.5 15.1 13.9 34.2 14.5 25.0 11.01427 19 2.3 –22 12 0.6 15.2 13.9 34.4 14.4 24.8 10.963

Feb. 6 19 7.0 –22 5 0.6 15.3 14.0 34.6 14.4 24.6 10.88716 19 11.5 –21 59 0.6 15.4 14.2 35.0 14.4 24.3 10.789

26 19 15.5 –21 52 0.6 15.6 14.3 35.3 14.4 24.1 10.671Mar. 8 19 19.1 –21 46 0.6 15.8 14.5 35.8 14.5 23.9 10.535

18 19 22.2 –21 40 0.6 16.0 14.7 36.3 14.6 23.7 10.38628 19 24.8 –21 35 0.6 16.3 14.9 36.9 14.8 23.6 10.227

Apr. 7 19 26.7 –21 32 0.6 16.5 15.2 37.5 14.9 23.5 10.061

17 19 27.9 –21 30 0.5 16.8 15.4 38.1 15.2 23.4 9.89527 19 28.5 –21 29 0.5 17.1 15.7 38.8 15.4 23.4 9.731

May 7 19 28.3 –21 30 0.4 17.4 15.9 39.4 15.6 23.4 9.57517 19 27.5 –21 32 0.4 17.6 16.2 40.0 15.9 23.5 9.43127 19 26.1 –21 35 0.3 17.9 16.4 40.5 16.2 23.6 9.305

Jun. 6 19 24.1 –21 40 0.2 18.1 16.6 41.0 16.5 23.7 9.19816 19 21.6 –21 46 0.2 18.2 16.7 41.4 16.7 23.9 9.11626 19 18.7 –21 52 0.1 18.3 16.9 41.6 17.0 24.0 9.061

Jul. 6 19 15.6 –21 58 0.1 18.4 16.9 41.7 17.1 24.2 9.03516 19 12.5 –22 5 0.1 18.4 16.9 41.7 17.2 24.4 9.038

26 19 9.4 –22 11 0.1 18.3 16.9 41.6 17.3 24.6 9.071Aug. 5 19 6.7 –22 16 0.2 18.2 16.7 41.3 17.3 24.8 9.133

15 19 4.2 –22 21 0.2 18.0 16.6 40.9 17.2 24.9 9.22025 19 2.3 –22 25 0.3 17.8 16.4 40.4 17.1 25.0 9.331

Sep. 4 19 1.0 –22 28 0.3 17.6 16.2 39.9 16.9 25.1 9.462

14 19 0.4 –22 30 0.4 17.3 15.9 39.3 16.7 25.2 9.60824 19 0.4 –22 31 0.4 17.0 15.7 38.6 16.4 25.2 9.766

Oct. 4 19 1.2 –22 31 0.5 16.7 15.4 38.0 16.1 25.1 9.93014 19 2.7 –22 30 0.5 16.5 15.2 37.4 15.8 25.1 10.09524 19 4.8 –22 27 0.5 16.2 14.9 36.8 15.5 25.0 10.258

Nov. 3 19 7.5 –22 24 0.6 16.0 14.7 36.2 15.2 24.9 10.41413 19 10.8 –22 19 0.6 15.7 14.5 35.7 14.9 24.7 10.55923 19 14.6 –22 14 0.6 15.5 14.3 35.3 14.6 24.5 10.688

Dec. 3 19 18.7 –22 7 0.6 15.4 14.1 34.9 14.4 24.3 10.79913 19 23.3 –21 59 0.6 15.3 14.0 34.6 14.1 24.0 10.890

23 19 28.0 –21 50 0.6 15.2 13.9 34.4 13.9 23.8 10.95733 19 33.0 –21 40 0.5 15.1 13.9 34.3 13.6 23.5 11.000

Description of the headings in the table can be found on page 22.

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80 Saturn BAA Handbook 2019

LONGITUDE OF CENTRAL MERIDIAN OF SATURNSYSTEM I

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 219.7 109.7 348.6 242.0 12.7 268.8 40.8 296.1 189.5 316.4 205.7 330.0 2 343.9 233.9 112.9 6.3 137.0 33.2 165.2 60.5 313.8 80.6 329.9 94.2 3 108.1 358.2 237.1 130.6 261.4 157.6 289.6 184.8 78.0 204.8 94.0 218.3 4 232.3 122.4 1.4 255.0 25.8 282.0 54.0 309.2 202.3 328.9 218.2 342.5 5 356.4 246.6 125.7 19.3 150.2 46.4 178.3 73.5 326.5 93.1 342.3 106.6 6 120.6 10.8 250.0 143.6 274.6 170.8 302.7 197.8 90.8 217.3 106.5 230.7 7 244.8 135.1 14.3 268.0 38.9 295.2 67.1 322.1 215.0 341.5 230.6 354.9 8 9.0 259.3 138.6 32.3 163.3 59.6 191.5 86.5 339.3 105.7 354.7 119.0 9 133.1 23.5 262.8 156.7 287.7 184.0 315.9 210.8 103.5 229.9 118.9 243.2 10 257.3 147.8 27.1 281.0 52.1 308.4 80.2 335.1 227.8 354.1 243.0 7.3 11 21.5 272.0 151.4 45.4 176.5 72.8 204.6 99.4 352.0 118.2 7.2 131.5 12 145.7 36.2 275.7 169.7 300.9 197.3 329.0 223.7 116.3 242.4 131.3 255.6 13 269.9 160.5 40.0 294.1 65.3 321.7 93.4 348.0 240.5 6.6 255.5 19.8 14 34.1 284.7 164.3 58.4 189.7 86.1 217.7 112.3 4.7 130.8 19.6 143.9 15 158.3 49.0 288.6 182.8 314.1 210.5 342.1 236.7 129.0 254.9 143.8 268.1 16 282.4 173.2 52.9 307.1 78.5 334.9 106.5 1.0 253.2 19.1 267.9 32.2 17 46.6 297.5 177.2 71.5 202.8 99.3 230.9 125.3 17.4 143.3 32.1 156.3 18 170.8 61.7 301.5 195.9 327.2 223.7 355.2 249.6 141.6 267.5 156.2 280.5 19 295.0 186.0 65.8 320.2 91.6 348.1 119.6 13.9 265.9 31.6 280.3 44.6 20 59.2 310.2 190.1 84.6 216.0 112.5 243.9 138.2 30.1 155.8 44.5 168.8 21 183.4 74.5 314.4 208.9 340.4 236.9 8.3 262.4 154.3 280.0 168.6 292.9 22 307.6 198.7 78.7 333.3 104.8 1.2 132.7 26.7 278.5 44.1 292.8 57.1 23 71.8 323.0 203.1 97.7 229.2 125.6 257.0 151.0 42.7 168.3 56.9 181.2 24 196.0 87.3 327.4 222.0 353.6 250.0 21.4 275.3 166.9 292.4 181.0 305.4 25 320.2 211.5 91.7 346.4 118.0 14.4 145.7 39.6 291.1 56.6 305.2 69.6 26 84.4 335.8 216.0 110.8 242.4 138.8 270.1 163.9 55.4 180.8 69.3 193.7 27 208.7 100.1 340.3 235.2 6.8 263.2 34.4 288.1 179.6 304.9 193.5 317.9 28 332.9 224.3 104.7 359.5 131.2 27.6 158.8 52.4 303.8 69.1 317.6 82.0 29 97.1 229.0 123.9 255.6 152.0 283.1 176.7 68.0 193.2 81.8 206.2 30 221.3 353.3 248.3 20.0 276.4 47.5 301.0 192.2 317.4 205.9 330.3 31 345.5 117.6 144.4 171.8 65.2 81.5 94.5

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 35.18 7 246.25 10 5.86 1 0.59 6 3.52 2 70.36 8 281.43 20 11.73 2 1.17 7 4.10 3 105.54 9 316.61 30 17.59 3 1.76 8 4.69 4 140.72 10 351.79 40 23.45 4 2.35 9 5.28 5 175.90 11 386.97 50 29.32 5 2.93 10 5.86 6 211.07 12 422.15 60 35.18

System I applies to all objects situated on or between the south component of the North Equatorial Belt and the north component of the South Equatorial Belt.

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BAA Handbook 2019 Saturn 81

LONGITUDE OF CENTRAL MERIDIAN OF SATURNSYSTEM II

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 234.3 203.0 257.4 229.4 111.0 85.7 328.7 302.7 274.8 152.8 120.9 356.3 2 326.2 294.9 349.3 321.4 203.0 177.8 60.8 34.8 6.8 244.7 212.8 88.2 3 58.0 26.8 81.3 53.4 295.1 269.9 152.8 126.8 98.8 336.6 304.6 180.0 4 149.9 118.7 173.3 145.5 27.2 2.0 244.9 218.8 190.7 68.5 36.5 271.9 5 241.8 210.6 265.3 237.5 119.3 94.1 337.0 310.9 282.7 160.4 128.3 3.7 6 333.7 302.6 357.2 329.5 211.3 186.2 69.1 42.9 14.6 252.3 220.2 95.6 7 65.5 34.5 89.2 61.6 303.4 278.3 161.2 134.9 106.6 344.2 312.0 187.4 8 157.4 126.4 181.2 153.6 35.5 10.4 253.3 227.0 198.6 76.1 43.9 279.3 9 249.3 218.4 273.2 245.6 127.6 102.5 345.3 319.0 290.5 167.9 135.7 11.1 10 341.2 310.3 5.2 337.7 219.7 194.6 77.4 51.0 22.4 259.8 227.6 102.9 11 73.1 42.2 97.2 69.7 311.8 286.8 169.5 143.0 114.4 351.7 319.4 194.8 12 164.9 134.2 189.2 161.8 43.8 18.9 261.6 235.0 206.3 83.6 51.3 286.6 13 256.8 226.1 281.1 253.8 135.9 111.0 353.7 327.0 298.3 175.5 143.1 18.5 14 348.7 318.0 13.1 345.9 228.0 203.1 85.7 59.1 30.2 267.3 235.0 110.3 15 80.6 50.0 105.1 77.9 320.1 295.2 177.8 151.1 122.1 359.2 326.8 202.2 16 172.5 141.9 197.1 170.0 52.2 27.3 269.9 243.1 214.1 91.1 58.7 294.0 17 264.4 233.9 289.1 262.0 144.3 119.3 1.9 335.1 306.0 183.0 150.5 25.9 18 356.3 325.8 21.1 354.1 236.4 211.4 94.0 67.1 37.9 274.8 242.4 117.7 19 88.2 57.8 113.1 86.1 328.5 303.5 186.1 159.1 129.9 6.7 334.2 209.6 20 180.1 149.7 205.1 178.2 60.6 35.6 278.1 251.1 221.8 98.6 66.1 301.4 21 272.0 241.7 297.2 270.3 152.7 127.7 10.2 343.1 313.7 190.5 157.9 33.3 22 3.9 333.6 29.2 2.3 244.8 219.8 102.3 75.1 45.6 282.3 249.8 125.1 23 95.8 65.6 121.2 94.4 336.9 311.9 194.3 167.1 137.5 14.2 341.6 217.0 24 187.7 157.5 213.2 186.5 69.0 44.0 286.4 259.0 229.5 106.1 73.4 308.8 25 279.6 249.5 305.2 278.5 161.1 136.1 18.4 351.0 321.4 197.9 165.3 40.7 26 11.5 341.5 37.2 10.6 253.2 228.2 110.5 83.0 53.3 289.8 257.1 132.6 27 103.4 73.4 129.2 102.7 345.2 320.3 202.5 175.0 145.2 21.6 349.0 224.4 28 195.3 165.4 221.3 194.7 77.3 52.4 294.6 267.0 237.1 113.5 80.8 316.3 29 287.2 313.3 286.8 169.4 144.5 26.6 358.9 329.0 205.4 172.7 48.1 30 19.1 45.3 18.9 261.5 236.6 118.7 90.9 60.9 297.2 264.5 140.0 31 111.0 137.3 353.6 210.7 182.9 29.1 231.8

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 33.83 7 236.83 10 5.64 1 0.56 6 3.38 2 67.67 8 270.67 20 11.28 2 1.13 7 3.95 3 101.50 9 304.50 30 16.92 3 1.69 8 4.51 4 135.33 10 338.33 40 22.56 4 2.26 9 5.08 5 169.17 11 372.17 50 28.19 5 2.82 10 5.64 6 203.00 12 406.00 60 33.83

System II applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt. However System III is used more often for these regions.

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82 Saturn BAA Handbook 2019

LONGITUDE OF CENTRAL MERIDIAN OF SATURNSYSTEM III

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 78.1 9.3 30.0 324.6 170.0 107.4 314.1 250.8 185.5 27.3 318.0 157.3 2 168.7 100.1 120.8 55.4 260.9 198.3 45.0 341.6 276.3 118.0 48.7 247.9 3 259.4 190.8 211.5 146.2 351.7 289.2 135.9 72.5 7.0 208.7 139.3 338.6 4 350.1 281.5 302.3 237.1 82.6 20.1 226.8 163.3 97.8 299.4 230.0 69.2 5 80.7 12.2 33.1 327.9 173.5 111.0 317.7 254.1 188.6 30.1 320.6 159.8 6 171.4 102.9 123.8 58.7 264.3 201.9 48.5 344.9 279.3 120.8 51.3 250.5 7 262.1 193.6 214.6 149.5 355.2 292.8 139.4 75.8 10.0 211.4 141.9 341.1 8 352.7 284.4 305.4 240.4 86.1 23.6 230.3 166.6 100.8 302.1 232.6 71.7 9 83.4 15.1 36.2 331.2 177.0 114.5 321.2 257.4 191.5 32.8 323.2 162.4 10 174.1 105.8 126.9 62.0 267.9 205.4 52.0 348.2 282.3 123.5 53.9 253.0 11 264.8 196.5 217.7 152.9 358.7 296.3 142.9 79.0 13.0 214.2 144.5 343.7 12 355.4 287.3 308.5 243.7 89.6 27.2 233.8 169.8 103.7 304.8 235.1 74.3 13 86.1 18.0 39.3 334.6 180.5 118.1 324.6 260.6 194.5 35.5 325.8 165.0 14 176.8 108.7 130.1 65.4 271.4 209.0 55.5 351.5 285.2 126.2 56.4 255.6 15 267.5 199.5 220.9 156.3 2.3 299.9 146.4 82.3 15.9 216.8 147.1 346.2 16 358.2 290.2 311.7 247.1 93.1 30.8 237.2 173.1 106.7 307.5 237.7 76.9 17 88.9 21.0 42.5 338.0 184.0 121.7 328.1 263.9 197.4 38.2 328.3 167.5 18 179.6 111.7 133.2 68.8 274.9 212.6 59.0 354.6 288.1 128.9 59.0 258.2 19 270.2 202.4 224.0 159.7 5.8 303.5 149.8 85.4 18.8 219.5 149.6 348.8 20 0.9 293.2 314.8 250.5 96.7 34.4 240.7 176.2 109.6 310.2 240.3 79.5 21 91.6 23.9 45.6 341.4 187.6 125.3 331.5 267.0 200.3 40.8 330.9 170.1 22 182.3 114.7 136.4 72.2 278.5 216.2 62.4 357.8 291.0 131.5 61.5 260.7 23 273.0 205.4 227.3 163.1 9.4 307.0 153.2 88.6 21.7 222.2 152.2 351.4 24 3.7 296.2 318.1 253.9 100.2 37.9 244.1 179.4 112.4 312.8 242.8 82.0 25 94.4 26.9 48.9 344.8 191.1 128.8 334.9 270.1 203.1 43.5 333.5 172.7 26 185.1 117.7 139.7 75.7 282.0 219.7 65.8 0.9 293.8 134.1 64.1 263.3 27 275.8 208.5 230.5 166.5 12.9 310.6 156.6 91.7 24.5 224.8 154.7 354.0 28 6.5 299.2 321.3 257.4 103.8 41.5 247.5 182.5 115.2 315.4 245.4 84.6 29 97.2 52.1 348.2 194.7 132.4 338.3 273.2 205.9 46.1 336.0 175.3 30 187.9 142.9 79.1 285.6 223.2 69.1 4.0 296.6 136.7 66.6 265.9 31 278.6 233.8 16.5 160.0 94.8 227.4 356.6

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 33.78 7 236.48 10 5.63 1 0.56 6 3.38 2 67.57 8 270.26 20 11.26 2 1.13 7 3.94 3 101.35 9 304.05 30 16.89 3 1.69 8 4.50 4 135.13 10 337.83 40 22.52 4 2.25 9 5.07 5 168.92 11 371.61 50 28.15 5 2.82 10 5.63 6 202.70 12 405.40 60 33.78

System III also applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt. This longitude system is based upon the rotation period of the planet’s magnetic field as defined by the International Astronomical Union.

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BAA Handbook 2019 Satellites of Saturn 83

SATELLITES OF SATURNMIMAS, ENCELADUS AND TETHYS

Mimas Enceladus Tethys Each fourth eastern elongation Each third eastern elongation Each second eastern elongation d h d h d h d h d h d h

Jan. 1 21.0 Jul. 5 14.35 15.5 9 8.79 10.0 13 3.2

13 4.5 16 21.616 23.0 20 16.120 17.5 24 10.524 12.0 28 5.028 6.5 31 23.5

Feb. 1 1.0 Aug. 4 17.94 19.5 8 12.48 14.0 12 6.8

12 8.5 16 1.316 3.0 19 19.719 21.5 23 14.223 16.0 27 8.727 10.5 31 3.1

Mar. 3 5.0 Sep. 3 21.66 23.5 7 16.1

10 18.0 11 10.614 12.5 15 5.018 7.0 18 23.522 1.4 22 18.025 19.9 26 12.529 14.4 30 7.0

Apr. 2 8.9 Oct. 4 1.56 3.4 7 20.09 21.8 11 14.4

13 16.3 15 8.917 10.8 19 3.421 5.2 22 21.924 23.7 26 16.428 18.2 30 10.9

May 2 12.6 Nov. 3 5.46 7.1 6 23.9

10 1.5 10 18.413 20.0 14 12.917 14.5 18 7.521 8.9 22 2.025 3.4 25 20.528 21.8 29 15.0

Jun. 1 16.3 Dec. 3 9.55 10.7 7 4.09 5.2 10 22.5

12 23.6 14 17.016 18.1 18 11.520 12.5 22 6.124 7.0 26 0.628 1.4 29 19.1

Jul. 1 19.9

Note: For intervening eastern elongations add: Mimas 0d 22.6h or 1d 21.2h or 2d 19.9h

Enceladus 1d 08.9h or 2d 17.8h

Tethys 1d 21.3h

Jan. 1 22.9 Jul. 5 22.76 1.6 10 1.3

10 4.3 14 4.014 7.0 18 6.618 9.7 22 9.222 12.4 26 11.926 15.1 30 14.530 17.8 Aug. 3 17.1

Feb. 3 20.5 7 19.77 23.2 11 22.4

12 1.9 16 1.016 4.6 20 3.720 7.3 24 6.324 10.0 28 9.028 12.7 Sep. 1 11.6

Mar. 4 15.3 5 14.38 18.0 9 16.9

12 20.7 13 19.616 23.4 17 22.221 2.0 22 0.925 4.7 26 3.629 7.4 30 6.2

Apr. 2 10.0 Oct. 4 8.96 12.7 8 11.6

10 15.4 12 14.314 18.0 16 17.018 20.7 20 19.622 23.3 24 22.327 2.0 29 1.0

May 1 4.6 Nov. 2 3.75 7.3 6 6.49 9.9 10 9.1

13 12.5 14 11.817 15.2 18 14.521 17.8 22 17.225 20.5 26 19.929 23.1 30 22.6

Jun. 3 1.7 Dec. 5 1.37 4.3 9 4.0

11 7.0 13 6.715 9.6 17 9.419 12.2 21 12.123 14.8 25 14.827 17.5 29 17.5

Jul. 1 20.1

Jan. 1 9.9 Jul. 5 10.55 4.5 9 5.18 23.2 12 23.6

12 17.9 16 18.216 12.6 20 12.820 7.2 24 7.424 1.9 28 2.027 20.6 31 20.531 15.2 Aug. 4 15.1

Feb. 4 9.9 8 9.78 4.6 12 4.3

11 23.2 15 22.915 17.9 19 17.519 12.5 23 12.123 7.2 27 6.727 1.8 31 1.3

Mar. 2 20.5 Sep. 3 19.96 15.1 7 14.5

10 9.8 11 9.114 4.4 15 3.717 23.1 18 22.421 17.7 22 17.025 12.3 26 11.629 7.0 30 6.3

Apr. 2 1.6 Oct. 4 0.95 20.2 7 19.59 14.9 11 14.2

13 9.5 15 8.817 4.1 19 3.520 22.7 22 22.124 17.3 26 16.828 11.9 30 11.4

May 2 6.5 Nov. 3 6.16 1.1 7 0.79 19.7 10 19.4

13 14.3 14 14.017 8.9 18 8.721 3.5 22 3.424 22.1 25 22.028 16.7 29 16.7

Jun. 1 11.3 Dec. 3 11.45 5.9 7 6.19 0.4 11 0.7

12 19.0 14 19.416 13.6 18 14.120 8.2 22 8.724 2.8 26 3.427 21.3 29 22.1

Jul. 1 15.9

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84 Satellites of Saturn BAA Handbook 2019

SATELLITES OF SATURNDIONE AND RHEA

Dione Rhea Each second eastern elongation Each second eastern elongation d h d h d h d h d h d h

---- -- ---- May 30 17.8 Sep. 17 04.2 Jan. 2 20.5 May 9 11.0 Sep. 12 20.6Feb. 15 17.3 Jun. 5 05.1 22 15.5 11 21.7 18 11.7 21 21.5 21 04.8 10 16.4 28 02.9 20 22.9 27 12.4 30 22.4 26 16.3 16 03.7 Oct. 3 14.3 30 00.1 Jun. 5 13.1 Oct. 9 23.3Mar. 4 03.7 21 15.0 9 01.8 Feb. 8 01.2 14 13.8 19 00.3 9 15.2 27 02.3 14 13.2 17 02.3 23 14.4 28 01.3 15 02.6 Jul. 2 13.6 20 00.6 26 03.4 Jul. 2 15.1 Nov. 6 02.4 20 14.0 8 00.9 25 12.1 Mar. 7 04.5 11 15.7 15 03.5 26 01.4 13 12.2 30 23.5 16 05.6 20 16.3 24 04.6 31 12.9 18 23.5 Nov. 5 11.0 25 06.6 29 16.9 Dec. 3 05.7Apr. 6 00.3 24 10.8 10 22.4 Apr. 3 07.5 Aug. 7 17.6 12 06.9 11 11.7 29 22.1 16 09.9 12 08.4 16 18.3 21 08.1 16 23.0 Aug. 4 09.4 21 21.4 21 09.3 25 19.0 30 09.2 22 10.4 9 20.7 27 08.9 30 10.2 Sep. 3 19.8 27 21.8 15 08.0 Dec. 2 20.4May 3 09.2 20 19.4 8 07.9 8 20.5 26 06.7 13 19.3 Note: For an intervening eastern elongation add: 14 07.8 31 18.1 19 06.8 19 19.2 Sep. 6 05.4 24 18.3 Dione 2d 17.7h

25 06.5 11 16.8 30 05.8 Rhea 4d 12.4h

TITAN AND HYPERION Titan Hyperion E. Elong. Inf. Conj’n W. Elong. Sup. Conj’n E.Elong. W Elong. d h d h d h d h d h d h

Jan. 8 07.7 Jan. 12 05.2 Jan. 16 09.5 20 12.2 Jan. 15 23.6 26 19.3 24 08.5 28 06.1 Feb. 1 10.4 Feb. 5 12.8 Feb. 6 07.9 Feb. 17 04.8Feb. 9 09.2 Feb. 13 06.7 17 11.0 21 13.2 27 16.3 Mar. 10 14.1 25 09.7 Mar. 1 07.2 Mar. 5 11.4 Mar. 9 13.4 Mar. 21 00.5 31 23.0Mar. 13 09.8 17 07.3 21 11.4 25 13.2 Apr. 11 08.5 Apr. 22 07.2 29 09.6 Apr. 2 07.0 Apr. 6 11.0 Apr. 10 12.6 May 2 16.0 May 13 14.7Apr. 14 08.9 18 06.2 22 10.2 26 11.5 23 23.0 Jun. 3 21.4 30 07.8 May 4 05.0 May 8 08.8 May 12 10.1 Jun. 14 05.6 25 03.6May 16 06.2 20 03.3 24 06.9 28 08.2 Jul. 5 12.1 Jul. 16 09.8Jun. 1 04.1 Jun. 5 01.2 Jun. 9 04.7 Jun. 13 06.0 26 18.8 Aug. 6 16.3 17 01.8 20 22.7 25 02.1 29 03.5 Aug. 17 02.0 27 23.8Jul. 2 23.1 Jul. 6 20.1 Jul. 10 23.3 Jul. 15 01.0 Sep. 7 10.2 Sep. 18 08.5 18 20.5 22 17.4 26 20.6 30 22.5 28 19.4 Oct. 9 18.5Aug. 3 17.9 Aug. 7 14.9 Aug. 11 18.1 Aug. 15 20.2 Oct. 20 05.5 31 05.6 19 15.6 23 12.7 27 15.9 31 18.3 Nov. 10 16.4 Nov. 21 17.5Sep. 4 13.6 Sep. 8 10.9 Sep. 12 14.2 Sep. 16 16.7 Dec. 2 03.6 Dec. 13 05.8 20 12.2 24 09.6 28 13.0 Oct. 2 15.7 23 14.9 Oct. 6 11.2 Oct. 10 08.8 Oct. 14 12.3 18 15.0 22 10.7 26 08.4 30 12.0 Nov. 3 14.8 Nov. 7 10.6 Nov. 11 08.5 Nov. 15 12.2 19 15.0 23 10.9 27 08.9 Dec. 1 12.7 Dec. 5 15.4 Dec. 9 11.5 Dec. 13 09.6 17 13.5 21 15.9 25 12.2 29 10.4

Position-angle and angular-distances can be obtained from JPL’s Horizons web page at:http://ssd.jpl.nasa.gov/?horizons

(see page 114)

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BAA Handbook 2019 Satellites of Saturn 85

TITAN

Saturn is not in conjunction with Sun during 2018.

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86 Satellites of Saturn BAA Handbook 2019

IAPETUSIapetus shows variations in brightness, and is always brighter at western elongation than at eastern. The diagrams show the apparent path of Iapetus relative to Saturn, the units being in seconds of arc. Conjunction of Saturn is indicated by the faint portion of the orbit path from Jan.1 to Feb.2 and from Dec.15 to Dec.31. E. Elong. Inf. Conj’n. W. Elong. Sup. Conj’n. d h d h d h d h

Mar. 19 16.3 Apr. 7 19.3 Apr. 28 18.1 May 18 21.7 Jun. 6 23.5 Jun. 25 17.2 Jul. 15 22.2 Aug. 5 05.0 Aug. 23 22.3 Sep. 12 03.3 Oct. 2 09.8 Oct. 23 11.3 Nov. 11 15.3 Dec. 1 09.1 Dec. 22 08.0

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BAA Handbook 2019 Uranus 87

URANUSUranus is at opposition on October 28, magnitude 5.7, diameter 3.7"

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88 Neptune BAA Handbook 2019

NEPTUNENeptune is at opposition on September 10, magnitude 7.8, diameter 2.4"

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BAA Handbook 2019 Trans-Neptunian Objects 89

Trans–Neptunian & Scattered–Disk Objects

The list comprises the date, magnitude, geocentric position and apparent motion when at opposition in 2019, of the 24 most intrinsically bright objects known as of 2018 June 11. The sizes of the smaller objects listed are often speculative given that they are based on an estimated albedo only. If you wish to observe an object then go to the website of the Minor Planet and Comet Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Here you enter the date and the designation of the object(s) you wish to observe. Given the extreme distance of these objects, the geocentric position will be sufficiently accurate for any location on the Earth.

Object Opposition Approx. MotionNumber/Name Prov ID Date V H Diam. Δ RA Dec. Speed P km au h m º ' "/min º

(136199) Eris 2003 UB313 Oct. 17 18.7 –1.1 2326 95.05 1 44.5 –1 57.3 0.025 252(134340) Pluto Jul. 14 14.5 –0.8 2374 32.58 19 33.7 –22 07.0 0.061 257(136472) Makemake 2005 FY9 Mar. 25 17.1 –0.2 1450 51.67 13 05.1 +24 20.5 0.042 296(136108) Haumea 2003 EL61 Apr. 16 17.3 0.2 1500* 49.54 14 16.6 +16 47.0 0.043 293(90377) Sedna 2003 VB12 Nov. 20 20.8 1.5 1030 83.69 3 50.7 +7 46.7 0.026 258(225088) 2007 OR10 Aug. 27 21.3 1.8 1350 87.29 22 25.1 –11 56.7 0.026 251(90482) Orcus 2004 DW Mar. 1 19.1 2.2 940 47.14 10 15.7 –10 39.6 0.046 291(50000) Quaoar 2002 LM60 Jun. 24 18.7 2.4 890 41.85 18 08.6 –15 17.9 0.049 269 2013 FY27 Mar. 7 22.1 3.0 900 79.00 10 47.5 –6 48.4 0.029 295(174567) Varda 2003 MW12 Jun. 12 19.9 3.2 700 45.63 17 26.8 –1 43.3 0.045 275(55565) 2002 AW197 Feb. 20 19.9 3.3 730 44.40 9 52.6 –2 28.1 0.048 287(229762) 2007 UK126 Dec. 5 19.6 3.3 610 40.94 4 56.6 +1 53.5 0.051 266(55636) 2002 TX300 Oct. 28 19.8 3.4 300 41.81 1 27.4 +36 13.6 0.050 247 2014 UZ224 Nov. 6 23.1 3.5 635 89.29 3 14.3 –10 07.5 0.025 253(202421) 2005 UQ513 Oct. 19 20.4 3.5 500 47.06 0 52.2 +33 42.8 0.045 245(303775) 2005 QU182 Oct. 13 20.9 3.6 420 52.38 1 31.5 –3 38.0 0.040 249(307261) 2002 MS4 Jul. 4 20.3 3.6 930 45.62 18 45.7 –6 23.8 0.046 267(208996) 2003 AZ84 Jan. 25 20.1 3.6 700 43.49 8 16.7 +8 21.7 0.050 282(28978) Ixion 2001 KX76 Jun. 19 19.5 3.6 650 38.21 17 48.3 –29 19.2 0.054 268(55637) 2002 UX25 Nov. 8 19.7 3.6 665 39.36 3 01.7 +9 25.9 0.054 250(20000) Varuna 2000 WR106 Jan. 22 20.0 3.6 700 42.95 8 22.3 +27 01.2 0.050 286 2014 EZ51 May 21 21.1 3.7 660 54.50 15 45.3 –25 36.8 0.039 281 2015 RR245 Oct. 2 21.7 3.7 670 61.51 0 28.1 +6 17.4 0.035 246(145452) 2005 RN43 Sep. 8 19.8 3.7 680 39.61 22 55.2 +1 11.4 0.052 244

*Haumea is asymmetric in shape being roughly 1940km x 1530km x 993km in size.

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90 Dwarf Planets BAA Handbook 2019

Pluto is at opposition, in Sagittarius, on July 14 at magnitude 14.2.Its brightness varies little during the year, ranging in visual magnitude from 14.2 to 14.4.Charts prepared using GUIDE 8.0. Stars down to magnitude 12.0 are shown.

DWARF PLANETS(134340) Pluto

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BAA Handbook 2019 Dwarf Planets 91

DWARF PLANETS(134340) Pluto

Detailed charts around the time of opposition. Jun. 14 to Jul. 14 Jul. 14 to Aug. 14

The charts show stars down to magnitude 14.

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92 Dwarf Planets BAA Handbook 2019

DWARF PLANETSDWARF PLANETSORBITAL ELEMENTS

The geocentric data below have been extracted from the Minor Planet Center Ephemeris Service at: http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox J2000, Epoch of the elements, JD 2458200.5, 2018 Mar. 23.0 TT No. Name a e i Node Peri. M au ° ° ° ° 1 Ceres 2.767 0.076 10.594 80.310 73.115 352.231 134340 Pluto 39.767 0.254 17.119 110.297 114.499 40.367 136108 Haumea 43.346 0.190 28.206 122.018 238.694 214.976 136199 Eris 67.668 0.441 44.200 35.880 151.599 205.019 136472 Makemake 45.672 0.156 28.984 79.617 295.631 162.052More information on asteroids and dwarf planets can be found on the website of the Asteroids and Remote Planets Section at: http://www.britastro.org/asteroids/

EPHEMERIDESThe data below have been extracted from the Minor Planet Center Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox J2000, Epoch of the elements, JD 2458200.5, 2018 Mar. 23.0 TT

1 Ceres2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 15 20 06.7 –11 46 28 3.182 2.652 49.6 8.9 11 15 35 00.5 –12 44 20 3.082 2.659 55.9 8.9 21 15 49 14.5 –13 34 33 2.974 2.666 62.4 8.8 31 16 02 38.9 –14 17 21 2.859 2.673 69.2 8.8Feb. 10 16 15 01.4 –14 53 04 2.738 2.680 76.2 8.7 20 16 26 07.8 –15 22 17 2.613 2.688 83.6 8.7Mar. 2 16 35 44.0 –15 45 50 2.486 2.695 91.2 8.6 12 16 43 32.5 –16 04 37 2.359 2.703 99.3 8.4 22 16 49 16.1 –16 19 43 2.235 2.711 107.8 8.3Apr. 1 16 52 38.8 –16 32 18 2.118 2.718 116.8 8.2 11 16 53 25.1 –16 43 26 2.010 2.726 126.4 8.0 21 16 51 27.9 –16 54 06 1.916 2.734 136.5 7.8May 1 16 46 50.5 –17 04 59 1.840 2.742 147.2 7.6 11 16 39 50.7 –17 16 28 1.785 2.750 158.4 7.4 21 16 31 07.7 –17 28 55 1.756 2.758 169.7 7.1 31 16 21 34.8 –17 42 38 1.754 2.765 175.5 7.0Jun. 10 16 12 14.1 –17 58 15 1.779 2.773 165.5 7.3 20 16 04 05.9 –18 16 43 1.830 2.781 154.3 7.5 30 15 57 54.0 –18 38 53 1.905 2.789 143.5 7.7Jul. 10 15 54 06.3 –19 05 25 2.001 2.797 133.2 8.0 20 15 52 53.6 –19 36 33 2.113 2.804 123.5 8.2 30 15 54 12.7 –20 11 53 2.237 2.812 114.4 8.3Aug. 9 15 57 55.2 –20 50 45 2.370 2.820 105.8 8.5 19 16 03 47.6 –21 32 08 2.508 2.827 97.7 8.7 29 16 11 35.4 –22 14 52 2.650 2.835 89.9 8.8

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BAA Handbook 2019 Dwarf Planets 93

DWARF PLANETS134340 Pluto

2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° May 1 19 38 59.6 –21 47 21 33.478 33.790 107.2 14.7 21 19 38 21.3 –21 50 56 33.189 33.803 126.7 14.7Jun. 10 19 37 01.7 –21 56 05 32.968 33.816 146.2 14.6 30 19 35 12.9 –22 02 16 32.843 33.829 165.7 14.6Jul. 20 19 33 10.8 –22 08 46 32.830 33.842 174.7 14.5 Aug. 9 19 31 13.5 –22 14 54 32.933 33.855 155.1 14.6 29 19 29 38.4 –22 20 03 33.140 33.868 135.5 14.7Sep. 18 19 28 40.1 –22 23 46 33.431 33.882 115.9 14.7Oct. 8 19 28 28.2 –22 25 45 33.772 33.895 96.2 14.8 28 19 29 06.8 –22 25 56 34.126 33.908 76.5 14.8

136108 Haumea2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 21 14 19 15.3 +15 58 06 50.373 50.440 93.4 17.4Feb. 10 14 19 22.4 +16 09 19 50.071 50.436 111.2 17.4Mar. 2 14 18 57.8 +16 21 59 49.814 50.432 128.1 17.3 22 14 18 05.8 +16 34 22 49.631 50.427 142.7 17.3Apr. 11 14 16 54.4 +16 44 49 49.544 50.423 151.0 17.3 May 1 14 15 33.9 +16 51 57 49.560 50.418 148.1 17.3 21 14 14 15.6 +16 54 50 49.677 50.414 136.4 17.3Jun. 10 14 13 10.3 +16 53 07 49.877 50.409 121.1 17.4 30 14 12 26.6 +16 46 59 50.137 50.405 104.7 17.4Jul. 20 14 12 10.4 +16 37 09 50.426 50.401 88.0 17.4

136199 Eris2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jun. 30 1 46 15.2 –1 40 33 96.322 96.047 74.0 18.8Jul. 20 1 46 25.7 –1 41 28 95.991 96.043 92.6 18.8Aug. 9 1 46 21.0 –1 43 50 95.665 96.039 111.4 18.8 29 1 46 01.6 –1 47 18 95.381 96.035 130.1 18.8Sep. 18 1 45 29.6 –1 51 24 95.171 96.031 148.6 18.8 Oct. 8 1 44 48.8 –1 55 33 95.062 96.027 164.9 18.7 28 1 44 04.1 –1 59 10 95.067 96.023 164.1 18.8Nov. 17 1 43 21.2 –2 01 40 95.187 96.019 147.2 18.8Dec. 7 1 42 45.5 –2 02 38 95.408 96.015 127.8 18.8 27 1 42 21.8 –2 01 51 95.704 96.011 107.9 18.8

136472 Makemake2019 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 13 07 43.1 +23 33 23 52.464 52.540 93.9 17.2 21 13 07 50.8 +23 43 45 52.170 52.541 111.7 17.1Feb. 10 13 07 26.9 +23 55 56 51.921 52.543 128.7 17.1Mar. 2 13 06 35.4 +24 08 11 51.748 52.545 143.2 17.1 22 13 05 24.0 +24 18 46 51.672 52.546 151.1 17.1 Apr. 11 13 04 03.1 +24 26 10 51.701 52.548 147.4 17.1May 1 13 02 44.0 +24 29 21 51.830 52.550 135.2 17.1 21 13 01 37.5 +24 27 51 52.043 52.552 119.7 17.1Jun. 10 13 00 52.4 +24 21 50 52.312 52.553 103.2 17.2 30 13 00 34.5 +24 11 54 52.609 52.555 86.4 17.2

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94 Comets BAA Handbook 2019

The date of perihelion (T), period (P), perihelion distance (q) and the magnitude parameters H and G are given for each comet which comes to perihelion in 2019 [and which becomes brighter than 19th magnitude] and for other comets which are expected to be brighter than 14th magnitude during 2019. The table also gives the date that the comet is expected to be at its brightest, its declination, elongation and expected peak magnitude.

The magnitude parameters are taken from determinations by the Comet Section (rows highlighted in red), or from the elements downloaded from the MPC. The predicted total magnitude is given by: m1 = H + 2.5 G (log10 r) + 5 (log10 Δ)

where Δ is the distance of the comet from Earth and r is its distance from the Sun, both in Astronomical Units. Note that comets which show bright magnitudes at very small elongations (e.g P/2008 Y12 (SOHO)) are unlikely to be observable. The table is derived from orbital elements downloaded from the Minor Planet Center (MPC) on 2018 June 22 and it is sorted in order of the date at which the comet reaches its brightest magnitude. A digital version containing more information is available from the Comet Section website at https://britastro.org/comet. This website contains links to many other resources useful to the comet observer, in particular the Comet Section observing guide which is available for download as a PDF. There are no particularly bright comets predicted for 2019 but charts are provided for three potentially interesting objects:29P/Schwassmann-Wachmann is a comet in a nearly circular orbit with a period of 14.8 years. In 2019 it comes to opposition on 2019 October 9 and it is now north of the celestial equator which makes it easier to observe from northern latitudes. It spends most of the time at around 16th magnitude but has frequent outbursts. It should be kept under observation as regularly as possible.

Analysis by Richard Miles (Miles, R., Icarus 272, 387-413 (2016)) has shown that brighter outbursts occur at three zones in the rotation of the comet’s nucleus corresponding to the following ranges of rotational phase: 0.19 – 0.32, 0.45 – 0.52 and 0.75 – 0.96 although seasonal activity in 2019 is expected to be below average. The rotation phase at Julian Date T is defined as (T-2455229.98)/57.710. The comet’s elongation is less than 30° between February and April.

Rotation Number

Zone 1 Zone 2 Zone 3

Start End Start End Start End

56 - - Jan. 4 Jan. 9 Jan. 21 Feb. 2

57 - - - - - -

58 - - Apr. 29 May 3 May 16 May 29

59 Jun. 11 Jun. 18 Jun. 26 Jun. 30 Jul. 13 Jul. 25

60 Aug. 8 Aug. 15 Aug. 23 Aug. 27 Sep. 9 Sep. 21

61 Oct. 4 Oct. 12 Oct. 19 Oct. 23 Nov. 6 Nov. 18

62 Dec. 1 Dec. 8 Dec. 16 Dec. 20 - -

289P/Blanpain was originally discovered in 1819 as a 8th magnitude object, but it was then lost until its recovery as a faint asteroidal object by the Catalina survey in 2003. It is likely that it was in outburst at the time of its original discovery and it is an intrinsically faint object that shows little activity. Its best returns occur if it reaches perihelion in late December, as it does in 2019, however its peak magnitude is extremely uncertain and depends on the level of cometary activity. It is worth keeping under observation in the latter part of 2019 in case anything unusual happens.

C/2017 T2 (PANSTARRS) was discovered as a 20th magnitude object on 2017 October 2 and it comes to perihelion in 2020 May when it may reach 8th magnitude. It spends 2019 gradually moving northwards starting the year at around 16th magnitude and ending at around 10.

COMETS

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BAA Handbook 2019 Comets 95

COMETSName T q P H G Date of Dec. Elong. Peak

peak at peak Magnitude yyyy- mm- dd au years dd ° °C/2016 N6 (PANSTARRS) 2018-07-18 2.67 7.0 4.0 Jan. 1 –18.3 138 13.9C/2016 M1 (PANSTARRS) 2018-08-10 2.21 5.7 3.4 1 –86.2 64 11.948P/Johnson 2018-08-12 2.00 6.54 7.0 4.9 1 –12.9 –76 13.221P/Giacobini–Zinner 2018-09-10 1.01 6.54 5.4 12.3 1 –37.2 –120 13.364P/Swift–Gehrels 2018-11-03 1.39 9.41 9.0 8.0 1 29.9 –129 12.238P/Stephan–Oterma 2018-11-10 1.59 37.93 3.5 12.0 1 40.8 151 10.046P/Wirtanen 2018-12-12 1.06 5.43 8.2 6.4 1 57.3 –146 4.2P/2007 V1 (Larson) 2019-01-12 2.68 11.10 12.0 4.0 1 23.5 –116 17.9171P/Spahr 2019-01-13 1.77 6.71 10.2 6.0 1 7.1 –143 13.7131P/Mueller 2019-01-24 2.42 7.06 11.0 4.0 1 2.0 –83 16.7223P/Skiff 2019-01-27 2.43 8.48 12.0 4.0 1 7.7 –71 17.9P/1996 R2 (Lagerkvist) 2019-02-11 2.59 7.33 11.5 4.0 1 –8.2 –63 18.0232P/Hill 2019-04-06 2.98 9.51 11.5 4.0 1 34.6 –159 17.9P/2011 W2 (Rinner) 2019-04-09 2.31 7.43 13.0 4.0 1 12.1 –121 18.1C/2018 A3 (ATLAS) 2019-01-12 3.28 8.5 4.0 10 74.4 126 15.031P/Schwassmann–Wach. 2019-07-06 3.43 8.75 6.7 4.5 10 21.8 –171 14.9C/2016 X1 (Lemmon) 2019-04-29 7.56 6.0 4.0 16 4.0 –161 18.9239P/LINEAR 2019-01-10 1.65 9.45 17.5 2.0 17 0.5 159 17.860P/Tsuchinshan 2018-12-11 1.62 6.58 10.5 6.0 26 –4.9 127 13.7C/2010 U3 (Boattini) 2019-02-26 8.45 1.0 4.0 29 73.4 –119 14.8123P/West–Hartley 2019-02-05 2.13 7.58 4.0 10.0 Feb. 21 31.8 152 12.6231P/LINEAR–NEAT 2019-06-13 3.02 8.06 14.5 2.0 27 17.1 –171 18.578P/Gehrels 2019-04-02 2.01 7.23 –2.7 16.3 Mar. 23 9.7 –25 12.0149P/Mueller 2019-02-16 2.63 8.97 8.0 8.0 26 24.8 140 17.7P/2014 C1 (TOTAS) 2019-04-13 1.68 5.31 15.5 4.0 30 2.5 –169 17.0264P/Larsen 2019-08-04 2.44 7.69 13.0 4.0 Apr. 3 –19.5 –139 18.3C/2018 A6 (Gibbs) 2019-07-14 3.02 60.11 9.0 4.0 16 –57.0 –99 16.2P/2005 GF8 (LONEOS) 2019-09-30 2.83 14.17 11.5 4.0 May 4 –7.3 –152 17.9C/2017 M4 (ATLAS) 2019-01-18 3.25 6.0 4.0 5 –37.9 149 13.3222P/LINEAR 2019-06-04 0.83 4.94 16.5 6.0 31 11.1 37 16.0186P/Garradd 2019-05-05 4.39 11.19 7.5 4.0 Jun. 9 –57.0 –146 16.7209P/LINEAR 2019-06-12 0.97 5.10 17.0 2.0 Jul. 1 6.6 –69 16.2P/2012 K3 (Gibbs) 2019-08-17 2.09 6.90 15.0 4.0 15 –14.2 –165 18.4P/2006 H1 (McNaught) 2019-12-08 2.42 13.85 12.5 4.0 19 –39.8 –131 18.2C/2017 B3 (LINEAR) 2019-02-02 3.92 6.0 4.0 24 –45.7 123 15.0215P/NEAT 2019-11-12 3.61 9.08 11.0 4.0 27 –33.1 –166 18.7160P/LINEAR 2019-12-02 1.78 7.33 15.0 2.0 Aug. 13 –39.9 –133 17.0168P/Hergenrother 2019-08-05 1.36 6.79 10.3 2.7 23 34.3 80 11.5322P/SOHO 2019-08-31 0.05 3.98 22.1 5.1 31 10.2 2 5.6P/1999 R1 (SOHO) 2019-08-31 0.05 3.98 27.0 6.0 31 10.2 3 7.6P/2007 T4 (Gibbs) 2019-07-23 2.00 12.02 13.0 4.0 Sep. 4 36.5 46 18.2P/2008 Y1 (Boattini) 2019-09-10 1.27 10.53 15.0 4.0 14 24.0 61 16.8260P/McNaught 2019-09-09 1.42 6.91 13.5 4.0 25 35.7 128 13.868P/Klemola 2019-11-09 1.79 11.00 6.8 6.0 27 –13.4 –90 11.7P/2014 U2 (Kowalski) 2019-10-11 1.12 4.96 19.5 4.0 Oct. 1 35.7 109 17.329P/Schwassmann–Wach. 2019-03-09 5.77 14.78 4.0 4.0 8 15.5 170 15.0P/2008 Y12 (SOHO) 2019-10-09 0.07 5.40 9.0 4.0 10 –4.3 4 –2.6200P/Larsen 2019-07-28 3.30 10.95 9.0 4.0 12 18.4 168 16.1261P/Larson 2019-06-18 2.01 6.52 14.0 4.0 16 29.3 140 18.1P/2010 U2 (Hill) 2019-09-15 2.57 8.87 13.0 4.0 Nov. 11 42.9 154 18.376P/W.Kohoutek–Ikemura 2019-10-26 1.60 6.47 8.0 12.0 20 27.4 103 14.5294P/LINEAR 2019-11-29 1.30 5.74 15.5 4.0 Dec. 4 –23.4 36 18.1114P/Wiseman–Skiff 2019-01-14 1.58 6.68 11.5 6.0 18 31.2 –136 13.9155P/Shoemaker 2019-11-15 1.80 16.90 10.0 4.8 31 11.7 114 13.7289P/Blanpain 2019-12-21 0.96 5.32 10.0 4.0 31 16.6 –81 5.3C/2017 T2 (PANSTARRS) 2020-05-04 1.61 5.0 4.0 31 55.1 –133 9.5246P/NEAT 2021-02-22 2.87 8.06 2.5 6.0 31 11.6 90 13.4

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96 Comets BAA Handbook 2019

CO

ME

TS

Jun

30, 2

018

7:1

1 U

170

Peg

1h 2

0m0h

40m

0h 0

0m23

h 20

m22

h 40

m

+20°

+15°

+10°

+ 5°

+ 0° - 5°

Jan

1 0

:00

UT

Jan

21

Feb

10

Mar

2

Mar

22

Apr

11

May

1

May

21

Jun

10

Jun

30

Jul

20

Aug

9 Aug

29

Sep

18

Oct

8

Oct

28 N

ov 1

7 D

ec 7

0:0

0 U

T

Peg

asus

Pisc

es

29P/

SCH

WA

SSM

AN

N-W

AC

HM

AN

N

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BAA Handbook 2019 Comets 97

COMETS

Jun 30, 2018 7:04 U259 Psc

0h 40m 0h 00m 23h 20m 22h 40m

+30°

+20°

+10°

+ 0°

-10°

-20°

Nov 1 0:00 UT Nov 6 Nov 11 Nov 16

Nov 21

Nov 26

Dec 1

Dec 6

Dec 11

Dec 16

Dec 21

Dec 26

Dec 31

Jan 5 0:00 UT

Aquarius

Pegasus

Pisces

289P/BLANPAIN

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98 Comets BAA Handbook 2019

COMETS

Jun 30, 2018 7:00 U95 Tau

5h 00m 4h 00m 3h 00m

+50°

+40°

+30°

+20°

+10°

+ 0°

Jul 1 0:00 UT Jul 11

Jul 21 Jul 31

Aug 10 Aug 20

Aug 30

Sep 9

Sep 19

Sep 29

Oct 9

Oct 19

Oct 29

Nov 8

Nov 18

Nov 28

Dec 8

Dec 18

Dec 28

Jan 7 0:00 UT

Aries

Perseus

Taurus

C/2017 T2 (PANSTARRS)

Page 101: The British Astronomical Association Handbook 2019 · Welcome to the 98th Handbook of the British Astronomical Association. The Handbook highlights forthcoming astronomical events

BAA Handbook 2019 Meteor Diary 99

METEORSThis meteor diary has been considerably modified from that published in previous years to more closely follow the list of regular major and more reliable minor showers in the List of Established Meteor Showers published by the IAU Meteor Data Center (MDC).

The data for many showers are derived from the Cameras for Allsky Meteor Surveillance project (CAMS) published by Jenniskens et al., 2016, Icarus, 266, 331. Due to space constraints in the Handbook this list does not include any minor showers where the peak Zenithal Hourly Rate (ZHR) is less than 5 meteors per hour. A number of the far southern hemisphere showers have also been excluded. Radiant data (UT, Alt.) and twilight data are for observers at the standard latitudes 52°N and 35°S, on the Greenwich meridian. Moonrise and moonset may be determined from the data on pages 29-33. All times are in UT. Normal limits are the dates between which the shower rates are normally greater than 25 per cent of the sporadic rate for the period.

Zenithal Hourly Rate (ZHR) is the probable hourly rate for a single experienced observer watching a clear sky with limiting magnitude 6.5 with the shower radiant at the zenith. To a first approximation, the observed hourly rate (OHR) is given by:

OHR = ZHR sin α

where α is the radiant elevation. Hence high rates cannot be expected if the radiant is low. Sky conditions can alter rates considerably and consequently observers should record the approximate naked eye limiting magnitude in the areas being watched during each observing session. The rates given are the maximum ones, and are only a guide in view of the inherent variability of showers.

Twilight here is nautical, starting and ending when the Sun is 12° below the horizon.

Radiant Daily Motion: Where available, these come from the IAU's List of Established Meteor Showers. Meteor radiants are not stationary because of the Earth’s motion around the Sun. They move about one degree of ecliptic longitude per day. The daily motions should be applied to determine the radiant positions at dates other than maximum. The positions of several shower radiants at maximum, radiant daily motion and geocentric velocities (Vg) have been revised following analysis of recent video meteor data by Alex Pratt using the NEMETODE multi-station video meteor dataset..

Special Notes for 2019:Bright moonlight has an adverse effect on meteor observing, and for about five days to either side of Full Moon, lunar glare swamps all but the brighter meteors. Unfortunately, in 2019 observations of many of the major showers will be hampered by moonlight. The April Lyrids will be affected by a waning gibbous Moon in Scorpius, the Perseids by a near Full Moon in Sagittarius, the Draconids by a waxing gibbous Moon in Capricornus, the Orionids by a last quarter Moon in Gemini and Cancer, the Northern Taurids by a Full Moon in Taurus, the Leonids by a last quarter Moon in Cancer and watches for the Geminids will be seriously hindered by a virtually Full Moon in Gemini. Visual observers may, however, minimize the effects of moonlight by positioning themselves so the Moon is behind them and hidden behind a wall or other suitable obstruction. This is easiest when the Moon is fairly low in the southern sky as it will be for the Lyrids, Perseids and Draconids.

There are, however, many excellent observing opportunities in 2019. The Quadrantids coincide with New Moon and peak in the early morning hours with the radiant well placed in the north-eastern sky. The complex of minor showers which peak in late July, now grouped together as part of the Antihelion Source, and the Alpha Capricornids, Southern Delta Aquarids and Piscis Austrinids are all well placed with respect to the Moon this year. The Southern Taurids which peak in early November should also be largely unaffected. The Ursids in late December are also very favourable in 2019 and are a shower badly in need of observation. This is also a year when many of the minor showers will be observable in dark skies offering a chance to monitor some of the less well studied streams, many of which have displayed unexpected outbursts in the past. Such showers include the June Bootids, Alpha Aurigids, October Camelopardalids and Alpha Monocerotids.

It is hoped that observers will make a particular effort to take advantage of all observing opportunities throughout 2019. As always, observations away from the major shower maxima and of year-round sporadic activity are every bit as important to the work of the Association’s Meteor Section as those obtained when high rates are anticipated.

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100 Meteor Diary BAA Handbook 2019

METEORS METEORSShower Maximum Radiant Position Latitude 52°N Latitude 35°S

Notes

Maximum Daily Motion Twilight Radiant Twilight Radiant

NameNormal

Limits of Activity

λ☉ (2000.0)

°Date ZHR

at Max.R.A. Dec. R.A. Dec. Vg Local Time

of Transit DateAge of Moon Ends Begins UT Alt. Ends Begins UT Alt.

hh:mm (°) ° ° ° km/s h d h h h ° h h h °Quadrantids Dec. 28

-Jan. 12283.2 Jan. 4d 03h 80+ 15:18 (229) +49.5 +0.34 –0.25 40.7 8.5 Jan. 4 28 17.4 6.7 00

0306

214167

- - - - High activity, but with a rather narrow peak. Good in 2014. Bright events leave persistent trains. Very favourable.

April Lyrids Apr. 14-30

032.0 Apr. 22d 16h 15 18:07 (272) +33.1 +0.84 –0.34 47.3 4.1 Apr. 22 17 20.6 3.4 210003

174368

18.4 5.6 010305

092021

Normally rather moderate activity, but fine displays in 1803, 1922, 1982. Unfavourable.

η Aquarids Apr. 19-May 28

046 May 6-7 40 22:32 (338) –0.8 +0.92 +0.37 65.7 7.7 May 7 3 21.1 2.8 0203

9312

18.2 5.7 020406

052948

Fine southern shower, poorly seen from the UK. Fast meteors, many with persistent trains. Good in 2013.

Daytime Arietids May 22 – Jul. 2

077 Jun. 8 30? 02:56 (044) +24 +1.05 +0.28 41.1 9.9 Jun. 8 - - - 030915

116026

- - 061014

103106

Most active of the daytime showers. Good for radio observers. ZHR and radiant location uncertain.

June Bootids Jun. 22 - Jul. 2

096 Jun. 28 ? 14:52 (223) +48 ? ? 14.1 20.7 Jun. 28 26 22.5 1.6 220002

745640

- - - - Unexpected outburst with ZHR~100 m/h in 1998 June 27 after a quiescent period of several decades. Very favourable.

α-Capricornids Jul. 3 -Aug. 15

127 Jul. 30 5 20:28 (307) –9 +0.97 +0.24 23.0 0.0 Jul. 30 28 21.5 2.6 210003

182817

18.2 6.0 200004

316429

A good proportion of bright, slow-moving colourful meteors. Very favourable.

Southern δ-Aquarids

Jul. 12 -Aug. 23

128 Jul. 31 20 22:44 (341) –16 +0.95 +0.38 41.3 2.3 Jul. 31 0 21.5 2.6 230103

102021

18.2 6.0 210105

206548

Fine southern shower with double radiant. S. component is more active. Rich in faint meteors. Very favourable.

Piscis Austrinids Jul. 15 -Aug. 10

136 Aug. 9 5 23:32 (353) –21 +0.94 +0.40 43.8 2.5 Aug. 9 9 21.1 3.0 230103

051517

18.2 6.0 210105

206753

Southern shower in need of observation. Date of maximum and radiant location uncertain. Quite favourable.

Perseids Jul. 17-Aug. 24

140.0 Aug. 13d 07h 80+ 03:11 (048) +58.0 +1.34 +0.25 58.6 5.9 Aug. 13 13 20.9 3.2 210003

274366

- - - - Rich & fast meteors. High proportion of bright events leaving persistent trains. Unfavourable.

κ-Cygnids Aug. 3-25 141 Aug. 14 5 18:32 (278) +53 +0.40 +0.50 20.9 21.1 Aug. 14 14 20.9 3.2 210003

896439

- - - - Slow meteors with occasional bright fireballs. Date of max.may be as late as August 18. Unfavourable.

α-Aurigids Aug. 28 - Sep. 5

158 Sep. 1 5 06:04 (091) +39 +1.24 –0.01 65.6 7.5 Sep. 1 2 20.1 3.9 000204

193553

18.6 5.4 0405

0209

Short-lived outbursts in activity in 1994 and more recently in 2007. Favourable

September ε-Perseids

Sep. 5-21 167 Sep. 10 5 03:16 (049) +40 +1.17 +0.26 64.3 4.1 Sep. 10 11 19.7 4.2 200004

164878

18.7 5.2 010305

041414

Stronger than usual display seen in 2013.

Unfavourable. October Camelopardalids

Oct. 5-6 193 Oct. 6 5 11:04 (166) +79 ? ? 46.6 10.2 Oct. 6 8 18.7 4.9 200004

424250

- - - - Significant activity reported by video observers in 2005 and 2006. outburst in 2016. Favourable

Draconids Oct. 6-10 194.76 Oct. 8d 25 06:24 (096) +16 +0.70 +0.11 1.0 4.5 Oct. 8 10 18.6 5.0 192303

673617

- - - - Periodic shower connected with 21P/Giacobini-Zinner. weak activity expected. Unfavourable.

Orionids Oct. 2 - Nov. 7

209 Oct. 22-23 20 06:24 (096) +15.7 +0.71 +0.07 65.0 4.5 Oct. 22 24 18.1 5.4 230205

184453

19.3 4.2 000204

102939

Fast meteors, many with persistent trains. Flat maximum, with several sub-peaks. Good in 2007. Quite favourable.

Southern Taurids Sep. 10 - Nov. 20

223 Nov. 6 5 03:33 (053) +12.9 +0.74 +0.13 26.1 0.6 Nov. 6 9 18.5 5.1 200004

245033

19.1 4.5 210003

214131

Southern branch of the Taurid complex. Slow meteors. Dbl. radiant. Broad peak λ☼ =220°-230°. Quite favourable.

Northern Taurids Oct. 20-Dec. 10

230 Nov. 12 5 03:57 (059) +22.3 +0.70 +0.15 28.7 0.6 Nov. 12 15 17.5 5.9 200004

316041

19.7 3.8 210003

143223

Northern branch of the Taurid complex. Slow meteors. Unfavourable.

Leonids Nov. 6-30 236.0 Nov. 18d 23h 15 10:17 (154) +21.4 +0.59 –0.29 69.7 6.6 Nov. 18 21 17.4 6.1 000306

124059

19.8 3.7 020304

051523

Very fast meteors, many with persistent trains. Enhanced activity unlikely until the late 2020s. Unfavourable.

α- Monocerotids

Nov. 15-25

239 Nov. 21 ? 07:48 (117) +0.9 +0.95 –0.09 63.0 3.8 Nov. 21 24 17.4 6.1 000306

203832

19.9 3.6 230103

153752

Occasional very short-lived outbursts in activity, most recently in 1995 and possibly in 2016. Favourable.

Geminids Dec. 4-17 262.0 Dec. 14d 14h 100+ 07 34 (114) +32.3 +0.97 –0.23 33.6 2.1 Dec. 14 17 17.2 6.6 200004

256061

20.3 3.6 230103

102121

Richest of the annual showers, with slow meteors and a good proportion of bright events. Unfavourable.

Ursids Dec. 17-26

271 Dec. 23 10 14 40 (220) +75.4 +0.05 –0.31 32.9 8.7 Dec. 23 26 17.3 6.7 200106

384462

- - - - Under-observed shower which has produced outbursts in 1945, 1982, 1986 and in 2014. Very favourable.

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BAA Handbook 2019 Meteor Diary 101

METEORS METEORSShower Maximum Radiant Position Latitude 52°N Latitude 35°S

Notes

Maximum Daily Motion Twilight Radiant Twilight Radiant

NameNormal

Limits of Activity

λ☉ (2000.0)

°Date ZHR

at Max.R.A. Dec. R.A. Dec. Vg Local Time

of Transit DateAge of Moon Ends Begins UT Alt. Ends Begins UT Alt.

hh:mm (°) ° ° ° km/s h d h h h ° h h h °Quadrantids Dec. 28

-Jan. 12283.2 Jan. 4d 03h 80+ 15:18 (229) +49.5 +0.34 –0.25 40.7 8.5 Jan. 4 28 17.4 6.7 00

0306

214167

- - - - High activity, but with a rather narrow peak. Good in 2014. Bright events leave persistent trains. Very favourable.

April Lyrids Apr. 14-30

032.0 Apr. 22d 16h 15 18:07 (272) +33.1 +0.84 –0.34 47.3 4.1 Apr. 22 17 20.6 3.4 210003

174368

18.4 5.6 010305

092021

Normally rather moderate activity, but fine displays in 1803, 1922, 1982. Unfavourable.

η Aquarids Apr. 19-May 28

046 May 6-7 40 22:32 (338) –0.8 +0.92 +0.37 65.7 7.7 May 7 3 21.1 2.8 0203

9312

18.2 5.7 020406

052948

Fine southern shower, poorly seen from the UK. Fast meteors, many with persistent trains. Good in 2013.

Daytime Arietids May 22 – Jul. 2

077 Jun. 8 30? 02:56 (044) +24 +1.05 +0.28 41.1 9.9 Jun. 8 - - - 030915

116026

- - 061014

103106

Most active of the daytime showers. Good for radio observers. ZHR and radiant location uncertain.

June Bootids Jun. 22 - Jul. 2

096 Jun. 28 ? 14:52 (223) +48 ? ? 14.1 20.7 Jun. 28 26 22.5 1.6 220002

745640

- - - - Unexpected outburst with ZHR~100 m/h in 1998 June 27 after a quiescent period of several decades. Very favourable.

α-Capricornids Jul. 3 -Aug. 15

127 Jul. 30 5 20:28 (307) –9 +0.97 +0.24 23.0 0.0 Jul. 30 28 21.5 2.6 210003

182817

18.2 6.0 200004

316429

A good proportion of bright, slow-moving colourful meteors. Very favourable.

Southern δ-Aquarids

Jul. 12 -Aug. 23

128 Jul. 31 20 22:44 (341) –16 +0.95 +0.38 41.3 2.3 Jul. 31 0 21.5 2.6 230103

102021

18.2 6.0 210105

206548

Fine southern shower with double radiant. S. component is more active. Rich in faint meteors. Very favourable.

Piscis Austrinids Jul. 15 -Aug. 10

136 Aug. 9 5 23:32 (353) –21 +0.94 +0.40 43.8 2.5 Aug. 9 9 21.1 3.0 230103

051517

18.2 6.0 210105

206753

Southern shower in need of observation. Date of maximum and radiant location uncertain. Quite favourable.

Perseids Jul. 17-Aug. 24

140.0 Aug. 13d 07h 80+ 03:11 (048) +58.0 +1.34 +0.25 58.6 5.9 Aug. 13 13 20.9 3.2 210003

274366

- - - - Rich & fast meteors. High proportion of bright events leaving persistent trains. Unfavourable.

κ-Cygnids Aug. 3-25 141 Aug. 14 5 18:32 (278) +53 +0.40 +0.50 20.9 21.1 Aug. 14 14 20.9 3.2 210003

896439

- - - - Slow meteors with occasional bright fireballs. Date of max.may be as late as August 18. Unfavourable.

α-Aurigids Aug. 28 - Sep. 5

158 Sep. 1 5 06:04 (091) +39 +1.24 –0.01 65.6 7.5 Sep. 1 2 20.1 3.9 000204

193553

18.6 5.4 0405

0209

Short-lived outbursts in activity in 1994 and more recently in 2007. Favourable

September ε-Perseids

Sep. 5-21 167 Sep. 10 5 03:16 (049) +40 +1.17 +0.26 64.3 4.1 Sep. 10 11 19.7 4.2 200004

164878

18.7 5.2 010305

041414

Stronger than usual display seen in 2013.

Unfavourable. October Camelopardalids

Oct. 5-6 193 Oct. 6 5 11:04 (166) +79 ? ? 46.6 10.2 Oct. 6 8 18.7 4.9 200004

424250

- - - - Significant activity reported by video observers in 2005 and 2006. outburst in 2016. Favourable

Draconids Oct. 6-10 194.76 Oct. 8d 25 06:24 (096) +16 +0.70 +0.11 1.0 4.5 Oct. 8 10 18.6 5.0 192303

673617

- - - - Periodic shower connected with 21P/Giacobini-Zinner. weak activity expected. Unfavourable.

Orionids Oct. 2 - Nov. 7

209 Oct. 22-23 20 06:24 (096) +15.7 +0.71 +0.07 65.0 4.5 Oct. 22 24 18.1 5.4 230205

184453

19.3 4.2 000204

102939

Fast meteors, many with persistent trains. Flat maximum, with several sub-peaks. Good in 2007. Quite favourable.

Southern Taurids Sep. 10 - Nov. 20

223 Nov. 6 5 03:33 (053) +12.9 +0.74 +0.13 26.1 0.6 Nov. 6 9 18.5 5.1 200004

245033

19.1 4.5 210003

214131

Southern branch of the Taurid complex. Slow meteors. Dbl. radiant. Broad peak λ☼ =220°-230°. Quite favourable.

Northern Taurids Oct. 20-Dec. 10

230 Nov. 12 5 03:57 (059) +22.3 +0.70 +0.15 28.7 0.6 Nov. 12 15 17.5 5.9 200004

316041

19.7 3.8 210003

143223

Northern branch of the Taurid complex. Slow meteors. Unfavourable.

Leonids Nov. 6-30 236.0 Nov. 18d 23h 15 10:17 (154) +21.4 +0.59 –0.29 69.7 6.6 Nov. 18 21 17.4 6.1 000306

124059

19.8 3.7 020304

051523

Very fast meteors, many with persistent trains. Enhanced activity unlikely until the late 2020s. Unfavourable.

α- Monocerotids

Nov. 15-25

239 Nov. 21 ? 07:48 (117) +0.9 +0.95 –0.09 63.0 3.8 Nov. 21 24 17.4 6.1 000306

203832

19.9 3.6 230103

153752

Occasional very short-lived outbursts in activity, most recently in 1995 and possibly in 2016. Favourable.

Geminids Dec. 4-17 262.0 Dec. 14d 14h 100+ 07 34 (114) +32.3 +0.97 –0.23 33.6 2.1 Dec. 14 17 17.2 6.6 200004

256061

20.3 3.6 230103

102121

Richest of the annual showers, with slow meteors and a good proportion of bright events. Unfavourable.

Ursids Dec. 17-26

271 Dec. 23 10 14 40 (220) +75.4 +0.05 –0.31 32.9 8.7 Dec. 23 26 17.3 6.7 200106

384462

- - - - Under-observed shower which has produced outbursts in 1945, 1982, 1986 and in 2014. Very favourable.

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102 Variable Stars BAA Handbook 2019

VARIABLE STARSHeliocentric Times of Primary Minima

RZ Cassiopeiae: Magnitude 6.2 to 7.7, Duration 4.8 hours h h h h h hJan 1 16.9 Feb 1 18.7 Mar 1 6.5 Apr 1 8.3 May 1 5.5 Jun 1 7.3 2 21.6* 2 23.4* 2 11.2 2 13.0 2 10.2 2 12.0 4 2.3* 4 4.1* 3 15.9 3 17.7 3 14.9 3 16.7 5 7.0 5 8.8 4 20.6 4 22.4* 4 19.6 4 21.4 6 11.6 6 13.5 6 1.3* 6 3.1 6 0.2* 6 2.1 7 16.3 7 18.2 7 5.9 7 7.8 7 4.9 7 6.8 8 21.0* 8 22.8* 8 10.6 8 14.2 8 9.6 8 11.4 10 1.7* 10 3.5* 9 15.3 9 17.1 9 14.3 9 16.1 11 6.4 11 8.2 10 20.0 10 21.8 10 19.0 10 20.8 12 11.1 12 12.9 12 0.7* 12 2.5* 11 23.7* 12 1.5 13 15.8 13 17.6 13 5.4 13 7.2 13 4.4 13 6.2 14 20.4* 14 22.3* 14 10.1 14 11.9 14 9.0 14 10.9 16 1.1* 16 3.0* 15 14.7 15 16.6 15 13.7 15 15.6 17 5.8 17 7.6 16 19.4 16 21.3 16 18.4 16 20.3 18 10.5 18 12.3 18 0.1* 18 1.9* 17 23.1* 18 0.9 19 15.2 19 17.0 19 4.8 19 6.6 19 3.8 19 5.6 20 19.9* 20 21.7* 20 9.5 20 11.3 20 8.5 20 10.3 22 0.6* 22 2.4* 21 14.2 21 16.0 21 13.2 21 15.0 23 5.2 23 7.1 22 18.9 22 20.7 22 17.8 22 19.7 24 9.9 24 11.8 23 23.5* 24 1.4* 23 22.5 24 0.4 25 14.6 25 16.4 25 4.2 25 6.1 25 3.2 25 5.1 26 19.3 26 21.1* 26 8.9 26 10.8 26 7.9 26 9.7 27 0.0* 28 1.8* 27 13.6 27 15.4 27 12.6 27 14.4 29 4.7* 28 18.3 28 20.1 28 17.3 28 19.1 30 9.4 29 22.0* 30 0.8* 29 22.0 29 23.8 31 14.0 31 3.7 31 2.6 Jul 1 4.5 Aug 1 6.3 Sep 1 8.2 Oct 1 5.3 Nov 1 7.1 Dec 1 4.3 2 9.2 2 11.0 2 12.8 2 10.0 2 11.8 2 9.0 3 13.9 3 15.7 3 17.5 3 14.7 3 16.5 3 13.7 4 18.5 4 20.4 4 22.2 4 19.4 4 21.2* 4 18.4 5 23.2 6 1.1* 6 2.9 6 0.1* 6 1.9* 5 23.0* 7 3.9 7 5.8 7 7.6 7 4.7 7 6.6 7 3.7* 8 8.6 8 10.4 8 12.3 8 9.4 8 11.3 8 8.4 9 13.3 9 15.1 9 17.0 9 14.1 9 16.0 9 13.1 10 18.0 10 19.8 10 21.6 10 18.8 10 20.6* 10 17.8 11 22.7 12 0.5* 12 2.3 11 23.5* 12 1.3* 11 22.5* 13 3.3 13 5.2 13 7.0 13 4.2 13 6.0 13 3.2* 14 8.0 14 9.9 14 11.7 14 8.9 14 10.7 14 7.8 15 12.7 15 14.6 15 16.4 15 13.5 15 15.4 15 12.5 16 17.4 16 19.2 16 21.1 16 18.2 16 20.1* 16 17.2 17 22.1 17 23.9* 18 1.8* 17 22.9* 18 0.8* 17 21.9* 19 2.8 19 4.6 19 6.4 19 3.6* 19 5.4 19 2.6* 20 7.5 20 9.3 20 11.1 20 8.3 20 10.1 20 7.3 21 12.1 21 14.0 21 15.8 21 13.0 21 14.8 21 12.0 22 16.8 22 18.7 22 20.5 22 17.7 22 19.5* 22 16.6 23 21.5 23 23.4* 24 1.2* 23 22.3* 24 0.2* 23 21.3* 25 2.2 25 4.0 25 5.9 25 3.0* 25 4.9 25 2.0* 26 6.9 26 8.7 26 10.6 26 7.7 26 9.6 26 6.7 27 11.6 27 13.4 27 15.3 27 12.4 27 14.2 27 11.4 28 16.3 28 18.1 28 19.9 28 17.1 28 18.9 28 16.1 29 20.9 29 22.8* 30 0.6* 29 21.8* 29 23.6* 29 20.8* 31 1.6 31 3.5 31 2.5* 31 1.4* Minima marked with an asterisk (*) are favourable from the British Isles, taking into account the altitude of the variable and the distance of the Sun below the horizon (based on longitude 0° and latitude 52° N).

Heliocentric times must be UTC corrected for the light–time to the Sun. To calculate this, use the program on the Computing Section website. http://britastro.org/computing/applets_dt.html

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BAA Handbook 2019 Variable Stars 103

b Persei (Algol): Magnitude 2.1 to 3.4, Duration 9.6 hours

h h h h h h

Jan 3 15.9 Feb 1 8.1 Mar 2 0.2* Apr 2 13.2 May 1 5.4 Jun 1 18.3 6 12.7 4 4.9 4 21.1* 5 10.0 4 2.2 4 15.2 9 9.6 7 1.7* 7 17.9 8 6.8 6 23.0 7 12.0 12 6.4 9 22.5* 10 14.7 11 3.7 9 19.8 10 8.8 15 3.2* 12 19.3 13 11.5 14 0.5 12 16.6 13 5.6 18 0.0* 15 16.2 16 8.3 16 21.3 15 13.4 16 2.4 20 20.8* 18 13.0 19 5.1 19 18.1 18 10.3 18 23.2 23 17.6 21 9.8 22 1.9* 22 14.9 21 7.1 21 20.0 26 14.5 24 6.6 24 22.8* 25 11.7 24 3.9 24 16.9 29 11.3 27 3.4 27 19.6 28 8.6 27 0.7 27 13.7 30 16.4 29 21.5 30 10.5 Jul 3 7.3 Aug 3 20.3 Sep 1 12.4 Oct 3 1.4* Nov 3 14.4 Dec 2 6.5 6 4.1 6 17.1 4 9.3 5 22.2* 6 11.2 5 3.4* 9 0.9 9 13.9 7 6.1 8 19.0 9 8.0 8 0.2* 11 21.8 12 10.7 10 2.9 11 15.9 12 4.8 10 21.0* 14 18.6 15 7.5 12 23.7* 14 12.7 15 1.6* 13 17.8 17 15.4 18 4.4 15 20.5 17 9.5 17 22.5* 16 14.6 20 12.2 21 1.2* 18 17.3 20 6.3 20 19.3 19 11.4 23 9.0 23 22.0 21 14.1 23 3.1* 23 16.1 22 8.2 26 5.8 26 18.8 24 11.0 25 23.9* 26 12.9 25 5.1 29 2.6 29 15.6 27 7.8 28 20.7 29 9.7 28 1.9* 31 23.5 30 4.6 31 17.6 30 22.7*

RS Canum Venaticorum 7.9 to 9.1, Duration 13 hours

h h h h h hJan 4 11.2 Feb 2 6.1 Mar 3 0.9* Apr 5 14.9 May 4 9.8 Jun 2 4.7 9 6.3 7 1.2* 7 20.1 10 10.1 9 4.9 6 23.8 14 1.5* 11 20.3 12 15.2 15 5.2 14 0.1 11 19.0 18 20.6 16 15.5 17 10.4 20 0.4 18 19.2 16 14.1 23 15.8 21 10.6 22 5.5 24 19.5 23 14.4 21 9.3 28 10.9 26 5.8 27 0.6* 29 14.7 28 9.5 26 4.4 31 19.8 30 23.5 Jul 5 18.7 Aug 3 13.6 Sep 1 8.4 Oct 4 22.4 Nov 2 17.3 Dec 1 12.2 10 13.8 8 8.7 6 3.6 9 17.6 7 12.5 6 7.3 15 9.0 13 3.8 10 22.7 14 12.7 12 7.6 11 2.5* 20 4.1 17 23.0 15 17.9 19 7.9 17 2.7 15 21.6* 24 23.3 22 18.1 20 13.0 24 3.0 21 21.9 20 16.8 29 18.4 27 13.3 25 8.2 28 22.2 26 17.0 25 11.9 30 3.3 30 7.0

VARIABLE STARS

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104 Variable Stars BAA Handbook 2019

MIRA STARSApproximate dates of maxima and minima for Mira stars on the programme of the BAA Variable Star Section, together with (usually) the mean visual range(P), and fraction of the period taken in rising from minimum (m) to maximum (M) for each star. The predictions, which are subject to inevitable uncertainty, use data from the American Association of Variable Star Observers.

Star Range Period Max–Min Date of Max. Date of Min. Max Min Period d

R And 6.9 14.3 409 0.38 Aug./Sep Mar./Apr.W And 7.4 13.7 396 0.42 Apr. Nov./Dec.RW And 8.7 14.8 430 0.36 Mar. Dec.R Aqr 6.5 10.3 387 0.42 Jun./Jul. Jan.R Aql 6.1 11.5 284 0.42 May Jan., Oct.UV Aur* 7.4 10.6 394 0.50 Oct. Mar./Apr.V Cam 9.9 15.4 522 0.31 Jan. -X Cam 8.1 12.6 144 0.49 Apr., Sep. Jan./Feb., Jun./Jul., Nov. SU Cnc* 10.5 [15.4 187 0.43 Feb./Mar., Aug./Sep. Jun., Dec.U CVn 9.9 14.6 346 0.37 Jun./Jul. Feb./Mar.RT CVn* 9.9 [15.0 254 0.45 Feb., Oct./Nov. Jul.S Cas 9.7 14.8 612 0.43 Feb./Mar. -T Cas 7.9 11.9 445 0.56 Aug. Jan./Feb.ο Cet 3.4 9.3 332 0.38 Oct./Nov. Jun./Jul.R Com 8.5 14.2 363 0.38 Jul./Aug. Mar.S CrB 7.3 12.9 360 0.35 Aug. Apr.V CrB 7.5 11.0 358 0.41 Sep./Oct. MayW CrB 8.5 13.5 238 0.45 Feb./Mar., Oct. Jun./Jul.R Cyg 7.5 13.9 426 0.35 Aug./Sep. Mar./Apr.S Cyg 10.3 16.0 323 0.50 Jun./Jul. Jan./Feb., Dec.V Cyg 9.1 12.8 421 0.46 Jul. -χ Cyg 5.2 13.4 408 0.41 - Jul./Aug.T Dra 9.6 12.3 422 0.44 Sep./Oct. Mar./Apr.RU Her 8.0 13.7 485 0.43 Jan. Oct.SS Her 9.2 12.4 107 0.48 Apr., Jul./Aug., Feb., May/Jun., Nov. Sep. R Hya 4.5 9.5 389 0.49 Oct. Apr.SU Lac* 10.3 [15.0 302 0.40 Aug./Sep. Apr./MayRS Leo* 9.7 [15.5 208 0.31 Jan./Feb., Aug./Sep. Jun.W Lyn 9.9 ≈15.0 295 0.40 Feb., Nov./Dec. Aug.X Lyn 10.2 ≈15.0 321 0.40 May 2018 Dec./2019 Jan., Nov.X Oph 6.8 8.8 329 0.53 Jan./Feb., Dec., Jul. 2020 Jan.U Ori 6.3 12.0 368 0.38 Apr./May Dec.R Ser 6.9 13.4 356 0.41 May/Jun. Jan., Dec./2020 Jan.T UMa 7.7 12.9 257 0.41 Jul./Aug. Apr., Dec.

* Extreme range is given [ Fainter than

≈ Approximately

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BAA Handbook 2019 Variable Stars 105

VARIABLE STAR OF THE YEAR

Variable Star of the Year – RS Canum Venaticorum

RS CVn was discovered in 1914 by Madame Lydia Ceraski who was the wife of the Direc-tor of the Moscow Observatory. She was not a trained astronomer and did not hold an as-tronomical post but undertook, like the Harvard ‘computers’, to examine the photographic plates that were produced by the Observatory. Her discovery was, therefore, not made by direct observation. The discovery was published under her husband’s name though he ac-knowledged her role. She discovered many variable stars. From the plates she recognised a new Algol eclipsing binary system. The peculiarities of the light curve of the system confused astronomers for some time to come. It was not until 1946 that Otto Struve identi-fied the ‘RS’ group of eclipsing binaries. Further work was done on the characteristics of the group by Oliver (1974) and Hall (1976).

RS CVn is an eclipsing binary of the Algol type. It has a period of about 4.8 days. The primary eclipse lasts about 13 hours with a depth of about one magnitude. The system fades from around 8 to a magnitude of 9.1. The secondary eclipse is much shallower with a depth of 0.2 magnitude. The primary eclipse can be detected visually with binoculars but DSLR/CCD photometry will be needed to study the secondary eclipse.

RS CVn is the type system of a sub-class of eclipsing binaries. Such systems have the designation RS so that RS CVn is an EA/RS system. This sub class consists of stars that are ‘chromospherically active’. They have cool, large stellar spots which are so large that they can cause variations of up to 0.4 magnitude in the light curve. Such variations within the light curve can be detected by DSLR photometry particularly if the measurements are obtained at a high quality dark sky site where atmospheric turbulence is minimal.

The variations in the light curve are repeated for a period of time, in between eclipses, at intervals similar to the orbital period. IBVS 5838 (2008) reports on the starspot variations of the V841 Cen system. The title of the report is ‘A Large, Long Period Spot Wave’. The amplitude of the variation in that system was 0.4 magnitude. The variation was stable for over six months. Another report was made in IBVS 5772 (2007). The title is ‘GSC 3372-0296 is a new short period Eclipsing RS CVn Variable’. The starspot(s) are about 0.2 magnitude. The report publishes a light curve which illustrates what might be seen when observing this type of system.

Details of the variations of RS CVn will be of interest to all those studying ‘chromospheri-cally active’ stars. Such details will be obtained by systematic out-of-eclipse measure-ments. If a starspot is identified spectroscopists should be alerted.

RS CVn, a giant orange/red star 522 light years from Earth, is straightforward to find out of eclipse with a magnitude of around 8.00. You star hop with the naked eye by going to the end of the handle of the Plough and then to the brightest star in the constellation Canes Venatici, which has a magnitude of around 2.84, called Cor Caroli. From this star, using binoculars it is easy to find the nearby star, 14 Canum Venaticorum , which has a magnitude of 5.18. RS CVn will be in the same field of view as 14 Canum Venaticorum and, as the BAAVSS chart (253.02) illustrates, it is associated with an easily recognizable asterism of 5 stars including itself.

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106 Variable Stars BAA Handbook 2019

RS

CA

NU

M V

EN

AT

ICO

RU

M L

IGH

T C

UR

VE

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BAA Handbook 2019 Variable Stars 107

RS CANUM VENATICORUM FINDER CHART

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108 Double Stars BAA Handbook 2019

EPHEMERIDES OF VISUAL BINARY STARSInspection of the two–point ephemeris will indicate whether a pair is closing, relatively static, or opening up, and whether motion is direct or retrograde. A fast–mover of long period is probably near periastron, while a slow–mover of short period is likely to be near apastron. The orbital ele-ments employed for the computation are those published in the Sixth Catalog of Orbits of Visual Binary Stars, by William I. Hartkopf and Brian D. Mason, U.S. Naval Observatory:

http://ad.usno.navy.mil/wds/orb6.html

2000.0 2019.0 2020.0Star Name ADS RA Dec. Mags. Period PA Dist. PA Dist. h m ° ′ y ° ″ ° ″85 Peg 17175 0 02.2 +27 05 5.8 8.9 26 112.2 0.70 123.0 0.75OΣ 4 221 0 16.7 +36 29 7.9 9.8 109 345.5 0.16 333.5 0.17λ Cas 434 0 31.8 +54 31 5.3 5.6 246 243.6 0.13 252.6 0.11β 395 520 0 37.3 –24 46 6.6 6.2 25 122.8 0.48 130.9 0.33η Cas 671 0 49.1 +57 49 3.5 7.3 479 325.9 13.38 326.4 13.41 36 And 755 0 55.0 +23 38 6.1 6.5 168 333.5 1.17 334.6 1.18Howe 4 1223 1 33.7 –12 13 9.2 9.3 142 329.7 0.86 329.4 0.86Dunlop 5 … 1 39.8 –56 12 5.7 5.9 475 186.1 11.63 185.9 11.63Σ 186 1538 1 55.9 +01 51 6.7 6.8 166 73.7 0.67 74.8 0.65α Psc 1615 2 02.0 +02 46 4.1 5.1 3267 260.8 1.84 260.2 1.84 10 Ari 1631 2 03.7 +25 56 5.8 7.8 325 348.5 1.55 349.0 1.57Σ 228 1709 2 14.0 +47 29 6.5 7.2 145 306.6 0.61 308.9 0.59h 3494 .. 2 19.8 –35 27 9.0 9.1 475 240.9 2.31 240.5 2.32ι Cas AB 1860 2 29.1 +67 24 4.6 6.9 620 227.5 2.63 227.3 2.64Σ 305 2122 2 47.5 +19 22 7.5 8.2 531 306.9 3.60 306.8 3.59 α For 2402 3 12.1 –28 59 3.9 7.1 269 300.6 5.43 300.7 5.45Σ 367 2416 3 14.0 +00 44 8.1 8.1 420 130.0 1.27 129.6 1.277 Tau 2616 3 34.4 +24 28 6.6 6.8 522 350.5 0.76 350.2 0.77OΣ 65 2799 3 50.3 +25 35 5.7 6.5 61 202.4 0.53 202.7 0.5540 Eri BC 3093 4 15.3 –07 39 10.0 11.4 230 330.8 8.16 330.5 8.09 OΣ 77 AB 3082 4 15.9 +31 42 8.0 8.2 188 305.2 0.49 306.6 0.48Hu 445 3614 5 01.7 +20 50 9.3 8.4 166 155.1 0.34 157.4 0.3414 Ori 3711 5 07.9 +08 30 5.7 6.6 197 284.6 0.98 283.1 0.98η Gem 4841 6 14.9 +22 30 3.5 6.1 474 251.8 1.61 251.6 1.61OΣ 149 5234 6 36.4 +27 17 7.1 8.9 119 278.7 0.73 277.6 0.73 12 Lyn AB 5400 6 46.2 +59 27 5.4 6.0 908 65.5 1.91 65.1 1.921 Lyn 5514 6 53.1 +59 27 6.0 6.5 316 356.1 0.31 357.9 0.32α Gem 6175 7 34.6 +31 53 1.9 2.9 460 52.7 5.31 52.2 5.389 Pup 6420 7 51.8 –13 54 5.6 6.4 23 303.8 0.44 307.2 0.39ζ Cnc AB 6650 8 12.2 +17 39 5.3 6.3 60 7.0 1.13 3.7 1.13

ζ Cnc AB–C 6650 8 12.2 +17 39 4.9 5.8 1115 64.5 5.93 64.1 5.93β 208 6914 8 39.1 –22 40 5.3 6.8 123 62.7 0.45 68.2 0.40I 314 .. 8 39.4 –36 36 6.4 7.9 67 241.1 0.88 240.9 0.89δ Vel .. 8 44.7 –54 43 1.9 5.5 147 203.0 0.69 198.7 0.77ε Hya AB–C 6993 8 46.8 +06 25 3.4 5.0 15 252.9 0.22 271.7 0.18 Σ 1338 7307 9 21.0 +38 11 6.7 7.0 303 320.1 1.00 321.9 1.00ω Leo 7390 9 28.5 +09 03 5.6 7.2 118 113.7 0.87 114.7 0.89γ Sex 7555 9 52.5 –08 06 5.4 6.4 78 37.7 0.49 36.1 0.48γ Leo 7724 10 20.0 +19 50 2.3 3.6 554 126.5 4.73 126.6 4.73β 411 7846 10 36.1 –26 41 6.6 7.7 159 303.3 1.33 302.9 1.33

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BAA Handbook 2019 Double Stars 109

ξ UMa AB 8119 11 18.2 +31 32 4.3 4.8 60 156.6 2.10 152.5 2.19ι Leo 8148 11 23.9 +10 32 4.0 6.7 186 92.7 2.20 92.0 2.22BrsO 5 .. 11 24.7 –61 39 7.6 8.7 399 249.0 7.67 249.2 7.71OΣ 235 8197 11 32.3 +61 05 5.6 7.5 73 44.3 0.95 46.4 0.96Σ 1639 8539 12 24.4 +25 35 6.7 7.8 575 322.8 1.85 322.7 1.86 β 28 8573 12 30.1 –13 24 6.4 9.5 151 348.5 2.14 349.1 2.14γ Cen .. 12 41.5 –48 58 2.8 2.8 84 35.2 0.30 28.5 0.39γ Vir 8630 12 41.7 –01 27 3.4 3.5 169 358.8 2.81 357.4 2.9335 Com 8695 12 53.3 +21 15 5.1 7.0 539 200.9 1.18 201.7 1.19I 83 .. 12 56.7 –47 41 7.3 7.6 173 236.8 0.86 237.2 0.86 78 UMa 8739 13 0.7 +56 22 5.0 7.8 105 142.6 0.63 151.0 0.59A1609 AB 8901 13 25.8 +44 30 9.4 8.7 44 75.9 0.29 84.6 0.2625 CVn 8974 13 37.5 +36 18 4.9 6.9 228 93.9 1.67 93.6 1.66α Cen .. 14 39.6 –60 50 0.0 1.3 80 337.1 4.92 345.3 5.49ζ Boo 9343 14 41.1 +13 44 4.4 4.5 125 283.3 0.29 280.1 0.25 φ309 .. 14 46.2 –21 11 7.3 7.3 13 186.9 0.17 217.2 0.12ξ Boo 9413 14 51.4 +19 06 4.7 6.9 152 297.8 5.30 296.4 5.21OΣ 288 9425 14 53.4 +15 42 6.8 7.5 313 156.2 0.96 155.6 0.95H 4707 .. 14 54.2 –66 25 7.5 8.0 346 266.7 1.26 266.1 1.2844 Boo 9494 15 03.8 +47 39 5.2 6.1 210 90.6 0.39 112.0 0.27 η CrB 9617 15 23.2 +30 17 5.6 5.9 41 256.0 0.39 279.9 0.36γ Lup .. 15 35.1 –41 10 2.9 4.4 190 276.1 0.82 276.0 0.82π2 UMi 9769 15 39.6 +79 59 7.3 8.1 172 20.9 0.61 20.6 0.60ξ Sco AB 9909 16 04.4 –11 22 5.1 4.8 46 10.0 1.12 11.5 1.13σ CrB AB 9979 16 14.7 +33 52 6.1 6.5 136 238.7 7.24 238.9 7.27 λ Oph 10087 16 30.9 +01 59 4.1 5.1 129 44.4 1.41 45.2 1.40ζ Her 10157 16 41.3 +31 36 2.9 5.4 34 111.7 1.36 106.1 1.4020 Dra 10279 16 56.4 +65 02 7.0 7.3 422 66.3 1.14 66.3 1.13MlbO 4 AB .. 17 19.0 –34 59 6.3 7.3 42 22.8 0.52 347.2 0.78BrsO 13 .. 17 19.1 –46 38 5.6 8.8 953 258.6 10.69 258.8 10.76 26 Dra 10660 17 35.0 +61 53 5.2 8.5 76 207.7 0.36 191.5 0.45τ Oph 11005 18 03.1 –08 11 5.2 5.8 257 288.8 1.49 289.3 1.4770 Oph 11046 18 05.5 +02 30 4.2 6.1 88 122.5 6.56 121.7 6.61h 5014 .. 18 06.8 –43 25 5.6 5.6 450 358.1 1.74 357.7 1.75OΣ 358 11483 18 35.9 +16 59 6.9 7.0 380 144.2 1.49 143.6 1.48 ε1 Lyr AB 11635 18 44.3 +39 40 5.1 6.1 1725 344.7 2.31 344.3 2.31ε2 Lyr CD 11635 18 44.3 +39 40 5.2 5.3 724 74.4 2.40 74.0 2.40γ CrA .. 19 06.4 –37 04 4.5 6.4 122 332.4 1.48 328.5 1.50δ Cyg 12880 19 45.0 +45 08 2.8 6.2 918 215.6 2.76 215.1 2.77λ Cyg 14296 20 47.4 +36 29 5.4 5.8 12 125.1 0.04 105.4 0.05 4 Aqr 14360 20 51.4 –05 38 6.4 7.4 201 31.7 0.76 32.5 0.74ε Equ AB 14499 20 59.1 +04 18 5.9 6.3 104 279.4 0.13 275.4 0.07τ Cyg 14787 21 14.8 +38 03 3.8 6.5 49 187.8 0.99 183.7 1.01μ Cyg 15270 21 44.1 +28 45 4.7 6.1 789 325.3 1.48 326.4 1.4653 Aqr 15934 22 26.6 –16 45 6.2 6.3 3500 77.6 1.32 81.7 1.33 Kr 60 15972 22 28.0 +57 42 9.9 11.4 45 229.6 1.73 217.2 1.89ζ Aqr AB 15971 22 28.8 –00 01 4.3 4.4 540 156.2 2.26 155.1 2.29π Cep 16538 23 07.9 +75 23 4.6 6.8 163 2.6 1.12 3.4 1.12β 80 16665 23 18.9 +05 24 8.1 9.3 97 251.8 0.81 253.5 0.8372 Peg 16836 23 34.0 +31 20 5.6 6.1 492 106.5 0.58 107.1 0.58

EPHEMERIDES OF VISUAL BINARY STARS 2000.0 2019.0 2020.0Star Name ADS RA Dec. Mags. Period PA Dist. PA Dist. h m ° ′ y ° ″ ° ″

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110 Bright Stars BAA Handbook 2019

BRIGHT STARSFOR EPOCH 2019.5

Name RA Dec. V Name RA Dec. V h m s ° ' " h m s ° ' "

α And 0 09 24.0 +29 11 53 2.07 α UMa 11 04 54.9 +61 38 44 1.81β Cas* 0 10 13.8 +59 15 26 2.28 β Leo 11 50 3.2 +14 27 47 2.14α Cas 0 41 37.6 +56 38 38 2.24 α Cru† 12 27 41.8 –63 12 25 0.77β Cet 0 44 34.0 –17 52 48 2.04 γ Cru* 12 32 15.6 –57 13 20 1.59β And 1 10 49.8 +35 43 24 2.07 γ Cen† 12 42 36.1 –49 04 00 2.20

α Eri 1 38 26.3 –57 08 18 0.45 β Cru* 12 48 52.4 –59 47 42 1.25γ And 2 05 6.3 +42 25 21 2.10 ε UMa* 12 54 52.9 +55 51 15 1.76α Ari 2 08 16.6 +23 33 14 2.01 ζ UMa 13 24 42.5 +54 49 26 2.23α UMi* 2 56 24.3 +89 20 46 1.97 α Vir* 13 26 13.4 –11 15 45 0.98α Per* 3 09 26.7 +41 01 46 2.09 ε Cen 13 41 8.1 –53 33 53 2.29

α Per 3 25 43.5 +49 55 44 1.79 η UMa 13 48 18.4 +49 12 59 1.85η Tau 3 48 38.9 +24 09 50 2.85 β Cen* 14 05 13.0 –60 27 58 0.61α Tau 4 37 2.5 +16 32 49 0.87 θ Cen 14 07 50.2 –36 27 54 2.06β Ori 5 15 28.6 –8 10 50 0.18 α Boo 14 16 33.1 +19 04 54 –0.05α Aur* 5 18 8.0 +46 00 57 0.08 η Cen* 14 36 45.2 –42 14 32 2.33

γ Ori 5 26 10.7 +6 21 57 1.64 α Cen cg* 14 40 56.4 –60 54 57 –0.01β Tau 5 27 31.6 +28 37 20 1.65 α Lup* 14 43 14.2 –47 28 14 2.30δ Ori* 5 33 0.2 –0 17 10 2.25 ε Boo 14 45 50.3 +26 59 34 2.35ε Ori 5 37 12.2 –1 11 27 1.69 β UMi 14 50 40.1 +74 04 33 2.07ζ Ori 5 41 44.6 –1 56 01 1.74 α CrB* 15 35 30.8 +26 39 00 2.22

κ Ori 5 48 40.9 –9 39 51 2.07 δ Sco 16 01 29.4 –22 40 33 2.29α Ori* 5 56 13.7 +7 24 33 0.45 α Sco* 16 30 36.4 –26 28 25 1.06β Aur* 6 00 57.6 +44 56 50 1.90 α TrA 16 50 44.8 –69 03 38 1.91β CMa* 6 23 33.5 –17 58 01 1.98 ε Sco 16 51 25.8 –34 19 37 2.29α Car* 6 24 23.1 –52 42 25 –0.62 λ Sco* 17 34 56.1 –37 06 58 1.62

γ Gem 6 38 50.2 +16 22 51 1.93 α Oph 17 35 50.4 +12 32 50 2.08α CMa 6 46 0.1 –16 44 41 –1.44 θ Sco 17 38 43.3 –43 00 30 1.86ε CMa 6 59 23.6 –28 59 59 1.50 γ Dra 17 57 3.6 +51 29 14 2.24δ CMa 7 09 11.1 –26 25 31 1.83 ε Sgr 18 25 27.9 –34 22 25 1.79α Gem† 7 35 50.2 +31 50 36 1.58 α Lyr 18 37 36.0 +38 48 10 0.03

α CMi 7 40 19.4 +5 10 24 0.40 σ Sgr 18 56 28.4 –26 16 15 2.05β Gem 7 46 30.4 +27 58 39 1.16 β Cyg† 19 31 30.5 +28 00 06 3.05ζ Pup 8 04 16.2 –40 03 32 2.21 α Aql 19 56 44.1 +8 55 16 0.76γ Vel* 8 10 8.0 –47 23 41 1.75 γ Cyg 20 22 55.7 +40 19 12 2.23ε Car* 8 22 54.7 –59 34 22 1.86 α Pav 20 27 10.7 –56 40 15 1.94

δ Vel 8 45 14.5 –54 46 51 1.93 α Cyg 20 42 5.8 +45 21 03 1.25λ Vel* 9 08 42.9 –43 30 43 2.23 α Cep 21 19 2.6 +62 40 07 2.45β Car 9 13 24.4 –69 47 52 1.67 ε Peg* 21 45 8.6 +9 57 55 2.38ι Car* 9 17 36.7 –59 21 27 2.21 β Gru 22 09 27.2 –46 51 57 1.73α Hya 9 28 32.7 –8 44 38 1.99 α Gru* 22 43 49.4 –46 46 55 2.07

α Leo 10 09 24.5 +11 52 16 1.36 α PsA 22 58 43.4 –29 31 07 1.17γ Leo† 10 21 2.7 +19 44 32 2.01 β Peg* 23 04 43.3 +28 11 20 2.44β UMa 11 03 0.4 +56 16 39 2.34 α Peg 23 05 44.0 +15 18 38 2.49

* = Variable star † = Double star

Note: double star co–ordinates refer to the brighter component, but magnitude refers to the combined light.

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BAA Handbook 2019 Active Galaxies 111

ACTIVE GALAXIES

Object RA Dec. Const. Type V* U.2000 (2000.0) Chart No. h m °3C 66A 2 22 +43.0 And BL Lac 14.0 – 16.3 62NGC 1275 3 20 +41.5 Per Seyfert 13.2 – 13.7 633C 120 (BW Tau) 4 33 +05.4 Tau BL Lac 13.7 – 14.6 178S5 0716+71 7 22 +71.3 Cam BL Lac 12.3 – 15.3 21OJ+287 8 54 +20.1 Cnc BL Lac 12.4 – 16.0 142Markarian 421 11 04 +38.2 UMa BL Lac 12.3 – 14.2 106NGC 4151 12 10 +39.4 CVn Seyfert 11.0 – 12.4 74W Comae 12 21 +28.2 Com BL Lac 11.5 – 16.0 1483C 273 12 26 +02.3 Vir Quasar 12.3 – 13.3 2383C 279 12 56 –05.8 Vir Quasar 11.5 – 17.0 239BL Lacertae 22 02 +42.3 Lac BL Lac 12.5 – 15.5 87

*Approximate range

FINDER CHARTS FOR ACTIVE GALAXIES

Charts for all of the active galaxies listed above have been included in previous BAA Handbooks and are listed below. Object BAA VSS Chart Handbook Year 3C 66A 309.01 2010 NGC1275 296.01 2008 BW Tau 320.01 2011 S5 0716+71 310.01 2009 OJ+287 208.02 2004 Markarian 421 243.01 2001 NGC4151 297.01 2007 W Com 148.03 2002 3C 273 244.01 2003 3C 279 151.02 2006 BL Lac 242.01 2005 Direct links to individual BAA VSS charts for the Active Galaxies can be found in a more detailed table of these galaxies, on the Computing Section website at:

http://britastro.org/computing/handbooks_active.html

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112 Time BAA Handbook 2019

TIMEUniversal Time (UT, Greenwich Mean Time beginning at midnight) is used generally throughout the Handbook.

Terrestrial Time (TT) is the uniform time system used in computing the ephemerides of the bodies of the Solar System. TT is currently ahead of UT by a small amount ΔT which must be determined by observations; thus

TT = UT + ΔTThe value of ΔT for July 2019 is estimated to be about 69.7 seconds.

Greenwich Mean Astronomical Time (GMAT), or Greenwich Mean Time beginning at noon, was in use before 1925 January 1, and many astronomical records prior to that date are referred to this system. To convert UT to GMAT subtract 12 hours, and to convert GMAT to UT add 12 hours.

Greenwich Sidereal Time (GST) is given in the table below at 0h UT. It may be obtained with sufficient accuracy for setting the circles of a telescope at any other time by adding 3.94 minutes for every complete day after a tabulated date, together with the correction, ΔT, for parts of a day from the table which follows:

For greater accuracy (±0.2S) use the equation : GST (at 0h UT) = '6.624992h + 0.06570982h dwhere d is the number of days from January 0.

The tabulated sidereal time is actually the mean sidereal time. The difference between mean and apparent sidereal time is never more than about 1.2 seconds.Local Sidereal Time (LST) and Local Hour Angle (LHA) are found from LST = GST + λ LHA = LST – RAWhere λ is the longitude, expressed in time, measured positive eastwards from Greenwich.

The Julian Date, in which the day begins at noon, is used in accurate computing work and is given in the table on p.111.

The Sun’s Longitude is used as a measure of time in meteor work. It may be interpolated from the table on p.111.

Time ΔT Time ΔT Time ΔT Time ΔT h m h m h m h m 0 00.0 m 5 46.9 m 11 52.2 m 17 57.4 m 0.0 1.0 2.0 3.0 0 18.2 6 23.5 12 28.7 18 33.9 0.1 1.1 2.1 3.1 0 54.7 7 00.0 13 05.3 19 10.5 0.2 1.2 2.2 3.2 1 31.3 7 36.5 13 41.7 19 47.0 0.3 1.3 2.3 3.3 2 07.8 8 13.0 14 18.3 20 23.5 0.4 1.4 2.4 3.4 2 44.3 8 49.6 14 54.8 21 00.0 0.5 1.5 2.5 3.5 3 20.8 9 26.1 15 31.3 21 36.6 0.6 1.6 2.6 3.6 3 57.4 10 02.6 16 07.8 22 13.1 0.7 1.7 2.7 3.7 4 33.9 10 39.1 16 44.4 22 49.6 0.8 1.8 2.8 3.8 5 10.4 11 15.6 17 20.9 23 26.1 0.9 1.9 2.9 3.9

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BAA Handbook 2019 Time 113

TIME Julian Sun's Long. Julian Sun's Long.2019 Date GST 2000.0 2019 Date GST 2000.0 2458 h m ° 2458 h m °

Dec 29 481.5 6 29.61 276.94 Jul. 2 666.5 18 38.99 99.60 5.10 4.77Jan. 3 486.5 6 49.33 282.04 7 671.5 18 58.71 104.37 5.10 4.76 8 491.5 7 09.04 287.14 12 676.5 19 18.42 109.13 5.09 4.77 13 496.5 7 28.75 292.23 17 681.5 19 38.13 113.90 5.10 4.77 18 501.5 7 48.47 297.33 22 686.5 19 57.85 118.67 5.08 4.77 23 506.5 8 08.18 302.41 27 691.5 20 17.56 123.44 5.09 5.02 28 511.5 8 27.89 307.50 Aug. 1 665.5 18 37.27 128.46 5.08 4.55Feb. 2 516.5 8 47.61 312.58 6 701.5 20 56.98 133.01 5.07 4.79 7 521.5 9 07.32 317.65 11 706.5 21 16.70 137.80 5.06 4.80 12 526.5 9 27.03 322.71 16 711.5 21 36.41 142.60 5.05 4.81 17 531.5 9 46.74 327.76 21 716.5 21 56.12 147.41 5.04 4.81 22 536.5 10 06.46 332.80 26 721.5 22 15.84 152.22 5.03 4.83 27 541.5 10 26.17 337.83 31 726.5 22 35.55 157.05 5.02 4.84Mar. 4 546.5 10 45.88 342.85 Sep. 5 731.5 22 55.26 161.89 5.01 4.86 9 551.5 11 05.60 347.86 10 736.5 23 14.97 166.75 5.00 4.86 14 556.5 11 25.31 352.86 15 741.5 23 34.69 171.61 4.98 4.87 19 561.5 11 45.02 357.84 20 746.5 23 54.40 176.48 4.96 4.89 24 566.5 12 04.73 2.80 25 751.5 0 14.11 181.37 4.95 4.91 29 571.5 12 24.45 7.75 30 756.5 0 33.83 186.28 4.94 4.92Apr. 3 576.5 12 44.16 12.69 Oct. 5 761.5 0 53.54 191.20 4.93 4.93 8 581.5 13 03.87 17.62 10 766.5 1 13.25 196.13 4.91 4.94 13 586.5 13 23.59 22.53 15 771.5 1 32.97 201.07 4.89 4.96 18 591.5 13 43.30 27.42 20 776.5 1 52.68 206.03 4.88 4.98 23 596.5 14 03.01 32.30 25 781.5 2 12.39 211.01 4.87 4.99 28 601.5 14 22.73 37.17 30 786.5 2 32.10 216.00 4.86 5.00May 3 606.5 14 42.44 42.03 Nov. 4 791.5 2 51.82 221.00 4.85 5.01 8 611.5 15 02.15 46.88 9 796.5 3 11.53 226.01 4.83 5.03 13 616.5 15 21.86 51.71 14 801.5 3 31.24 231.04 4.82 5.03 18 621.5 15 41.58 56.53 19 806.5 3 50.96 236.07 4.81 5.05 23 626.5 16 01.29 61.34 24 811.5 4 10.67 241.12 4.81 5.06 28 631.5 16 21.00 66.15 29 816.5 4 30.38 246.18 4.79 5.07Jun. 2 636.5 16 40.72 70.94 Dec. 4 821.5 4 50.09 251.25 4.79 5.08 7 641.5 17 00.43 75.73 9 826.5 5 09.81 256.33 4.78 5.08 12 646.5 17 20.14 80.51 14 831.5 5 29.52 261.41 4.78 5.08 17 651.5 17 39.85 85.29 19 836.5 5 49.23 266.49 4.77 5.09 22 656.5 17 59.57 90.06 24 841.5 6 08.95 271.58 4.77 5.10 27 661.5 18 19.28 94.83 29 846.5 6 28.66 276.68 4.77

The precession in longitude from 2000.0 to 2019.0 is +0.27° and from 2000.0 to 1950.0 is –0.70°.

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114 Astronomical and Physical Constants BAA Handbook 2019

ASTRONOMICAL AND PHYSICAL CONSTANTSGeneral: Gaussian gravitational constant 0.01720209895Astronomical unit (au) 149,597,870,700 metresSpeed of light in vacuo 299,792.458 km s–1

Dynamical form–factor J2 for the Earth 0.001082636Product of gravitational constant and mass of the Earth 398,600.5 km3 s–2

Earth–Moon mass ratio 81.3006Moon’s sidereal mean motion 2.661699489x10–6 radians s–1 = 0.5490149294" s–1

Obliquity of the ecliptic (2000) 23° 26' 21.448"Constant of nutation in obliquity (2000) 9.2052331"Solar parallax 8.794143"Light–time for unit distance 499.004784 s = 0.005775518 dConstant of aberration 20.49551"Mean distance Earth to Moon 384,400 kmConstant of sine Moon’s parallax 3422.451"Lunar inequality 6.43987"Parallactic inequality 124.986"Length of the year: Tropical (equinox to equinox) 365.24219d

Sidereal (fixed star to fixed star) 365.25636d

Anomalistic (apse to apse) 365.25964d

Eclipse (Moon’s node to Moon’s node) 346.62003d

Gaussian (Kepler’s law for a = 1) 365.25690d

Length of the month: Tropical (equinox to equinox) 27.32158d

Sidereal (fixed star to fixed star) 27.32166d

Anomalistic (apse to apse) 27.55455d

Draconic (node to node) 27.21222d

Synodic (New Moon to New Moon) 29.53059d

Length of the day: Mean solar day 24h 03m 56.555s = 1.00273791d mean sidereal time Mean sidereal day 23h 56m 04.091s = 0.99726957d mean solar time Sidereal rotation period of the Earth 23h 56m 04.099s = 0.99726966d mean solar timeSolar radiation: Solar constant 1.366 x 103 J m–2 s–1

Radiation emitted 3.84 x 1026 J s–1

Radiation emittance at surface 6.32 x 107 J m–2 s–1

Total internal radiant energy 2.8 x 1040 J Radiation emitted per unit mass 1.932 x 10–4 J s–1 kg–1

Visual absolute magnitude (Mv) +4.82 Colour indices (B–V, U–B) +0.65, +0.19 Spectral type G2V Effective temperature 5,800 KConversion factors: Light–year (ly) 9.4607 x 1012 km = 63,240 au = 0.30660 pc Parsec (pc) 30.857 x 1012 km = 206,265 au = 3.2616 ly

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BAA Handbook 2019 Astronomical and Physical Constants & Greek Alphabet 115

The Galaxy: Pole of galactic plane (2000) 12h 51m 26.28s, δ +27° 07' 42.0" Point of zero longitude (2000) 17h 45m 37.22s, δ –28° 56' 10.2" Galactic Longitude of North Celestial Pole (2000) 122.93° Mass 1.1 x 1011 solar masses = 2.2 x 1041 kg Average density 0.1 solar mass pc–3 = 7 x 10–21 kg m–3

Diameter 25,000 pc Thickness 4,000 pc Distance of Sun from centre 8,200 pc Distance of Sun above galactic plane 24 ±6 pc Solar apex (2000) (from radio astronomy) RA 18h 03.8m , Dec. 30° 00' Solar motion (from bright stars) 19.7 km s–1

Period of revolution of Sun about centre 2.2 x 108 yrFigure of the Earth: Equatorial radius 6,378,136.6 m Polar radius 6,356,751.9 m Flattening 0.0033528197 * ρ sin φ' = S sin φ, ρ cos φ' = C cos φ where: S = 0.99497418 – 0.00167082 cos 2φ +10–8 (210 cos 4φ + 15.7 h) C = 1.00167997 – 0.00168208 cos 2φ +10–8 (212 cos 4φ + 15.7 h) ρ = 0.99832707 + 0.00167644 cos 2φ –10–8 (352 cos 4φ – 15.7 h) + 10–8 cos 6φ tan φ' = [0.9933054 + (0.11 x 10–8 h)] tan φ φ – φ' = 692.74" sin 2φ – 1.16" sin 4φ 1° of latitude = [111.1333 – 0.5598 cos 2 φ + 0.0012 cos 4φ] km 1° of longitude = [111.4133 cos φ – 0.0935 cos 3 φ + 0.0001 cos 5φ] km Acceleration due to gravity g = 9.780310 [1 + 0.00530239 sin2φ – 0.00000587 sin2 2φ – (31.55 x 10–8) h] m s–2

Length of seconds pendulum l = [0.9935769 – 0.0026272 cos 2φ + 0.0000029 cos 4φ – (3133 x 10–10) h] m

Constant of gravitation 6.67428 x 10–11 kg–1 m3 s–2

Centennial general precession p = 5028.796195" + 2.2108696" T†_______________________________________________________________________* φ = Geographic or geodetic latitude ρ = Geocentric distance in equatorial radii φ' = Geocentric latitude h = Height in metres† T = Time measured in Julian centuries from J2000.0

GREEK ALPHABET

α alpha β beta γ gamma δ delta ε epsilon ζ zeta η eta θ theta ι iota κ kappa λ lamda μ mu ν nu ξ xi ο omicron π pi ρ rho σ sigma τ tau υ upsilon φ phi χ chi ψ psi ω omega

ASTRONOMICAL AND PHYSICAL CONSTANTS

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116 Acknowledgements & Errata BAA Handbook 2019

ERRATAHandbook 2018

p.25 Apsides - Perigee and Apogee headings are transposedp.26 Lunar Librations - Months not aligned correctly to dates columnp.34-39 Illumination of moon measurement should be "%"p.101 Algol Primary Minima times had a date error propogated through several dates. (see online version for corrections)p.108 delta Orionis should have Declination '-00 17 12' not '+00 17 12'

ACKNOWLEDGEMENTSThe Handbook would not be possible without the work of its many data contributors : Andrew Sinclair contributed the diagrams showing the visibility of planets and their appearances and also data and diagrams for Saturn's satellites. Barry Leggett supplied data for Jovian satellite eclipses and transits. Des Loughney provided heliocentric times of primary minima of variable stars. Fred Espenak (previously of the NASA/Goddard Space Flight Center) for his Eclipse charts. John Isles contributed the data on Mira stars. John Mason provided the meteor data. John Toone provided data on active galaxies and with Gary Poyner, provided data for variable stars and for the variable star of the year. Tracie L. Heywood supplied 2016 RS Canum Venaticorum light curve. Nick James provided data on comets. Ken Hall provided lunar libration data. Richard Miles provided data for asteroids, near–earth objects, trans–neptunian and dwarf planets, and diagrams for Pluto. Asteroid Favourable Observing Opportunities data were prepared by him, using data from the MPCORB database by Brian D. Warner; Alan W. Harris (MoreData! Inc.); and Petr Pravec (Astronomical Institute, Ondrejov, Czech Republic). Richard Kaye provided the System III Jupiter data, using a program written by himself. Robert Mackenzie provided the start dates for Carrington rotations. Susan Stewart of the United States Naval Observatory provided the bright stars positional data. Tim Haymes provided lunar occultation data and, with Edwin Goffin and Eberhard Riedel (International Occultation Timing Association), the tables and maps for asteroid occultations and grazing lunar occultations. Mike Kretlow for use of his asteroid and TNO database of current predictions. Steve Preston for his global updates on asteroidoccultations.com Tony Evans provided data for Mercury, Venus and Mars. William Thuillot (Institut de Mécanique Céleste et de Calcul des Ephémérides) supplied the diagrams of Jupiter’s satellites. Xavier Jubier Transit of Mercury charts and data.

Contributors have checked their own and others’ contributions and their comments have greatly improved the Handbook. The Editor gratefully acknowledges contributors’ support in answering any queries, and the many proof readers for their assistance. Any data not mentioned above have been provided by the Computing Section.

STEVE HARVEY Director

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The British Astronomical AssociationThe British Astronomical Association was founded in 1890 and now has about 3,000 members. Its leading features are:

Membership –Open to all persons interested in astronomy.

Objectives –(1) The organisation of observers, including those using small telescopes or binoculars, for mutual help. (2) The analysis and publication of observations.(3) The circulation of current astronomical information.(4) The encouragement of a popular interest in astronomy.

Methods –(1) The organisation of members in sections under experienced directors.(2) The publication of a Journal, Newsletters, a Handbook, Circulars and Bulletins.(3) The holding of meetings.(4) The maintenance of a collection of astronomical instruments for loan to members.(5) The affiliation of schools and societies.

Annual Subscriptions These are due August 1 each year. Current rates are available from the Office.

MEETINGS

Meetings are held at approximately monthly intervals, excluding July and August. Many are in London on either Wednesdays (starting at 17.30) or Saturdays (starting at 14.30). Meetings are also held at venues around the country. A very popular weekend meeting is held annually near Winchester in the Spring, along with a Summer Meeting or Exhibition. Back–to–Basics meetings for beginners are held outside London each year, usually in March and October. Observers’ workshops are also held twice per year. Many observing sections hold meetings every few years, some annually. Full details of the current programme are available from the office and the website.

PUBLICATIONS

The principal publications are the Journal and the Handbook. In addition, e–mailed bulletins, paper circulars and section newsletters are available to members.The Journal is published six times a year. It contains reports of meetings, reports of the sections, papers, reviews, letters, images and notes on current astronomical news. The complete set of Journals from 1890 is available on DVD.Occasional longer Memoirs containing detailed section reports. This Handbook, prepared by the Computing Section, is published annually.The e–bulletins/Circulars give early information on new and predicted events such as planetary phenomena and the discovery of novae and comets. The complete set of Circulars is available on CD.

REGISTERED OFFICE

The Registered Office of the Association is at Burlington House, Piccadilly, London, W1J 0DU.Email: [email protected] 020 7734 4145. Hours are 09.00 to 17.00, Monday to Friday.

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Printed by Berforts South West Ltd. +44 (0)1424 722733

The BAA on the InternetBAA Home Page

http://britastro.org

This website contains information about theBAA and how to become a member; it gives details

about the meetings, publications and merchandise for sale.There is a “members only” area, plus links to pages

maintained by the Observing Sections.You can find tutorials, news items, data on new comets,

asteroid occultations and other topical events,plus photo galleries and links to many other sources

of astronomical information.

BAA Computing Section

http://britastro.org/computing

This website complements the Handbook by providing extra material for which there is not room in the Handbook.

This includes : charts for many minor planets, calculational forms,

graphical applications such as what is observable at any time and positions of satellites of major planets.

Constant data that do not need to be printed every year in the Handbook together with links to other websites.

BAA Journal

http://britastro.org/journal