The Official Online Astronomy Society Guide to Beginning ... · Beginners Guide Starting Astronomy There are many reviews on beginning astronomy, good books for beginners out there,

Copyright © 2012 Online Astronomy Society all rights reserved

The Official

Online Astronomy Society

Guide to

Beginning

Astronomy

By

Alastair Leith


Contents Online Astronomy Society ...................................................................................................................... 3

Beginners Guide ...................................................................................................................................... 3

Starting Astronomy ............................................................................................................................. 3

So you want to take up astronomy do you? ....................................................................................... 3

Binoculars ........................................................................................................................................... 3

What will binoculars show? .................................................................................................................. 4

Learning the constellations ............................................................................................................... 4

A refracting telescope ....................................................................................................................... 7

Reflecting telescope .......................................................................................................................... 7

Mounts .............................................................................................................................................. 9

Suggested Projects ............................................................................................................................ 11

Observe Moon .............................................................................................................................. 11

Solar Project work ......................................................................................................................... 11

Charting planetary movement ...................................................................................................... 12

Taking pictures of the stars ........................................................................................................... 12

Maintenance of Kit ............................................................................................................................ 17

Conclusion ............................................................................................................................................. 17

Further Reading ................................................................................................................................ 18

Sky Charts .......................................................................................................................................... 19

January Sky .................................................................................................................................... 19

February sky .................................................................................................................................. 20

March Sky ...................................................................................................................................... 21

April Sky......................................................................................................................................... 22

May Sky ......................................................................................................................................... 23

June Sky ......................................................................................................................................... 24

July Sky .......................................................................................................................................... 25

August Sky ..................................................................................................................................... 26

September Sky .............................................................................................................................. 27

October Sky ................................................................................................................................... 28

November Sky ............................................................................................................................... 29

December Sky ............................................................................................................................... 30


Online Astronomy Society

Beginners Guide

Starting Astronomy There are many reviews on beginning astronomy, good books for beginners out there, but I thought

it was time the Online Astronomy Society had its own booklet on starting out

Astronomy has never been more popular as a science than it is now. With advocates to the science

being made more prominent with the likes of the BBC Stargazing Live, astronomy has never been

more accessible or affordable a subject to follow, with more ordinary people than ever performing

work of scientific value.

I have wanted for some time to write a guide for beginners which is practical, based on experience

and brings the pathway forward to the 21st Century.

Sir Patrick Moore has long advised people to start with the naked eye and binoculars and learn the

sky. Though I don’t necessarily agree with his advice on telescopes, that anything below 3inches for

a refractor or 6inches for a reflector is not much use for serious work. Define what serious work is?

Serious work is not the issue for the beginner either, enjoyment and learning is. So let’s begin.

So you want to take up astronomy do you? Well first off, let’s not go rushing off to buy the latest and biggest telescope on the market. That’s

like buying a car before you can drive. Simply take time out, buy or borrow a cheap pair of binoculars

and get to know the sky. Starting first with the naked eye, get your bearings. Appreciate the layout

of the sky and the constellations. I recommend a reasonable pocket sized handbook for this, red

torch and a pair of binoculars.

Binoculars

Ideal magnification for binoculars should be 7x50 or 10x50

What do we mean by 10x50 though?

Binoculars should be light and easy

to hold. Anything over 10x50 they

will be too heavy for long periods of

use.


The 10 is the magnification of the binoculars, the 50 is the diameter of the binocular objectives (the

larger lenses you see). So a pair of 10x50’s will be 10x magnification, and 50mm diameter. Which

might not sound a lot but it’s ideal for getting to know the sky and learning the stars. Binoculars

nowadays are often very cheap, anything from £10 upwards will buy you a decent pair. Plus if your

interest is short lived they can be used for other purposes.

What will binoculars show?

The obvious things are craters of the Moon, however you will also see

Jupiter and its Moons

Andromeda Galaxy

M33 another galaxy, face on. (Excellent conditions needed!)

M13 a globular cluster in Hercules. (Reasonable conditions needed)

M42 the Orion nebula.

Learning the constellations

Generally the easiest constellations which many won’t fail to recognise are:

Ursa Major, the great bear, this is visible ALL year round from Northern Latitudes and is key for

identifying the pole star

Ursa Major is also known as the Big Dipper, or the frying pan for obvious reasons. You can see it

highlighted above.

This constellation in itself has many interesting objects which you can come back and view later.

However here is what I suggest. Familiarise yourself with the constellation, get to recognise it, it may

very well be that due to light pollution that it’s the only one you can see clearly. While getting

familiar with the constellation why not take time out and learn the star names.

Learning star names will not only

help you better appreciate the

constellations but it’s great at

parties when you can name stars

people pointed to!


Once you have learned the constellation, and the names of the main stars in it, it is now time to

investigate what is of interest within. Many of the objects listed below are visible only through a

small to medium sized telescope. We will discuss telescopes later in this guide.

You can also see from this chart that The Plough extends much further to the remainder of the Big

Bear. And meets other constellations where you can begin to learn.

One thing I did as a kid was I stood out there with a pencil drawing dots of other stars around the

constellation I had learned. Using a star atlas I referenced these and used this as a means of

identifying another constellation and repeating the process.

Often the best time to be doing this is in the winter/ autumn time when the skies are darker and

clearer, it is also when one of the most celebrated constellations is in the night sky, Orion.


The purpose of this guide is not to reinvent the wheel in terms of astronomy guides however the

above pointers should help you to get going

Orion is impossible to miss even as a

complete beginner, I know as its one

of the first I recognised. I often call it

the “Bow Tie! for obvious reasons.

Not only easily recognisable but

contains some interesting objects.

Betelgeuse for example is a red

giant we expect to die at any time.

The star is the only one other than

our own Sun which can be resolved

as a disc. (by professional

telescopes). It would also swallow

up most of our solar system. As the

sun will do when it dies

M42 is the Orion nebula which can

even be see with the naked eye! A

fantastic binocular object that is

easily seen.


Once you have learned many of the constellations, and you’re still keen to keep going, it is

worth investing in a small telescope. A refractor is likely to give you less issue with mirrors

or collimation; however the pros and cons of both will be discussed.

Firstly, what is the difference?

A refracting telescope

So a refracting telescope is a long tube containing a large objective lens and an eyepiece

Reflecting telescope


There is more than one type of reflecting telescope but the most common beginner’s

telescope; the Newtonian will be discussed here.

Light collects in the bottom of the tube, and is reflected to the secondary mirror then to the

eyepiece. These telescopes are usually intrinsically larger than refractors and are generally

better suited to deep sky observing than refractors which by and large are better suited to

planetary, lunar, and solar work (NEVER LOOK DIRECTLY AT THE SUN WITH ANY TELESCOPE,

IT WILL BLIND YOU!).

Which to get?

Both have their pros and cons, my personal favourite are to start with a refractor. Main

reason being is though it has a low aperture; it suffers fewer of the problems a reflector can

have like collimation issues (see later) and dirty mirrors. However beyond the planets and

the Moon it has more limited ability with deep sky objects (this does NOT mean you can’t

see any, just means more limited).

Reflectors, although they have the potential of allowing you to view more due to having a

greater light gathering capability (larger mirror in other words), they do suffer problems

with mirror alignment and with mirrors needing to be re silvered after a while. The former

issue with the correct guidance from a local astronomy society will be quickly eradicated.

Pit holes to avoid.

High street shops are often the worse place to get a telescope from, especially refractors.

They will often sell small low grade telescopes in fancy packing promising the earth in

magnification. Higher magnification is NOT always the best thing. However there is another

pitfall to look out for

You will often see refracting telescopes with objectives stopped down with a plastic ring

Stopping Ring

Objective


The reason they do this is the central lens is better quality than the outer, so rather than cut

it out, they make the telescope look bigger by covering the lesser part over with a ring, a

dirtier trick is they will often place this ring inside, not outside the objective selling it with

the larger diameter advertised.

Mounts

Generally it can be argued there are two types,

a) Altazimuth

b) Equatorial

Both have their advantages and disadvantages.

Altazimuth Mouth: Probably among the most

common available on the market and a favourite

with beginners. Here is a typical one fitted with a

star diagonal and a finder. A star diagonal is useful

for not having to squat at the eyepiece. The mount

just moves left right, up and down both motions

need to be manually adjusted by the observer. This

is a point and look setup, not really suitable for

taking photos.

Equatorial mount is more complex.

The weights are needed to balance

the telescope. The movement is this

time in line with the earth’s rotation

so the mount needs to be polar

aligned. The telescope can only

move in RA (East to west) or

Declination (up and down), can be a

bit fiddly for an absolute beginner.

However, if setup correctly, motors

can be added making it suitable for

taking pictures.


Fork Mount

Seen mainly with another kind of telescope we have not so much discussed here, the

Schmitt Cassegrain Telescope. We will only briefly touch on it here.

There are other factors to consider when buying a telescope, but usually before making the

final decision, its best to venture to a local astronomy society to ask advice there, even try

out different telescopes to see what is best. Don’t forget, you’re never stuck with what you

buy, you can always upgrade to better later, this is the game we play in astronomy!

Where too from here?

It is definitely worth getting to meet other like-minded people. A local astronomy society

often has a mixture of like-minded people who are able to advise you on how best to use

your equipment and how to get to the next level. The Online Astronomy Society also caters

for beginners to intermediate with members more than happy to help you develop.

What happens once I have learned all the constellations and seen all I can with the

equipment I have?

It is likely then you will want to consider a specialism, and there are plenty you can get

involved with, some giving you the opportunity to do some real science.

This is not the place to be discussing other areas in depth but if you plug the below

keywords into Google they will point you in the right direction

Similar to the author’s setup, the

telescope you can see sits on a

tripod but is mounted in a wedge

which is the same as the observers

latitude. The idea is this tilts the

telescope towards the direction of

the pole star. It is closely related to

an Altazimuth; however that former

is not polar aligned.


Variable/ Double Stars

Lunar Observation

Planetary Observation

Solar Observation (never directly with a telescope though).

Astrometry (not many people do this)

Spectroscopy (or this)

Interesting Projects to carry out

Observing the Movement of Jupiter’s Moons

This can be done with ANY small telescope, see if you can plot Jupiter and its Moons over a

period of a few nights; it’s interesting to watch them move. Any astronomy magazine will

assist you in naming them.

Suggested Projects

Observe Moon

See if you can make detailed observations of the Moon. Even two half-moons will never

have the same detail due to the way the Sunlight hits the moon.

Solar Project work

I have mentioned more than once and will do so again, NEVER OBSERVE THE SUN DIRECTLY

WITH ANY TELESCOPE, YOU WILL BLIND YOURSELF. I make no apology for mentioning it

again here either. However if you are able to, use a refracting telescope, NOT a reflecting

telescope to project the Suns image onto a piece of paper.

You will be able to see what we call a white light image of the Sun


An interesting project could be to plot the movement of the sunspots across the Suns disc

over a period of a few days. Please keep in mind two things if you’re going to do this.

a) NEVER point the telescope at the Sun for too long, you will damage it.

b) NEVER use a solar filter for the EP even if it came with the telescope.

Charting planetary movement

Try observing, sketching or imaging surface details of Jupiter or Mars over a few hours when

either are up each night. You will notice that due to the rapid rotation of these heavenly

bodies the surface detail changes quite often, enough to notice if you took a picture or

made a sketch every 45 minutes or so!

Taking pictures of the stars

We have tutorials on the DVD about doing this, but it’s definitely worth mentioning this

here. This is also the first thing which attracts beginners to astronomy. I admit that although

I too have been bitten by the bug, it always in my opinion adds to the value if you know

what your images are and the purpose to it rather than just taking pretty pictures. I should

From this it is possible to identify

Sunspots on the Sun. Sunspots are

cooler areas of the Sun caused by

magnetic fields. This picture is

courtesy of Richard Bailey.

Solar Sketch made using the above

method by Mick Murphy, Ireland.

This chap learnt for Online AS how

to do solar projections.


also mention that the beginner might want to know why to bother taking pictures of the

Moon or the Orion nebula. My answer is well when you go on holiday, why bother taking

pictures of famous landmarks when others have already done so. The answer is because

they are YOUR pictures, and this is where the added value comes in.

As much as I have resisted imaging as a hobby as I do not class it as amateur astronomy per

say (its more astrophotography), some interesting science can still be carried out. So I am

going to say a few words here on this in terms of kit to you.

First off, there is no need to blow the household budget, with a little time and patience you

can take half decent shots of the Moon and the planets, and there are number of articles on

this.

Serious astrophotographers will use expensive DSLR’s and cameras, you don’t have to.

For starters, some webcams can be used to take very decent pictures of the Moon and the

planets.

The Toucam Pro 2+ webcam is widely used by amateur astronomers to picture the Moon

and Planets

The trick is to unscrew the lens and

screw in a 1.25 inch nose adapter


This then fits down the eyepiece barrel enabling you to capture images with it. Please see

the tutorials mentioned on the DVD if you’re unsure how to do this.

Webcams are particularly useful for

Imaging the Moon

Venus, Mars, Jupiter, Saturn, and the Moon.

You MIGHT get some of the Orion Nebula with it, however beyond that you will need to use

a DSLR cameras as described in the tutorials on this DVD. The author uses a Canon DSLR

1000D camera, which is inexpensive, compared to other models and can have what we call

a t-ring and adapter added to make it suitable for astronomy

The lens will unattach from the body (consult manual if unsure how to do this)

Here is one with a filter

fitted on the end

You can see the authors setup here

complete with the t adapter and the

screen in nose piece


A few hints if doing this

Ensure that whatever you affix to the adapter, including the cap, the nosepiece, even filters

or Barlow’s are clean and dust free before fitting it either to your camera or the telescope.

You don’t want dust particles or such like messing up the sensor of the camera or falling

down the tube of your telescope. A little OCD of me but these are things I try to avoid.

Puritans would suggest resting the camera as below until needed.

Exercise caution here in that you

don’t want any dust of debris falling

into the camera as you do this.

The cameras now complete with the

adapter fitted. Note the lens cap is

kept on. This is to prevent any dust

or flies from wandering in until

you’re ready to use it.

Small measures like this can keep

dust and other mites from

appearing on the images you take!


Once ready, the camera is ready to put into the rear end of the telescope, where you

normally put the eyepiece. Ensure before you proceed that the camera is NOT too heavy for

your mount.

The reason too why this model is popular is due to the live view of the camera, for many it’s

a lifeline for those who work without a laptop

There is much more left to cover regarding the use of the DSLR for astrophotography,

indeed it is an art form in itself.

However things to note with using the DSLR are it’s only really ideal for imaging the Moon

and deep sky objects. If it’s the planets you desire, then I would suggest keeping with your

toucam, so this is not and either or game. You will need both.

Also things which have caught me out when using my camera are flat batteries, so ensure

you have spares or that what you use is fully charged! Ensure too if you’re working from Live

View that the SD card has been inserted back in (see below)

Live view of the camera (the big

screen can be really useful in

astronomy)

This is a view showing the authors 8

Gig SD card which the camera will

store images on if not connected to

laptop


Maintenance of Kit The first temptation of any beginner is to keep the kit sparkling clean. The advice is DON’T clean

anything unless you REALLY need to. How to clean kit is a subject for elsewhere however for things

like DSLR cameras it really is better to take it to a specialist for cleaning.

Removing grit off eyepieces should be done using a blower to blow the grit off, followed by a camel

brush to gently wipe off if that fails. The important thing is to keep your kit in a case where you can

get to it easily and will keep your kit clean and dry when not in use.

Conclusion I hope this mini guide has been of some use to the beginner, in writing it I have tried to keep

it simple and to the point. However allowing for enough for the beginner to develop with

this guide and move forward with their interest.

In writing this I have tried to base it on mine and others experiences rather than any book.

Nothing written above has been based on anything other than hard won knowledge.

I would like to add that while astronomy is a very rewarding interest to follow it is not

without its woes and challenges. Light Pollution is a constant which hampers most amateur

astronomers at some point or other. In many cases we learn to adapt using filters and such

like. Weather cannot of course be helped. Then of course there are conditions which effect

the seeing of the sky when it’s clear. Just because a sky may be blue with the potential of

going clear it does not necessarily mean the seeing conditions are going to be great. You will

notice the difference if you see fewer stars and more of an orange glow. If it is very humid

The live view indicator is used to

show the level of the battery

The battery compartment at the

rear. This may vary from model to

model


when you setup it is likely only going to be good for the Moon and Planets (with a lot of

possible turbulence even then).

Astronomy also has the potential of being extremely expensive if you are not careful, so

shop around and know what you want and what you want to do with it.

Star charts are going to be the next resource you will likely want from this guide; I have

included them at the end. Also a reading list, these books are not recommended to look

good and sit pretty on a bookshelf, they are texts which YOU will find invaluable on your

journey to becoming an amateur astronomer

Further Reading Turn Left at Orion

Invaluable resource for knowing what is up there and how it will look through the telescope.

One of the few resources which completely ignores the camera and looks at what you can

SEE with the eye down the eyepiece

Collins Gem Star Atlas,

No amateur astronomer should be without this. An ace publication, I still use mine to this

day, its over 20 years old now!

For a general introduction to the stars and planets I recommend

Wonders of the universe – Professor Brian Cox

Wonders of the Solar System – Professor Brian Cox.

Societies

www.onlineastronomysociety.com

Free to join and also has a forum, offers a magazine, webinars and tutorials for paid

members. £15 per year to join.

Society Popular Astronomy

British Astronomical Association

HantsAstro

Magazines

Become a premium member of the Online Astronomy Society and receive our magazine,

fully downloadable with all the information you will need for your nights viewing.

http://www.onlineastronomysociety.com/


There is also the Sky at Night Magazine

Astronomy Now

Sky Charts Provided courtesy of Ninian Boyle of www.astronomyknowhow.com

January Sky

http://www.astronomyknowhow.com/


February sky


March Sky


April Sky


May Sky


June Sky


July Sky


August Sky


September Sky


October Sky


November Sky


December Sky

Documents

The Official Online Astronomy Society Guide to Beginning ... · Beginners Guide Starting Astronomy There are many reviews on beginning astronomy, good books for beginners out there,