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EXTANT LIFE ON MARS? THE MARS SOCIETY ICY SCIENCE PUBLICATION: WWW.ICYSCIENCE.COM: WINTER 2013/14

Astro Nerds Astronomy Ezine March 2015

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Spring is beckoning, the days are getting longer, for some of us that is bad news, however spring and summer still brings us many delights in the night sky. We have are usual features this month, with the night sky, gallery and part 2 of astrophotography without a telescope. For those who are active on social media many would have seen the stunning images from Jaspal Chadha, he talks to us about his journey into astronomy, and we do include some of his stunning images.

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Page 1: Astro Nerds Astronomy Ezine  March 2015

EXTANT LIFE ON MARS?THE MARS SOCIETY

ICY SCIENCE PUBLICATION: WWW.ICYSCIENCE.COM: WINTER 2013/14

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Welcome to March Edtion Of Astro Nerds

Spring is beckoning, the days are getting longer, for some of us that is bad news, however spring and summer

still brings us many delights in the night sky.

We have are usual features this month, with the night sky, gallery and part 2 of astrophotography without a

telescope. For those who are active on social media many would have seen the stunning images from Jaspal

Chadha, he talks to us about his journey into astronomy, and we do include some of his stunning images.

We have also updated the website www.icyscience.com with some new features and revamped older ones.

The International Space Station (ISS) page has gone through improvements, with a live news feed, live video

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links and a location map via the ESA. A new feature

on the website are news updates, articles and video

on Saturn’s moon , Titan. We are also at the start-

ing point of a new project. The project is to bring a

small public observatory to the Wolds of Yorkshire,

check the website for details.

Editor: David Bood

ENJOY....

contents

6. Solar filaments and prominences18. PT 2 Astrophotography Without a

Telescope30. Look Up, A guide to the night sky38. Reader Profile, Jaspal Chadha

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Solar filaments and prominences – by Andy

Devey

Filaments are large regions of very dense,

cool gas, held in place by magnetic fields

they are like curtains of suspended gas. They

usually appear long and thin above the chro-

mosphere. It is because they are cooler than

their surroundings that they appear dark.

But if they appear on the “edge” of the Sun,

they appear brighter than the dark outer

space behind them. In that case we call them

prominences. Prominences and filaments are

really the same thing, but they look bright or

dark depending on what is in the picture’s

background.

Occasionally the Sun will treat us to some

of these features that are monstrous in their

dimensions. During February 2015 one such

feature was over 1,000,000 km long a dis-

tance equivalent to travelling from the Earth

to the Moon, back to Earth and half way back

to the Moon again.

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This is a H-alpha picture sometimes a negative image can reveal hidden detail and this extremely long feature

is now a filament and prominence as it traverses the western limb.

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Comparison of positive and negative images.

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To obtain the dimensions of these structures we can superimpose a “solar

ruler” onto our images to scale the individual features.

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Negative image from 11 February and positive and negative from 9

February 2015.

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9 February this was my first attempt to measure it.

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Filaments can last for a few weeks or months and occupy magnetic inversion lines. The gas in a filament

will eventually move to a different layer in the Sun and will no longer be visible in an image of the chromo-

sphere. But at the same time, other gas may move into the chromosphere and create a new filament some-

place else. The birth and death of filaments is a mystery and the subject of ongoing study by solar scientists.

Sometimes we may be lucky enough to image these huge structures lifting off when they become unstable

and I have caught numerous extreme examples of this phenomenon that are posted on my website. Two

notable examples are 1 Prominence lift off:

http://cdn.astrobin.com/images/9fd153a0-8cdb-4209-be59-4c9cb9f06ece.gif

2 Filament lift off:

http://cdn.astrobin.com/images/5610/2014/78ec9db9-e851-4988-91dd-c356605ee102.gif

http://thesolarexplorer.net/

BY ANDREW DEVEY

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PT 2 Astrophotography Without a Telescope- Thomas J. Nelsonwww.randombio.com

mounts

Using an ordinary tripod, how long can you expose before star trailing

becomes a problem? Trailing is influenced by four factors:

Time The longer you expose, the more trailing you will get.

Aperture The more light you can get onto your sensor, the shorter your

exposure can be.

Magnification With a 35-mm lens and a camera with a DX or APS-C

sensor, star trailing becomes objectionable after about 20 seconds. With

a 200-mm lens on the same camera, stars begin to change into streaks

after only 5 seconds.

Declination The amount of trailing per unit time depends on the cosine

of the angle from the celestial equator. In plain language, that means

if you point directly at the north or south pole, there will be no trail-

ing, and you will get the most trailing for objects on the equator. For

example, with a 200mm lens you can expose stars in Ursa Major for up

to 5 seconds, but the longest you can expose the Orion Nebula without

trailing is about 2 seconds.

There are several ways to deal with this:

Motorized mount Inexpensive motorized mounts made specifically for this purpose are available. As your magnification approaches that of a telescope,

getting more precise movement and aligning the mount with the Earth’s axis become more and more important. If you’re in the northern hemisphere, align-

ing it is done by pointing the axis of rotation of the mount toward Polaris. The more expensive German equatorial mounts used by amateur astronomers will

also work, but they aren’t needed at these levels of magnification, unless you want very long time exposures. Some people use a homemade device known

as a “barn-door mount.”

Motorized telescope mounts gradually become more inaccurate over time, and eventually need to be rebuilt or replaced. Most people get fed up with

doing this and buy an autoguider, which is a separate camera or section of a chip that locks on to a star and corrects the tracking of the mount by sending

correction signals back to the mount. If you buy a telescope mount, make sure it can accept an autoguider input.

Manual tracking If your tripod permits it, you can also rotate the camera manually, using a separate monocular with a reticle to keep the object centered.

Probably the least fun option, but it’s how they did it in the old days.

Stacking Take many short exposures and stack them using a free software package like Deep Sky Stacker. This works well, but it’s a little inconvenient,

because you might have to stack hundreds of frames. Stacking increases the signal and reduces the noise, and can produce excellent images. The trick is to

expose long enough that your signal is safely above the noise level of the camera, but not so long that the stars turn into streaks.

Increase the ISO This option increases the noise in your image, generally producing unsatisfactory results. However, if you have a high-end camera like a

Nikon D4, it may still be a good option.

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PT 2 Astrophotography Without a Telescope- Thomas J. Nelsonwww.randombio.com

There are several ways to deal with this:

Motorized mount Inexpensive motorized mounts made specifically for this purpose are available. As your magnification approaches that of a telescope,

getting more precise movement and aligning the mount with the Earth’s axis become more and more important. If you’re in the northern hemisphere, align-

ing it is done by pointing the axis of rotation of the mount toward Polaris. The more expensive German equatorial mounts used by amateur astronomers will

also work, but they aren’t needed at these levels of magnification, unless you want very long time exposures. Some people use a homemade device known

as a “barn-door mount.”

Motorized telescope mounts gradually become more inaccurate over time, and eventually need to be rebuilt or replaced. Most people get fed up with

doing this and buy an autoguider, which is a separate camera or section of a chip that locks on to a star and corrects the tracking of the mount by sending

correction signals back to the mount. If you buy a telescope mount, make sure it can accept an autoguider input.

Manual tracking If your tripod permits it, you can also rotate the camera manually, using a separate monocular with a reticle to keep the object centered.

Probably the least fun option, but it’s how they did it in the old days.

Stacking Take many short exposures and stack them using a free software package like Deep Sky Stacker. This works well, but it’s a little inconvenient,

because you might have to stack hundreds of frames. Stacking increases the signal and reduces the noise, and can produce excellent images. The trick is to

expose long enough that your signal is safely above the noise level of the camera, but not so long that the stars turn into streaks.

Increase the ISO This option increases the noise in your image, generally producing unsatisfactory results. However, if you have a high-end camera like a

Nikon D4, it may still be a good option.

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Use a faster lens Good option but expensive.

Fix it in the computer Small amounts of trail-

ing can be removed by deconvoluting the image.

This is the worst option of all, because it not

only increases the noise, it can create bad arti-

facts in the image.

Only take pictures of Polaris This works well, but

gets boring after awhile.

Make the image really small If you shrink the

image enough, they won’t notice the fact that

your stars are actually short dashes.

Give up Star trails are cool, too.

As mentioned above, trailing can also be caused

by zoom lenses zooming by themselves.

Nebulae (Added Sep 24, 2013)

I mentioned above that nebulas are ideal subjects for astrophotography

with a regular camera because they are so big. But what exactly do you need

to take good pictures of a nebula? Here’s a shopping list:

A motorized mount is essential, because you will be exposing for 5 minutes

to an hour.

At least one two-inch diameter narrow-band filter. Hydrogen-alpha (Hα)

filters and Oxygen-III (OIII) filters are good to start. (Watch out: some filters

marked as Hα are really long-pass filters and will give terrible results.)

A 52-48 mm step-down ring, plus a set of step-down rings if your lens is

something other than 52 mm in diameter.

A fast, sharp lens. If your lens isn’t sharp, the stars will be so big that they

will tend to cover up the nebula.

clear, dark sky.

A camera modified for infrared. Some people modify their own camera, but

there are many vendors who will do it for a fee. It’s a simple modification,

and the modified camera can usually still be used for regular photography.

If you save the parts it’s not difficult to convert it back.

For DSLRs, the newest bunch of cameras are preferred because they’re much

more sensitive. Since you’ll be using a narrow-band filter, Live View focusing

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Nebulae (Added Sep 24, 2013)

Image of a portion of the Milky Way in the constellation of Cygnus using filters. This image was made

without a telescope, using a Nikon D90 modified for infrared, and a CGEM motorized mount. The red

channel is a single 10-minute exposure with a Baader 7 nm H-alpha filter. The green and blue channels

are a single 10-minute exposure with a Celestron 8-nm OIII filter. Lens: Nikkor f/1.2 50 mm, set at f/2.0,

ISO 400, no guiding (Cropped and resized).

I mentioned above that nebulas are ideal subjects for astrophotography

with a regular camera because they are so big. But what exactly do you need

to take good pictures of a nebula? Here’s a shopping list:

A motorized mount is essential, because you will be exposing for 5 minutes

to an hour.

At least one two-inch diameter narrow-band filter. Hydrogen-alpha (Hα)

filters and Oxygen-III (OIII) filters are good to start. (Watch out: some filters

marked as Hα are really long-pass filters and will give terrible results.)

A 52-48 mm step-down ring, plus a set of step-down rings if your lens is

something other than 52 mm in diameter.

A fast, sharp lens. If your lens isn’t sharp, the stars will be so big that they

will tend to cover up the nebula.

clear, dark sky.

A camera modified for infrared. Some people modify their own camera, but

there are many vendors who will do it for a fee. It’s a simple modification,

and the modified camera can usually still be used for regular photography.

If you save the parts it’s not difficult to convert it back.

For DSLRs, the newest bunch of cameras are preferred because they’re much

more sensitive. Since you’ll be using a narrow-band filter, Live View focusing

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won’t work with the older cameras. You can still focus by trial and error,

but a more sensitive camera, like Nikon’s D7100 or the Canon equiva-

lent, will make the task much easier. Some nebulas are bright enough

that you can dispense with some of the above items. For example, I’ve

taken reasonably good pictures with a Hα narrowband filter of objects

that were only a few degrees away from the full moon (dispensing with

item no. 5). For a blue oxygen III filter, though, you need dark. A modi-

fied camera is only needed for Hα and SII, which are in the near-infra-

red. If you don’t want to risk modifying your camera, you can still take

great pictures of some nebulas with an unmodified camera, using an

OIII filter, but they will appear blue. Unfortunately, not all nebulas emit

blue radiation. Photographic lenses are ideal for wide-angle shots like

the photo of the nebulae in Cygnus shown above. This image combines

the nebulas around the star Sadr, which is the center of the “cross” in

Cygnus. The butterfly-shaped IC 1318 nebula in the center and the tiny

C-shaped Crescent Nebula (NGC 6888) above and to its right appear red.

The large white nebula at the lower left is the North America Nebula

(NGC 7000). Just above it is the Pelican Nebula. The white parenthe-

ses-shaped one at lower right is the Veil Nebula (IC 1340). No telescope

was used, but the camera was attached to a CGEM German equato-

rial mount. Compare this image with the image at the top of the page,

where the North America nebula is just a faint pink smudge super-

imposed on the Milky Way background. Without a filter, it is virtually

impossible to photograph the Veil nebula with a camera lens. With a

filter, you almost can’t miss it.

The sharpness of the lens makes a huge difference in pictures like this, because the stars are point sources. Don’t listen to people who tell you a sharp

lens is not necessary. I tried the same nebula on the same night with a f/1.8 35-mm lens, focused to perfection, and instead of sharp points, the stars

came out as big fuzzy blobs. So I switched to a manual f/1.2 50-mm lens. The trade-off with this particular lens is that near-infrared and blue don’t focus

to exactly the same point, so it’s necessary to re-focus when switching filters.

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The sharpness of the lens makes a huge difference in pictures like this, because the stars are point sources. Don’t listen to people who tell you a sharp

lens is not necessary. I tried the same nebula on the same night with a f/1.8 35-mm lens, focused to perfection, and instead of sharp points, the stars

came out as big fuzzy blobs. So I switched to a manual f/1.2 50-mm lens. The trade-off with this particular lens is that near-infrared and blue don’t focus

to exactly the same point, so it’s necessary to re-focus when switching filters.

What do filters do?

The purpose of filters is to reduce the amount of light coming from stars, making them smaller. Getting

the stars small prevents them from blocking the nebulas, which have much lower surface brightness than

stars. A filter also reduces the sky background, which is spread out over all wavelengths. Emission nebulas

emit most of their light in narrow emission lines corresponding to ionization of various elements. Since

nebulas are mostly hydrogen, this means that Hα usually gives the brightest signal.

Non-emission nebulas, like the Witch Head Nebula, are not helped by using filters.

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More advanced techniques

Some objects are so large that it’s virtually impossible to photograph them with a telescope. That’s where the power of telescope-free astronomy comes in. Most people are probably familiar with the gigantic Orion Nebula (see photo above),

but they might not realize that it’s surrounded by an even larger nebula called Barnard’s Loop (Sh2-276), which is over 12 times bigger, both in actual size and apparent size, with an angular size of almost 840 minutes of arc. That’s 28 times bigger

than the angular size of the Moon. Barnard’s Loop covers nearly 15% of the distance from the celestial equator to the pole. Yet despite its size, it is far too faint to be seen with the naked eye, or even through the eyepiece of a typical telescope.

At this scale, the entire Orion Nebula, which is about twice the apparent size of the moon, is only a small white blob in the center, and the Horsehead Nebula is a tiny dark blip near Alnitak (the leftmost of the three large stars in Orion’s belt).

Photographing Barnard’s Loop with a telescope would be like photographing the Empire State Building with a microscope. You could do it, and you’d certainly get better resolution and finer detail, but it would take weeks of exposing and pains-

takingly stitching images together. The image below took less than an hour to photograph, plus another ten or twenty minutes of computer processing time.

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More advanced techniques

Some objects are so large that it’s virtually impossible to photograph them with a telescope. That’s where the power of telescope-free astronomy comes in. Most people are probably familiar with the gigantic Orion Nebula (see photo above),

but they might not realize that it’s surrounded by an even larger nebula called Barnard’s Loop (Sh2-276), which is over 12 times bigger, both in actual size and apparent size, with an angular size of almost 840 minutes of arc. That’s 28 times bigger

than the angular size of the Moon. Barnard’s Loop covers nearly 15% of the distance from the celestial equator to the pole. Yet despite its size, it is far too faint to be seen with the naked eye, or even through the eyepiece of a typical telescope.

At this scale, the entire Orion Nebula, which is about twice the apparent size of the moon, is only a small white blob in the center, and the Horsehead Nebula is a tiny dark blip near Alnitak (the leftmost of the three large stars in Orion’s belt).

Photographing Barnard’s Loop with a telescope would be like photographing the Empire State Building with a microscope. You could do it, and you’d certainly get better resolution and finer detail, but it would take weeks of exposing and pains-

takingly stitching images together. The image below took less than an hour to photograph, plus another ten or twenty minutes of computer processing time.

Barnard’s Loop in Orion is 320 light years across and only 1300 light years away, so its angular size is 13.8 degrees. (Modified

D90 and 50-mm f/1.2 lens.) Compare this image with the one below from a monochrome CCD camera

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Here’s the equipment that was used for this image.

A DSLR partially modified for infrared, set at ISO 800.

CGEM motorized mount (aligned with Polaris using a polar scope).

2-inch H-alpha, 7 nm filter and a 52-48 mm step-down ring.

Nikkor 50 mm f/1.2 lens set at f/2.0.

A copy of Deep Sky Stacker.

Image processing software (Imal or equivalent) to adjust the contrast.

To make this image, I took 11 exposures of 5 minutes each with the Hα filter and 8 color exposures of

15 seconds with no filter. At f/2, with moderate levels of light pollution, you can only expose for 10-15

seconds before the the sky background starts to saturate the image sensor. If your lens is slower, you will

need proportionately longer exposures. Because Barnard’s loop is so faint, the H-alpha filter is essential

for blocking out the starlight. Almost nothing is visible through an O III filter; hydrogen is by far the stron-

gest signal, so you need a camera that can photograph the near-infrared wavelength of hydrogen. That

means either a modified DSLR or a specialized CCD astronomy camera.

In Deep Sky Stacker, make sure to load the color images first, or the software may get confused and make

the image completely red. The rule of thumb is: one second without a filter is equivalent to one minute

with a filter.

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Cooled astronomy cameras

Compare this image with the one below taken using a cooled astronomy camera (total exposure 40 min). CCD cameras are

more sensitive and have higher resolution than a DSLR. Images are smoother because of the greater pixel depth, but the

cameras are harder to use. Generally they’re controlled by a laptop computer through a USB, ethernet, or serial cable.

You can get comparable images with a DSLR, but it takes a lot longer. See linuxsetup137.html for details on setting up a CCD

camera. What an astronomy camera buys you is more efficient use of your limited observing time. Barnard’s Loop photographed

with the same Nikkor f/1.2 lens, but using a cooled astronomy camera instead of a DSLR. Left: Red=Hα, green=luminance

and blue=blue. Right=Halpha only. These images were taken on a night when lots of airplanes were flying around, so they

are crisscrossed with airplane trails. Nebulae are often shown in grayscale to make it easier to see the detail. Technically this

was a cooled CCD camera, but in this instance additional cooling was not actually necessary. It was so cold that when I set

the camera to −15C, instead of cooling down, the heater came on.

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Top Image: Barnard’s Loop Cropped, unresized image of Crescent Nebula (NGC 6888) taken with a Nikkor 50mm

f/1.2 lens without a telescope using a cooled CCD camera and filters. Red=Hα, Green and Blue = OIII. Notice how the

nebula is partially obscured by the stars. A telescope image would show more detail and the stars would be smaller,

while a DSLR image would be fuzzier and many of the fainter stars would be lost in the noise. (Contrast-stretched

and cropped to 1.46% of original area. CGEM motorized mount; total exposure 90 min.)

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Bottom Image: Veil nebula photographed with a 180 mm f/2.8 telephoto camera lens. Because the Veil Nebula is

so big, most telescopes can only capture part of it at a time, but it’s a perfect match for this lens. I used a cooled

monochrome CCD camera for this image. That allows you to re-focus after changing filters, which is necessary

with most camera lenses. The limiting factor here was the blue-green background from the Moon, which was out

while the picture was taken. I subtracted that from the image. Even so, it only took 20 minutes with each filter to

get this image. (Red = H-alpha filter; Green and blue = OIII filter. Not cropped, but contrast-stretched and resized.

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LOOK UP- A GUIDE TO THE NIGTHT SKY BY JOHN HARPER F.R.A.S

March, 2015 SKYNOTES

The Sun begins the month in the constellation of Aquarius but crosses the border into Pisces on the 12th

at around 21h. It is climbing steeply now and daylight increases rapidly. On March 20th 22h45, the Vernal

Equinox occurs, when the sun is directly overhead at the earth’s equator. The sun-earth distance at the time is

148,989,865 km. The astronomical season of spring begins and lasts for 92.74 days. If the earth had no atmo-

sphere, day and night at this time would be exactly equal all over the planet except at the poles, but due to

atmospheric refraction, this scenario occurs some days earlier.

March is the best month to observe the mysterious Zodiacal Light during evenings when the moon is not present

in the sky and you are well away from light pollution. Look towards the west when twilight has faded and you

should see a faint cone of light pointing southwards at a steep angle of 60°. This year, the best dates to observe

the zodiacal light are from the 7th to the 20th. The sun illuminating the disc of fine dust, which is the remnant

of solar system formation 4.5 thousand million years ago, causes this phenomenon.

THE MOON

The Moon is at perigee, its nearest to the earth, at 19h39 on the 19th, and at apogee, its furthest from

the earth, at 07h00 the 5th.

Full Moon is on the 5th around 18h06 amongst the faint stars of southern Leo.

Last Quarter Moon, is on March 13th at around 17h49 on the Ophiuchus/Sagittarius border

and is the lowest Last Quarter moon of the year.

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LOOK UP- A GUIDE TO THE NIGTHT SKY BY JOHN HARPER F.R.A.S

March, 2015 SKYNOTES

New Moon is on the 20th at 09h37,

just north of the intersection of the constella-

tions Cetus, Pisces and Aries, during which the

sun and moon are situated in this latter con-

stellation. ECLIPSE! (see below)

First Quarter takes place at

07h43 on March 27th in Gemini, in the vicin-

ity of the star Alhena (gamma Geminorum)

and is one of the highest First Quarter moons

of the year.

Earthshine, (the faint glow on the

night hemisphere of the moon caused by

reflected sunlight from the earth), may be seen

during the evenings on the dark hemisphere of

the waxing crescent from the 21st to the 26th,

and waning crescent from the 14th to the 19th.

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DEEP PARTIAL ECLIPSE OF THE SUN

This is one of the best deep partial eclipses visible from the UK since August 1999, which you will remem-

ber was total in the SW corner of the UK. The shadow of the moon travels mostly north-west-wards along

the north Atlantic, the Norwegian Sea and on towards the North Pole via the Arctic Ocean. There are two

landfalls only and these are the Faroe Islands and the sparsely inhabited Norwegian Svalbard Islands.

Interestingly the shadow of the moon leaves the earth in the vicinity of the North Pole as the sun is touch-

ing the horizon, having just risen after the long Arctic night. The reason for this is that although the Equinox

does not take place until 13 hours later, when theoretically the sun’s disc should be only half visible, refrac-

tion in the earth’s atmosphere causes the entire disc to be seen. Unfortunately at this time of the year, cloud

cover tends to be at its worst over the areas of totality.

From Scarborough the eclipse begins at 08h29, when a small notch on the upper limb of the sun marks the

appearance of the New Moon as it begins its crossing of the sun’s disc. The maximum phase is at 09h35,

at which time the sun’s altitude in the SE is 28°. At this time, over 90% of the sun’s diameter will be hidden

by the moon, and so observing the sun using the proper techniques of projection and special astronomi-

cal filters will allow you to see the sun at that moment as a thin crescent ‘lying on its back’. The appearance

from Scarborough is as good, if not better than, the August 11th eclipse of 1999. The moon continues its

eastward journey across the sun and leaves the solar disc at 10h44.

Here in Scarborough, I shall be at the Holbeck Clock Tower at the south end of The Esplanade (which affords

easy access) at 8.15 am, with a couple of specialised telescopes to enable people to observe the eclipse

safely. There will also be available a number of different types of solar filters for people to use. We hope the

weather is fine, on this last day of winter! All are welcome.

(see Safety Notes which follow these Skynotes!

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The Planets

Mercury is not easily visible during March as it moves towards its supe-

rior conjunction beyond the sun in April. However, if you scan the ESE

horizon at around 06h30 on the first few days of the month, you may

spot the elusive planet within 5° of the horizon, which must be clear of

all haze and obstructions

Venus, in the faint constellation of Aries, is a splendid evening object and

will be glimpsed from sunset onwards for three or more hours before

the planet sets. There is no mistaking Venus, the ‘Evening Star’, (known

to the ancients as Hesperus) as it shines as the brightest object in the

sky after the sun and the moon. A couple of days after the solar eclipse,

the moon will be seen as a thin crescent with ‘earthshine’ in the vicin-

ity of Venus. On the 22nd from 19h onwards, the crescent moon lies 4°

below and slightly to the left of Venus in the dusk sky.

At the beginning of March, Mars sets a couple of hours after the sun,

but the length of time the planet continues to be visible in the evening

sky diminishes, until by the end of the month it sets some 20 minutes

after 20h. The planet continues to move slowly eastwards in the con-

stellation of Pisces. On the 1st of the month, Venus may help you to

locate Mars as the two are comparatively close together in the fading

twilight around 19h; Mars is the much fainter, reddish tinged object,

lying just over 3° to the lower right of Venus. The ‘red planet’ is now

far away from the earth and in order to see details on its surface you

will require high magnification and a non-turbulent atmosphere, as it

is only 10° above the western horizon in the fading twilight. The very

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thin crescent moon, with earthshine, is close to Mars during the evening of the 21st,

when the planet is some 3° above the moon at that time and due west.

Jupiter continues to shine brightly and steadily high in the vault of heaven amongst

the faint stars of Cancer the Crab, just to the west of the constellation’s border with

Leo. However, at the end of March the giant planet is setting at 04h. During the month

the planet culminates (reaches its highest point in the south) just before midnight

in the late evening.

Remember to look for the four Galilean Satellites through firmly fixed binoculars as

they change position from night to night.

During the evening of the 2nd and 3rd of March, the broad gibbous, waxing moon

passes some 6° below Jupiter.

As March begins, Saturn rises at 01h30, but before midnight at the month’s end. The

‘ringed planet’ lies in the constellation of Scorpius, just over one degree from the

star Graffias (beta Scorpii). The northern surface of the ‘rings’, as seem from Earth,

continues to be displayed well. The planet reaches a stationary point in its eastward

motion on the 14th, where after, it begins to move retrograde towards the Libra

border, as earth begins to overtake the planet ‘on the inside lane’. On the morning

of the 12th, the gibbous waning moon may be seen approaching Saturn, which is

the bright star-like object 2° (four moon widths) to the lower left of the moon.

Saturn is admirably placed in its orbit for a good opportunity to see the northern

‘surface’ of the planet’s glorious ring system, even through a small telescope. In such

an instrument, which inverts the image, you may be able to spot Titan, the largest

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of the Saturnian moons as a faint ‘star’ to the right of the planet on the 4th to the 6th

and again from the 20th to the 22nd, and to the left of the planet from the 12th to the

14th and from the 28th to the 30th.

As the sky darkens on March 4th, around 19h30, use Venus to spot the remote planet

Uranus, which early next month will be far beyond the sun at conjunction. on the 4th,

the two objects are 10° above the western horizon, and if you turn your binoculars

towards Venus, you will see Uranus as a faint object just 5 minutes of arc to the lower

left of Venus (one sixth of a moon width). Both planets will be seen in the same field of

view in binoculars and also in telescopes at low power(to the upper right)

Neptune was in conjunction with the sun towards the end of last month and is too near

the glare of our nearest star to be seen.

Constellations visible in the south around midnight, mid-month, are as follows: Leo, the

western part of Virgo, Crater, and Hydra. The Plough (Big Dipper), which is part of the

constellation of Ursa Major, the Great Bear, is at the zenith, directly overhead.

Clocks go forward an hour in the morning of Sunday March 29th (and ends on Sunday

25th October)

All times are GMT 1° is one finger width at arm’s length.

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IMAGE CREDIT Jaspal ChadhaOpen Star Clusters M35 and NGC 2158

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Reader Profile:

Jaspal Chadha

Telescope: Altair Astro RC 250TT

Mount: Ioptron CEM60

Other equipment (e.g. camera, binoculars, etc.): Sky

watcher Esprit 100ED telescope and QSI 690CCD

imaging camera

I have been into astronomy for just over three years now. I spent years looking various telescopes and eyepieces

and enjoyed learning the night skies.

I loved what I saw and wanted to share with others who were less fortunate to own a telescope and decided the

best way to do that would be via images that I would capture.

After months of research and trial and errors I finally invested in a setup that I think would work for me.

My biggest challenges were to fend of the myths around imaging in city light polluted areas.

I spent living my life in London and never thought I could get a better sky than this. I was totally wrong! Several

hours out of London I was lucky enough to come across the most clearest and darkest skies. The challenge for

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me was to produce decent enough images to share,

however knowing the light pollution would restrict me.

I brought myself a CLS LP filter and attached it to the

front of my imaging train, that helped reduced light

pollution in the images that I took in colour, most com-

monly captured in RGB form.

I invested in a set of Narrow band filters and since

then I have never looked back. Theses filters would cut

straight though the light pollution and give me some

decent images. Although capturing an image is some

what difficult, processing them is most time consum-

ing as there are other techniques to really bring out

the images.

For me Astrophotography has been very rewarding.

You don’t need any expensive setup to produce NASA

quality images nor live in the darkies parts of the world

( Although it would help) My advice is to take small

steps, learn from your mistakes and keep working

towards your goal in Astrophotography.

Cigar galaxy

M82 lies at an estimated distance of 12 million light years

Imaged from London on Xmas day, the condi-tions were extremely poor

Altair Astro RC 250TT

ioptron CEM60 mount

QSI 690 CCD

L: 3 x 5 min

RGB 3 x 10 min

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Three top tips I can recommend

1. Plan your imaging object in advance, use

software like Stellarium to plan where your

target is going to be in the sky and how

much time you get capturing it.

2. Best time too image deep space objects

like galaxies and nebulae is when the moon

is not out in the night sky, this will ensure

you have a nice dark sky.

3. Image when your desired object is just

past the meridian line in the sky, that will

ensure you have the best sky conditions and

will help shy away from light pollution.

Jaspal

www.jkobservatory.net

www.jkobservatory.net

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www.jkobservatory.net

Cosmic clouds form fantastic shapes in the central regions of

emission nebula IC 1805. The clouds are sculpted by stellar

winds and radiation from massive hot stars in the nebula’s

newborn star cluster, Melotte 15

Melotte 15 - The core of the Heart Nebula - London

RC 250TT

Ioptron CEM60

QSI 690 CCD

Ha 15 x 20min

SII 8 x 20min

OIII 8 x 20min

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