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So you want Galaxies : How many can you count ?

Catanonia

By Catanonia
in Imaging - Deep Sky

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Catanonia

Catanonia

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A fun night last night with lovely clear skies again over Sandbach Cheshire. I started out wanting to try and get M51 at 2700mm F21 and managed to get a few images. But way to noisey for the EOS 350D at the sub length required to get any data. I kinda knew this would happen, but really wanted to have a go at it.

So after a few discussions and a challenge from TJ I plumped for NGC 7331 galaxy area.

1st thoughts are .. WOW it is small, even with the ED120 F7.5 at 900mm, but I persisted with over 3 hours worth of imaging until about 3am.

So count the galaxies in this crop.

NGC%207331%20-%20St%20Stephans%20Small.jpg

To the left is the galaxy cluster of NGC 7331, a galaxy likened to our own Milky Way. You can also see St Stephans Quintet Galaxy cluster to the right. Apparently it is 25 times the distance that M31 Andromeda is from us.

Discovered by William Herschel in 1784.

NGC 7331 is one of the brighter galaxies which is not included in Messier's catalog. It exposes a fine spiral structure despite its small inclination from the edge-on position. Several companions and background galaxies are visible.

NGC 7331 was among the earliest recognized spiral galaxies, and listed by Lord Rosse in his list of 14 "spiral or curvilinear nebulae" discovered before 1850. One supernova has been discovered in NGC 7331 so far: SN 1959D, discovered by Milton Humason at 32"W and 13"N of the galaxy's nucleus. This supernova became as bright as 13.4 mag (see IAUC 1682 and PASP 105, 1250).

Another crop this time

NGC%207331%20Large.jpg

A closer look at the St Stephans Quintet

Stephan's Quintet, as its name implies, is a group of five galaxies (NGC7317, 7318A, 7318B, 7319 and 7320) in the constellation Pegasus. This unusual system has often been used as proof that the redshift is not truly a distance indicator, which would completely overturn current cosmology, because although four of the galaxies have similar, large redshifts, the fifth (NGC7320), although apparently a member of the group, shows a much smaller redshift. Conventional theory states that the low-redshift galaxy is in a nearby group (the NGC7331 group) and by coincidence appears on the sky projected against a distant background group. Opponents point to debris and tails around the low-redshift galaxy, suggesting that it is interacting with the high-redshift systems, which would require that all five galaxies be at the same physical location in space.

St%20Stephans.jpg

The full size image can be found at this link

http://extraview.dnsalias.com/temp/NGC%207331%20-%20St%20Stephans%20Large.jpg

Imaged as follows.

SkyWatcher ED120 Evostar Pro 900mm F7.5 with EOS 350D Baader modded with Astronomik CSL LP clip filter

Guided with Skywatcher ED80 with QHY5 on EQ6 Pro mount on 17th August 2009

2.5 hours of 5 min subs with darks, flats and dark flats applied.

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Catanonia

Catanonia

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Marvellous. I've lost count btw I quite like the background left slightly blue. Jerry Lodriguss does that as well

I feel it is more natural instead of over processing. Someone on another forum reminded me constantly not to chop off the left of the histogram.

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albedo0.39

albedo0.39

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Imaging ... I dunno what the fuss is all about...:);)

Actually, it's simply remarkable to me - despite being a technocrat of sorts -that this quality is achievable without professional kit. I'm always impressed by any of the imaging work I see in SGL - mainly because I understand how much effort usually goes into the piccie.

Thanks for posting. Cannot wait to see Stephans Quintet in the flesh

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