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SkyViking
16-10-2012, 09:52 PM
Hi All,
During the last few weeks I miraculously succeeded in scraping enough data together to make this deep view of one of my favourite galaxies: The Cartwheel Galaxy, famous from the Hubble image taken back in 1995. Surprisingly there are only a couple of amateur images of this galaxy. It is rather small though, at 1.39 x 1.17 arcminutes in diameter. I was pleasantly surprised to find that the background is bursting with distant galaxy clusters, actually most of the faint specks in this image are galaxies, not stars...

I have also added my previous effort with the ToUCam to this post. The new version is a slight improvement :lol:

Link to large size image (http://www.rolfolsenastrophotography.com/Astrophotography/Galaxies/25329559_xL3ckk#!i=2153490384&k=WZdM6jW&lb=1&s=X3)

Link to original size image (http://www.rolfolsenastrophotography.com/Astrophotography/Galaxies/25329559_xL3ckk#!i=2153490384&k=WZdM6jW&lb=1&s=O) (2.5MB) (Check this one to see all the details in the galaxy itself)


Details:
Date: 22nd September and 9th/10th/11th October 2012
Exposure: LRGB: 630:70:65:65m, total 13hrs 50mins @ -30C
Telescope: 10" Serrurier Truss Newtonian f/5
Camera: QSI 683wsg with Lodestar guider
Filters: Astrodon LRGB E-Series Gen 2

About the image:
The Cartwheel Galaxy is a distant galaxy located 400 million light years away in the southern constellation Sculptor. It features a unique ring structure, most likely as a result of a head-on collision 200 million years ago with a smaller intruder galaxy that passed though the very core of the larger galaxy. The density wave set in motion by the passage of the intruder is visible as intense starburst activity along the edge of a massive ring that is slowly making its way outwards from the centre, like a ripple on a pond.
The galaxy is part of a small group of four, with the other members being the smaller blue and yellow galaxies right next to the Cartwheel and another companion a little further north (down). The latter is believed to be the intruder galaxy. In fact, high resolution radio observations have identified a trail of neutral hydrogen gas between the Cartwheel and the intruder, strongly suggesting that this is indeed the culprit now fleeing the scene.
Images from the Hubble Space Telescope (http://www.spacetelescope.org/static/archives/images/screen/potw1036a.jpg) show the bright knots in the ring to be giant clusters of super luminous young blue stars. These bright stars will live and die in a few million years, well before the density wave has moved on, and new stars will continue to be born of the same recycled matter in this chaotic setting of intense starburst activity and cataclysmic supernovae brought about by a cosmic encounter 200 million years ago.
Eventually the wave will dissipate and fade out into the outer regions of the galaxy where the gas and dust is too thin for new stars to be born. Looking like the spokes of a giant wheel, faint spiral arms can already be seen beginning to form again after the collision. The galaxy will probably take on the form of a normal spiral again in the future.
Looming in the background of the image are large numbers and groupings of faint distant galaxies, visibly clumping together and forming the large scale superstructure of the Universe. Many of these lie in the neighbourhood of the Sculptor Wall, a gigantic structure of galaxy clusters that stretches outwards for more than a billion light years.

Hope you enjoy, comments and critique welcome as always.

Regards,
Rolf

Larryp
16-10-2012, 10:01 PM
Nice image!

Mark_Heli
16-10-2012, 10:04 PM
Hi Rolf,

That's an awesome image. A very unusual shaped galaxy.

Cheers,
Mark

RickS
16-10-2012, 10:09 PM
Very cool, Rolf!

strongmanmike
17-10-2012, 07:50 AM
This is an amazing image Rolf...0.6' huh? That is tiny, it looks bigger than that or else your seeing is excellent. Crazy looking galaxy that, almost looks more like a PN than a galaxy.

Great work mate, I like your choice of targets, you have a nice collection of interesting things in your portfolio.

Mike

SkyViking
17-10-2012, 08:23 AM
Thanks for the comments guys :)



Thanks Mike, you're right I got 0.6' from SIMBAD but that appears too small. I've just counted the pixels now and I get 1.39' x 1.17' as the exact size. Still small but not that small.
Hm, maybe 0.6' is meant to be the radius?

strongmanmike
17-10-2012, 08:24 AM
Probably the central bit is 0.6'...?

Either way it's a beaut image mate :thumbsup:

Mike

TheDecepticon
17-10-2012, 11:18 AM
Another nice shot! Top object to choose. :)

allan gould
17-10-2012, 12:46 PM
Exceptionally clean, detailed and interesting image. Really well done.

multiweb
17-10-2012, 02:35 PM
Wow!... Uber cool Rolf. Top notch. :thumbsup:

Stevec35
17-10-2012, 06:14 PM
Another top shelf image Rolf! Very nice description too.

Cheers

Steve

Peter Ward
17-10-2012, 07:50 PM
I've tried this one... doomed to failure from the burb's of Sydney as it's stupidly faint.

You effort is however a sublime achievement! As far as I can tell, few
have done so well.

Simply excellent :thumbsup::thumbsup::thumbsup:

pixelsaurus
17-10-2012, 07:59 PM
Nice one mate!

DavidU
17-10-2012, 10:04 PM
Awesome:thumbsup:

Paul Haese
17-10-2012, 11:07 PM
Great image given the faintness of this galaxy. I like the knots and spokes. Excellent detail.

Leonardo70
17-10-2012, 11:46 PM
Great job :thumbsup: .... incredible galaxy ... congrats.

All the best,
Leo

iceman
18-10-2012, 04:41 AM
Stunning work, thanks for sharing!

marco
18-10-2012, 09:06 PM
Fantastic Rolf, I really appreciate your efforts to produce images of very difficult objects, I have to say that I would not have tried such a small target in your feet, you proven me I would have been wrong :)
:thumbsup::thumbsup::thumbsup:

Clear skies
Marco

Ross G
19-10-2012, 09:36 PM
Amazing capture Rolf.

Looks great.

Ross.

SkyViking
22-10-2012, 09:11 PM
Thanks very much Mike :) Yeah don't really know what 0.6' is referring to, the yellowish central ring seems much smaller :shrug: But I have updated the image text with the correct dimension now.


Thank you Graham, I've always liked this galaxy.


Thanks Allan, I'm glad you liked it.


Thank you Marc, I've been wanting to do this one for the last 7 years, since I took the webcam image of it, but I really needed much more sensitivity to do it any justice.


Thank you Steve, I like to dig up some interesting info about the objects I choose, I'm glad you enjoyed the read too.


Thank you for your kind words Peter. I'm also happy with how it turned out and is a very interesting field too. Not many amateur images to compare with though. I found one from AAO that is quite similar: http://apod.nasa.gov/apod/image/0106/cartwheel_aao_big.jpg


Thanks Mike :)


Thank you David :)


Thanks Paul :) The structure of the galaxy is fascinating, one can really sense how it is starting to form a spiral again, it looks very dynamic.


Thank you Leo, glad you liked it :)


Thanks Mike :)


Thanks very much Marco, it is small indeed but the striking ring structure makes it a delightful target. I'm glad I was able to tick this one off the bucket list (although I'm sure I'll revisit it in the future) ;)


Thank you Ross :)

marc4darkskies
22-10-2012, 10:12 PM
This is a lovely image of a difficult subject Rolf! Although it would be nice to have the magnification to bring the Cartwheel a bit closer, you've captured some nice detail and the pretty field it's embedded in more than makes up for it. Very nicely done!

Cheers, Marcus