The most amazing characteristic of this region is how many galaxies there are - maybe 3000 are visible as faint smudges (down to about Bmag25). Most are found in a sweeping arc from the top left to bottom right in the image, but they are also spread across the rest of the field at lower densities. An intriguing and highly red-shifted group is seen at the left of http://www.astrobin.com/full/221267/0/ which is from the top left of the main image - these are a lonng way away.
There is a high mass concentration down and to the left of centre in the main image - this is the Abell2667 region imaged in one of the Hubble Frontier Fields. The image is lightened a bit and shown alongside Hubble data for easy interpretation: http://www.astrobin.com/full/221266/0/. The main galaxies are redshifted by z=0.23, so the light has taken about 2.8 billion years to get here - and the UV light (now blue) is reduced by some stellar absorption bands, so most galaxies look yellow/orange. The big blue galaxy is radiating significant UV (now blue). It is being torn apart by gravity and pressure effects as it falls through the intra-cluster medium. Some of the galaxy scraps can be seen as a wake. The other main interest in the region is the huge gravitational arc, which is a magnified triple image of a far off galaxy situated well behind the main cluster. The gravity in the cluster is sufficient to form a lens (the equivalent of a refractor much bigger than the milky way) and this magnifies and condenses the background light. The arc has a red shift of z=1.03, which means that these ancient photons have been travelling for about 8 billion years. When they started out, the solar system did not exist and the universe has changed so much since that the UVA, UVB and UVC light from the arc galaxy is now (roughly) RGB - the colour actually looks like it does not quite belong in this universe come to think of it...
had great fun imaging and trying to understand more about this region - thanks for looking. regards ray
P.S. don't bother with the JPEG below - it doesn't show the whole region.
A magnificent image, Ray. The gravitationally lensed arc is spine-tingling. It's going to take me quite a while to fully absorb this one, but wanted to say something straight away. Thanks for the careful explanation.
Hi Ray,
you're doing very well with that 10" f4 Newt.
This latest picture is very interesting - so many galaxies!
It gives me some encouragement with my Newt.
A very interesting project Ray with a very worthwhile outcome, great work!
Comparing with Hubble data really allows us to interpret what we have captured and shows that there is probably plenty of stuff in many of our images that we just write off as stars but may indeed be much more
that is simply stunning Ray, it is images like this which are the reason why i love astronomy so much. it starts to give you some perspective of the scale of the universe.
Just Amazing .... makes our solar neighbor hood looks so insignificant.
A lot of stuff out there.....
Thanks for the pic and info
Col.....
thanks Col. we are a just a dot on the map really.
Quote:
Originally Posted by Placidus
A magnificent image, Ray. The gravitationally lensed arc is spine-tingling. It's going to take me quite a while to fully absorb this one, but wanted to say something straight away. Thanks for the careful explanation.
Very best,
Mike
thanks Mike. There are quite a few interesting papers on this area - found most using Google scholar.
Quote:
Originally Posted by RobF
Mind blowing really.
Thanks Ray. Awesome work. Mesmerizing field....
thanks Rob - appreciated
Quote:
Originally Posted by DJT
Love it. Swanning around the galaxy clusters on the iPad. nicely handled, interesting info. Thanks for sharing, Ray
Thank you David - it is interesting to ponder how much there is out there.
Quote:
Originally Posted by Rod771
Amazing,Ray! Totally mind blowing. Appreciate the info.
Thanks Rod - just hope I got most of the info right...
Quote:
Originally Posted by Peter Ward
While there are many pretty pictures out there only a handful have the ability to inspire....which you've done in spades here
thank you Peter. that's very generous.
Quote:
Originally Posted by alpal
Hi Ray,
you're doing very well with that 10" f4 Newt.
This latest picture is very interesting - so many galaxies!
It gives me some encouragement with my Newt.
cheers
Allan
Hi Allan. thanks - looking forward to your next image with the new scope.
Quote:
Originally Posted by DJScotty
Superb image ray. The detail is absolutely mind blowing.
thank you Scott - much appreciated
Quote:
Originally Posted by Paul Haese
There are so many orange smudges. Drake equation Ray?
thanks Paul. The Drake equation can give anything you like, but we have one example of a galaxy with at least one advanced? civilisation at the current time, so taking that single point as the best available data, then each of these 3000 galaxies may have had a roughly similar civilization when this light started out .... or not
Quote:
Originally Posted by strongmanmike
A very interesting project Ray with a very worthwhile outcome, great work!
Comparing with Hubble data really allows us to interpret what we have captured and shows that there is probably plenty of stuff in many of our images that we just write off as stars but may indeed be much more
Great bit of imaging
Mike
that's a good point Mike. In the plane of the Milky way, we obviously see stars, but in out of the way places, galaxies rule if you go reasonably deep - which is staggering.
Quote:
Originally Posted by Stevec35
A very impressive result Ray!
Steve
thanks a lot Steve
Quote:
Originally Posted by Somnium
that is simply stunning Ray, it is images like this which are the reason why i love astronomy so much. it starts to give you some perspective of the scale of the universe.
Thanks Aidan - yep, I can't get my head around these far off clusters, but it is fun to try to understand how vast the universe really is.
That's pretty special. I'd casually wondered if gravitational-lensed galaxy arcs were possible for amateur imaging, you've shown that beautifully! And the whole image is a treat to explore.
Two quick questions:
There's a broad faint bluish streak on the centre right of the image - any thoughts on what it is (IFN, something else?)
Ohh WOW!! That just brought a huge grin to my face and made me laugh... simply breathtaking... Thankyou.
thanks Joshua - glad you enjoyed it.
Quote:
Originally Posted by andyc
That's pretty special. I'd casually wondered if gravitational-lensed galaxy arcs were possible for amateur imaging, you've shown that beautifully! And the whole image is a treat to explore.
Two quick questions:
There's a broad faint bluish streak on the centre right of the image - any thoughts on what it is (IFN, something else?)
What exposures did you use for imaging?
Thanks Andy. the streak is aligned with the spider diffraction patterns, so it might be diffraction from a bright out-of-field star. It could also be light leakage (camera?) since my imaging environment is fairly bright due to local streetlights. Still to tie down exactly what it is.
Exposure? - will get back to you. there have been a lot of versions of this with different sub selection criteria and I did not keep a tally of how many subs were used in the final version. However, all subs were 5 minutes and the usable data was selected from ~30 hours in total. I think that it is reasonably deep, with galaxies (identified elsewhere) of ~m24 being easily identified and the 3sigma is probably somewhere around m25.
