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Originally Posted by SkyViking
Lol, Brent  Yeah I've got it here of course but just didn't want to post the image until I'd finished counting how many of it's globulars I picked up... 
Hmmm, I wonder what magnitude it has, from memory I believe HST regularly reaches to mag 29-30, and some of the large observatories go beyond that. It must be extremely faint. |
Interesting. So when we say a galaxy is say 100 million light years away it is incorrect to say the light we recorded is 100 million years old. Because the galaxy has most likely moved further away during part of that time so it may have been closer when it was emitted and the galaxy is now further away. But then we use received light to work out how far away something is so that distance as in the above example of 100 million light years would be the elapsed time and the galaxy may in fact in present time be much further away.
Greg.