Time shift in large DSO's.

[thing]

I was having a wonder about this the other night, if M31 is approx 150KLY wide then when you image it the back bit is 150K years older than the front bit. I don't know the rotational speed of M31 but if it is approx the same as ours, about 260M years then there must be some image shift, ie the back bit isn't where it should be. Has anyone ever produced a 'time corrected' image?

[Sam]

very interesting point - it'd be quite tricky to sort out!

[EA2007]

have to wait a long long time.........