On 15 Jan 2011, at 13:48, Stephen Peterson wrote:
One question that has always bothered me: How do we know that the star in question is indeed in or very near Andromeda? That is, for example, could it be half way there?
No one else has answered that one so I'll take a stab at it. I'll guessing that if it were a foreground star it's motion across the sky (proper motion) would be much different than stars in the distant galaxy.
When I look at really beautiful photos of Andromeda ( i.e. in SBIG's advertisement by Tony Hallas) it is easy to see clouds of stars but they, for the most part, appear unresolved as individuals. Have I missed some other confirming data?
The Hallas images and ones like them are great but are taken with scopes too small to provide the resolution needed to show individual stars in other galaxies. Clear skies! (please) patrick