The Andromeda Galaxy is tens of thousands of light years in diameter. That suggests that the most distant stars in the Andromeda galaxy is up to tens of thousands of years "behind" in their orbit around the galaxy, compared to the closest stars. Have anybody generated pictures of the galaxy, which shows the approximate real position of stars? Is this effect visible when looking at the Andromeda galaxy through an amateur telescope?
M31 is actually something like 141,000 light-years in diameter (there has been some variation in our understanding of its size, but 141K is good compromise). M31 is 2.54 million light-years from us. The rotational speed of stars near the edge of the galaxy's disk is in the vicinity of 200 km/sec.
Given all that, in one year a star in the vicinity of the outer edge of the galaxy's disk is going to traverse 6.3 x 109 km. At 2.54 x 106 light-years away, the apparent movement of such a star in the course of a year is going to be about 1.5 x 10-8 degrees, or 0.000054 arcseconds.
The Keck Telescopes in Hawaii, one of the most powerful telescopes in the world, has an angular resolution of 0.04 arcseconds.
As you can see, the best telescope in the world cannot distinguish any change of position of any star at that distance over the course of a year. It would take about 740 years before such a star would move far enough for a telescope with the angular resolution of the Keck to distinguish any movement at all.
So, it isn't visible through an amateur telescope either.
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