How does a galaxy differ from a star?

1 Answer
Jan 31, 2016

A galaxy is a collection of stars, held together as a group by gravity...


A galaxy is a collection of anywhere between a few thousands and one hundred trillion (#10^14#) stars, held together by gravity.

Apart from our own Milky Way galaxy, to which the individual stars you can see belong, with the naked eye you can see the centre of the Andromeda Galaxy (M31) as a fuzzy little patch of light.

M31 is about #2# million light years away. So we see it as it was about #2# million years ago.