An ellipsis has three dots! Never just two! (And never five or eight or however many you think looks the prettiest or the most “avant-garde.” *rolls eyes*)
Don’t capitalize universe (either time).
Capitalize Galaxy after Andromeda. (You’re right: you shouldn’t capitalize galaxy when it appears by itself. However, in this context, it’s part of a proper name.)
You probably ought to spell out kilometer (both times).
As 2017 ended…
150 billion stars formed in the universe.
The Andromeda Galaxy moved 3.5 billion kilometers closer to us.
The universe expanded by more than 60 trillion kilometers.
You can also spell out one hundred fifty, three-point-five, and sixty rather than using the numerals.