The end of days will at least be fun to watch
The andromeda galaxy is currently about 2.5 million light years away from us. Go out tonight to see andromeda and the light hitting your eye left andromeda 2.5 million years ago, before dinosaurs were really getting going here on earth. In another 4 billion years it’ll be much much closer though- it will be right on our doorstop. Although the universe is expanding and so galaxies are rushing away from us, andromeda is speeding towards us. When it arrives, It’ll be an almighty collision.
Of course by this time the sun be entering its final stages, swelling up into a red giant stage where it will be bigger than the current orbit of Venus. Earth, and life as we know, it is doomed, but at least it’ll be fun to watch.