^{Credit: ESA/Hubble & NASA/STScI} 

Beware, Andromeda is coming!

Well, very very slowly, at least. In approximately 4 billion years, our nearest galaxy Andromeda, will smash right into ours and they will both merge, forming a brand new galaxy.

If there's still life on Earth that far in the future, what would the sky look like? This fascinating video explains this awesome event in detail.