The Great Inter-Galactic Crash

The illustration above is of what the night sky will most likely look like far into the future -- as the Andromeda galaxy crashes into our own Milky Way galaxy. Scientists have long known that the two galaxies have a gravitational pull on each other, even though they are millions of light years apart. But they could not predict if or when the two galaxies might collide, because they could not measure the sideways motion of Andromeda.

But by using the Hubble Telescope, they have now been able to make those measurements. And they found the two galaxies will indeed crash together, and form one elongated giant galaxy (much like many other elongated galaxies seen throughout the universe).

There's no need to worry though. The two galaxies won't collide for another 4 billion years (and then take another two billion years to form the final elongated galaxy). That's plenty of time for the human race to finish destroying itself -- as it seems intent upon doing. It'll sure be a fine show for whatever species rules this Earth after we are gone though.