The nearest galaxy to us is already on its way here.
Andromeda sits 2.5 million light-years away — so remote that the light reaching your eyes tonight left before our species existed. And yet it's closing in on us at around 110 kilometres per second. In roughly 4.5 billion years, the two galaxies will begin to merge into one vast structure astronomers have nicknamed Milkomeda. Here's the part that catches most people off guard: almost no stars will actually collide. Galaxies look dense, but individual stars are separated by such vast distances that the two systems will largely pass through each other like two swarms of fireflies drifting together in an empty field. The night sky will be transformed beyond recognition — but Earth itself will most likely survive the encounter untouched. Follow Deep Field Vault for more of the universe's stranger truths.