We may receive a commission on purchases made from links. Are we alone in the universe? It's a huge question with no easy answer. And, following on from that, if we aren't alone, what would beings from other planets think of us — and how would they ...

Do aliens exist? Based on how many alien invasion movies there are, you'd be forgiven that there's gotta be some proof of extraterrestrial life—and that the aliens are out to get us here on Earth. But, for now, attacking aliens are just the stuff of fiction.