Lifeboat Foundation

The “outside the universe” question gets tricky right off the bat, because first you have to define the universe. One common answer is called the observable universe, and it’s defined by the speed of light. Since we can only see things when the light they emit or reflect reaches us, we can never see farther than the farthest distance light can travel in the time the universe has existed. That means the observable universe keeps getting bigger, but it is finite – the amount is sometimes referred to as the Hubble Volume, after the telescope that has given us our most distant views of the universe. We’ll never be able to see beyond that boundary, so for all intents and purposes, it’s the only universe we’ll ever interact with.