If were in space then what is space in what is space expanding into?

Answer:
No one knows for sure. There are theories, but absolutely none of them can be proved, and I doubt we will ever find out. The universe is expanding firther into what was here before the big bang. Basically, nothing. The universe isn't expanding like a balloon blowing up; the universe is already there, but the objects inside it are spreading out constantly (black holes, stars, galaxies, etc.) The universe isn't expanding; the objects inside are spreading out within it.
First answer by ID1443160199. Last edit by Lilybobluv. Contributor trust: 0 [recommend contributor recommended]. Question popularity: 1 [recommend question].