eli5: Why is the Kessler effect so dangerous? Won’t the space junk eventually fall out of orbit or drift off into space?

Question

I saw the opening of *Gravity* and it was pretty terrifying, but to quote Billy Bob Thornton in *Armageddon*, it’s a big-ass sky.

In: 14

Answer 1

*Gravity*’s physics is not the best out there, but the premise of a kessler cascade is sound.

It’s a big sky, but it only takes a little bit of debris to destroy a satellite and one destroyed satellite produces a *lot* of debris.

And yeah, after a few years most of it will be gone, but not all of it.

Higher orbits will last much longer, so depending on how high our satellites are that have the issue, it could go on a *very* long time.