Eli5: How do objects entering the earth atmosphere catch fire? is it from travelling to quick?
In: 1
It is because they’re going too fast, but that doesn’t explain why going fast makes things hot. Sometimes people say friction, but that’s not right.
Air has very little density, so little that you mostly can’t feel it while moving through it, but it’s still molecules with mass. If you’re going at the speeds objects reach while dropping from orbit, that mass matters. The heat is mostly from slamming into air faster than air can easily get out of the way, called “adiabatic compression.”
Latest Answers