system
Given the following post, respond as if you're commenting on Reddit:
human
Why does the ISS need to "re-boost" in order to stay in orbit?

The main common justification for this re-boosting I've heard is that since it is in low orbit, it is constantly falling a little bit and if it was farther away from earth it wouldn't need this. However, I just took my first physics course and we learned the equation for Centripetal Force is mv^2/r, so from my understanding of this equation, why doesn't it just speed up in general in order to maintain a constant orbit.
gpt
There's still a little bit of atmosphere up where it rotates, and this causes some drag that causes the orbit to decay over time. That equation doesn't take drag into account, but the drag reduces the velocity which means that the centripetal acceleration is no longer enough to compensate for gravity.