system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 How do Saturn’s rings exist? Shouldn’t the debris trapped in its gravity just float all over?
gpt
The rings exist the same way earth or the moon exists. The rocks are pulled in by gravity, but their lateral momentum is so fast that they never actually fall into the planet. They just keep revolving.

Early in the life of Saturn there would have been lots more rocks, floating in all different directions. But the ones that were too far out were lost, and the ones that were too far in crashed into Saturn. The only ones that survived are the ones that match this phenomenon.