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The Moon is not drifting away, it's been thrown away by tidal interactions. The Earth's spin is slowing down and the moon is accelerating. Energy is going in to

The Moon is not drifting away, it's been thrown away by tidal interactions. The Earth's spin is slowing down and the moon is accelerating. Energy is going in to the Moon's orbit and coming out of Earth's angular momentum. My intuition is that without other sources of energy in the rings would decay eventually due to bits of them hitting each other occasionally, thus diverting some of them enough to interact with Saturn's atmosphere. Maybe there's some very small friction with gas from Saturn as well. The main point is that when anything diverts things down, the results are asymmetric with up, making down the overall trend. But as the article says, there is considerable energy input, with sunlight adding electromagnetic excitement so that things are getting diverted by the planet's magnetic field.

maxbond 3y ago
For sure. Seems hard to say, I'll bow to anyone's superior knowledge since I'm speculating right now, but I reckon a ring system may sometimes be a sort of natural optimizer which finds a stable configuration where they're far enough away to avoid the atmosphere and sparse enough that the effects between particles are negligible. The mechanism I propose here is that the most unstable parts of the system might deorbit first, leaving behind something stable. Again, wanton speculation from someone on the internet who's qualifications are that they thinks this is an interesting question to consider, don't take it anymore seriously than that.