There are no moons in the solar sytem which have been onserved to have natural satellites, right? What’s up with that? It can’t be a size issue, becaue lowly Pluto has a moon (sort of), and there’s even an asteroid (Gaspra? Ida? remind me…) with a satellite.
Is there something about orbital mechanics that makes it impossible to orbit something that orbits something that orbits something? That doesn’t seem to track either, what with the Apollo missions and all.
Oh, wait, I forgot, those were faked. Never mind.
Anyway, is there a chance that there are moons within moons that we just plain can’t see?
Yeah, something as small (compared to the Moon) as the Apollo mission capsule would be able to orbit the Moon with little interference from the gravity of the Earth or the Sun.
The main problem with metamoons is that once they get large enough to be important, they start messing up the gravity of the system, and chaos theory takes hold (isn’t that how early chaos theory was developed? motion of a 3-body system or somehting…). It works with the Earth, Moon and Sun because we’re so far away from the Sun that the centre of gravity of the Earth-Moon system doesn’t move much. Since the Moon is much closer to us than we are to the Sun, you’ll need something small to orbit the Moon so it doesn’t affect its centre of gravity, but allows it to keep orbiting the Earth like it should. Which is where your small, light Apollo ship comes in.
As always, I’m not too sure about this (especially the centre of gravity stuff), but you’re right, a small enough metamoon could accomplish this. The trouble will be getting it there.
Don’t think there’s any real reason this couldn’t happen, though I imagine the moons would have to be pretty small.
Note there are many who think that Pluto was once a moon of one of the bigger planets itself, and it has it’s moon Charon, so that’s a possible example.
I believe Chaos Theory started when a meteorologist made some rounding errors in a weather simulating program, leading to vastly different results from the original run, sometime in a 1970s.
Anymore, the theory isn’t so much that Pluto was once a moon, but that some moons were once things like Pluto and Charon, i. e., Kuiper belt objects.
I’ve actually got a Staff Report on this on the back burner somewhere… I suspect that there would be stability issues, but I haven’t done the calculations yet. Chaos theory can come in in the general N-body problem, but there’s plenty of non-chaotic special cases, so that’s not an absolute answer.
My understanding is that for the case of the Earth’s Moon, any orbit around it is unstable in the long term. Long term may mean hundreds of millions of years, but the solar system has existed for longer than that. This applies to objects of all sizes, even those smaller than the Lunar Orbiter.
What causes lunar orbits to be unstable is that they are perturbed by both the sun and the Earth. Eventually, any object in lunar orbit will either crash into the Moon or leave the Earth-Moon system.
Well “micro” meta moons (now thats a mouthful) might exist in the form of atmospheres/“dust”…everything that orbits a body is made of something. Though it might be small, it is still orbiting due to gravitational pull.