A rigid ring or sphere surrounding a single massive body will not be stable, but in the “restricted 3-body problem” where the ring/sphere is infinitesimally light, and one massive body is orbiting another, there can be some stable configurations.
For example, if the lighter of the two bodies is less than 1/9 the mass of the heavier one, a rigid sphere enclosing the lighter body can be stable.
H/T Shubhendu Trivedi
https://academic.oup.com/mnras/article/537/2/1249/7989465
Greg Egan /
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2025-02-20 08:52:32
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2025-02-20 08:52:32Event JSON
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"content": "A rigid ring or sphere surrounding a single massive body will not be stable, but in the “restricted 3-body problem” where the ring/sphere is infinitesimally light, and one massive body is orbiting another, there can be some stable configurations.\n\nFor example, if the lighter of the two bodies is less than 1/9 the mass of the heavier one, a rigid sphere enclosing the lighter body can be stable.\n\nH/T Shubhendu Trivedi\n\nhttps://academic.oup.com/mnras/article/537/2/1249/7989465",
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