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As several people have pointed out, a very strong ring around a spherically symmetric
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object is in an unstable gravitational equilibrium, which means that if it stays perfectly put,
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it’s fine, but if it gets nudged even just slightly off its perfectly centered position,
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it will then get pulled farther and farther from that position, since the part now closer
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to the earth gets pulled more strongly toward the earth than the part now farther from earth.
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So, it’s just like a perfectly balanced pencil.
