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11 votes
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What exactly is a "moon"?

Unlike "planet" the IAU hasn't attempted to precisely define "moon". General usage requires that a "moon" is a natural satellite of a planet (or dwarf planet, asteroid, or perhaps even of another moon?...
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3 votes
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Can moons exist inside a planet's roche limit?

You've answered you own question. If there are cohesive forces beyond that of simple self-gravitation, then objects can survive intact inside the self-gravitating Roche limit - as does every solid ...
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3 votes
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Are Saturn's rings stable?

Most of Saturn's rings are inside it's Roche limit, which means they will never clump together. Tidal forces prevent this from happening. small objects that are already together can withstand the ...
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3 votes
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What is the difference between a moon and a random chunk in the rings

Your question: There also are satellites in between the rings. What distinguishes a moon from any other chunk in orbit around a planet? Wikipedia should be taken with a grain of salt, but they ...
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2 votes

What is the difference between a moon and a random chunk in the rings

A diameter of 0.5 kilometer will get you classified as a moonlet. See Aegaeon. Apparently at 1.4 km × 0.5 km × 0.4 km, it is on the edge of the definition.
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2 votes

What exactly is a "moon"?

According to NASA - What is a Moon?: Planets and asteroids orbit the Sun. Moons—also known as natural satellites—orbit planets and asteroids. Moons come in many shapes, sizes and types. Most are ...
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1 vote

Can moons exist inside a planet's roche limit?

tl;dr: Yes, but they must be small. The reason why is because large bodies, like major moons, break apart at a certain limit from their hosts, using the formula for the Roche Limit: $$d=r\Big{(}2\...
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1 vote

Should only spherical satellites be considered 'moons'?

The need to distinguish between these potato-shaped and spherical moons hasn't arisen. As such, there aren't two different words to designate these two types of moons. And as long as the community of ...
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