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by naikrovek 393 days ago
What’s a moon that orbits a moon? Doesn’t that make the orbited moon a planet? Pluto has moons. But it’s not a planet? ???

If a super massive planet and two stars orbit each other in the center of a star system, all the planets that orbit those stars are moons then technically, right?

This is all super fuzzy and completely arbitrary. These concepts are constructs. Humans could make them better. Instead, everyone decided to make it all worse.

2 comments

No. A star is not a planet. The bodies orbiting the stars are planets, or dwarf planets, asteroids or comets. Bodies orbiting them are moons. Bodies orbiting the moons don't have a name.
> Bodies orbiting the moons don't have a name.

Satellites? Natural or manmade, small or big, doesn't matter.

A natural moon of a moon is called a subsatellite: https://en.m.wikipedia.org/wiki/Subsatellite

At present, purely theoretical: we don’t know of any. They are probably quite rare, but we don’t really know - maybe, in centuries to come, we’ll know of dozens of examples; maybe, there are none to find in this entire galaxy

Don't forgot about moonlets!