I'm Your Moon is a song written and performed by Jonathan Coulton from his album Thing a Week Four. It was the forty-seventh Thing a Week, released August 25, 2006. The song is a love song from Charon, Pluto's moon, who is attempting to cheer Pluto up after it had been "downgraded" to the rank of dwarf planet, which had not previously existed.
Pluto and Charon are rather alike in size, as far as (ex-)planets and moons go. They actually orbit about a point between them, instead of one revolving around the other. Additionally, they are tidally locked, that is, one side of Charon always faces one side of Pluto, and vice-versa. This gives the impression that they spin together in space, like dancers. The chorus illustrates this fact. (Educational!)
I'm your moon,
You're my moon,
We go round and round.
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