It's made of moon stuff.
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Tachytaenius
the same stuff as the sun, that's why it glows /j
Yoop90-
horse manure
Travlordian01⚡️
Moon rocks
Ordinary Orange
ham?
Mug Not Found
A material which is unusually good at conducting portals.
Jackiethederg
The moon isn't real, silly!
Dark Sunshine
Partly Earth and partly another planet whose name I forgot
Tachytaenius
That's Theia.
Erinit🌳
rock
Evil Ghost Lady
Endstone.
Elemental Δ
It's no moon, it's a giant metal orb!
Kane Schmitz
Moon is made of moon
Willow the wisp
It's composed largely of aluminium and iron
Golden Heretic Snakeboat
the moon is clearly bread
Chococlover641
As you may know the moon is an interstellar object that was formed when earth collided with a planet the size of Mars. Debris from the impact collected in an orbit around Earth to form the moon. So my conclusion is that the moon is made out of 
Space Rock.
Space Rock.
Actual answer: it's a giant grey watermelon, not a moon.