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xkcd #2908: Moon Armor Index
(imgs.xkcd.com)
Alt text:
Astronomers are a little unsure of the applicability of this index, but NASA's Planetary Protection Officer is all in favor.
It's the largest relative moon (fifth largest in absolute terms) of any planet (sorry Pluto) and is more than a quarter as large as the earth itself. It's also relatively further from the planet than most moons in the solar system.
Fun fact, you can actually fit every single other planet at the same time in the space between the earth and the moon, with a bit to spare.
Though, not for very long. Gravity hates when you try things like this.
Yeah, if you see a real scale moon + earth distance, you wonder why he doesn't just fly away.