7/14/2002: Asteroid moon

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Now there's something you don't see every day. An asteroid with a MOON.

This was on Astronomy pic of the day and comes from Galileo. It found these two on its way to Jupiter. The asteroid's name is Ida, the moon's name is Dactyl. The moon is only one mile across, while the asteroid is 36 miles long.

The best image of the moon:



"That's no moon"

Imagine if you were standing on it. You could easily see the rounded horizon. What I wonder is, if you jumped, would you jump OFF? The gravity on that thing must be tiny. And yet, the craters on it say that it's been hit by debris and it wasn't knocked out of orbit of its big brother, or so we have to assume.