Asteroids have moons?

Question

How is this possible? How big is the asteroid? How big are/is the moon(s)?
So, If one of these particular asteroids were to hit earth, the asteroid and its moons would hit?

Answer 1

It's possible in the sense that it is possible for any smaller body to orbit a larger one. The asteroid moon is much smaller than the parent asteroid. Check out images of Ida and Dactyl, which were the first asteroid/moon system to be imaged directly. Ida is the main body, a few tens of miles across, while Dactyl is a tiny lump of rock just under a mile across.

And yes, if the asteroid were to impact Earth its companion would almsost certainly come with it. however, the impact of the parent asteroid will be the dominant effect. The little moon will just add a little extra trouble.

Answer 2

Some of them have, yes, for instance Eros has. They are usually quite a bit smaller. However, asteroids often seem to be piles of rocks held together by gravity anyway, so when there's a moon it's just another bit of the asteroid which isn't as attached. If they hit the Earth, the moons would probably hit as well, but it's also possible the asteroid would be pulled apart by the Earth's gravity anyway on the way down, due partly to the fact that they're piles of rocks.

Answer 3

Some do.

Size doesn't really matter - a rock the size of a basketball *could* have a moon. It depends on the forces acting on the two bodies - does the big one have enough mass to capture the small one, does the small one have the speed needed to orbit the big one, etc.

Well, it's possible (depending on the trajectory) for the big asteroid to hit Earth, while the small one skipped on by - or vice verse.

Answer 4

properly, an asteroid might desire to hit the two the moon or the earth promptly. Many hundreds have already completed so. the two the earth and the moon are concern to vast asteroid impacts which might rapidly destroy them. yet while the moon have been hit and destroyed the earth could be in a number of of hassle whether not one of the fragments hit the earth. that's by using fact the moon stabalizes the earth's tilt, proscribing it to polar angles of 10 to twenty ranges. devoid of the moon the earth's axis could initiate tilting further and further till it became swinging as much as ninety ranges to and fro. this could make the equator rotate around what at the instant are the N. and S. poles. In such situations there could be no seasons as we now know them, and maximum varieties of existence on earth could bypass extinct quite rapidly, inclusive of our very own.