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Considering that there's a lot of debris in space and that impacts fling out rocks into space all the time, why do we only have one large natural satellite - the Moon? Shouldn't there be all kinds of rocks in all shapes and sizes orbiting the Earth?

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Earth has few and relatively tiny sattellites other than the moon specifically because of this large moon. Note the mass ratio of our moon to our planet. It is the highest in the solar system by a large amount. This one large sattellite will over time sweep up and aggregate other smaller sattellites.

Put another way, we probably did have other smaller satellites, but they've all crashed into the moon by now, or the moon messed up their orbits to the point where they crashed into earth.

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    $\begingroup$ Sidenote: Moon is above its Roche limit (on Moon-Earth distance), which means that the gravitational force of the Moon is high enough to keep it together and even attract nearby objects to it; Earth is so far that gradient of its field is not strong enough to pull the Moon apart. $\endgroup$ – Ján Lalinský Apr 11 '14 at 17:40
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When the the earth was formed. I guess only the moon was close enough in proxmity to be attracted by the gravity of the earth or rather earth cant hold anymore natural sattelites but the moon.

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  • $\begingroup$ Also, ome moons formed from clumps of matter that formed in discs of gas and dust that orbited the parent planet. Parent planet in this case would be our own mother earth. $\endgroup$ – Physician Apr 11 '14 at 10:24
  • $\begingroup$ If the moon was initially in orbit around the sun and not yet around Earth it can't just get into orbit around Earth trough a close encounter with it. There is a theory that the moon formed after a collision of a smaller planet (size of Mars) with Earth. Something similar must have happened such that a body would not escape Earth gravity well after an encouter. $\endgroup$ – fibonatic Apr 11 '14 at 10:55
  • $\begingroup$ Yeah this makes sense too. (Y) $\endgroup$ – Physician Apr 11 '14 at 11:03
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The moon is by far the largest of earths natural satellites, but is by no means the only one. There are many much smaller bodies which either orbit earth or have an orbit around the sun which is extremely similar to that of earth. The moon is the most significant and largest as it is the result of large amounts of matter clumped together that was thrown off earth in a planetary collision.

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  • $\begingroup$ The other planet struck earth at a 45 degree angle and was the size of mars. This created a disk of debris around earth which formed the moon $\endgroup$ – stanley dodds Apr 11 '14 at 11:50

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