Someone told me the moon was once a piece of the Earth, and was knocked off by a colision with a meter........

Question

...is this true?

Answer 1

Well, the second body would have been an asteroid. It is indeed true that the collision theory is favored at this point over the capture theory, the coalescence theory, and the theory that the moon was thrown off the earth when it was (presumably, according to the theory) molten. In the collision theory a large asteroid struck the earth and caused enough material to escape the earth and form the moon (then by coalescing of the many smaller particles). It would have happened very early on in the solar system. Supporting information of this theory includes the identical isotopic makeup of many of the elements found on the moon through the Apollo landings in the late '60's and early '70's.

Answer 2

That theory matches all the observed evidence, and scientists have created computer models that show that it would work. I've heard it called the collision-ejection theory, Wikipedia calls it the Giant Impact Hypothesis. Doesn't really matter.

We're not talking just a meteoroid or asteroid hitting the early Earth, we talking something that had half the diameter of Earth! Roughly the size of Mars! It hit Earth broadside (not head-on) and was destroyed by the impact. Bits of that object and bits of Earth were flung into orbit around Earth (Earth would've had a ring for a while). Some bits came back down to Earth. Others stayed in orbit and eventually coalesced to form the Moon.

Answer 3

The current theory goes something like this:

Billions of years ago when the earth was still molten, it was struck by a planet. The explosion ripped away part of the Earth. Gravity took over and formed the debris into the moon.

Analysis of the moon rocks recovered form the Apollo Astronauts revealed the moon is made up mostly of silicates. Since the Earth was still molten, the heaver elements didn't yet form.

Answer 4

i read the earth was hit by a comet or a large asteroid when earth was still in a semi molten condition and it probably just hit 1 corner of earth not rite in the middle which cause a blob of earth to move away and got into orbit like a regular sattelite.

Answer 5

That is the current theory, yes.

Answer 6

thats just because people cant exlain if the sun has more gravity than earth why doesnt the earth hit the sun


their maybe air in space and wind is making the earth travel around the sun like its supposed to ya i know astronauts think their is no air but if you dont know what you are doing then youll push all the air off of you


the air can tell you any thing going on any where in the world or maybe space

Answer 7

that's 1 theory. Is it true? That's still being lookied into.