ManusJustus said:
Most scientists think that the moon is the result of a collision between Earth and rogue planet the size of Mars billions of years ago. The collision would have threw large amounts of Earth's crust into orbit, and that mass eventually formed into our moon. Since the moon and Earth's crust have similar composition, this idea is well founded. This seems catrostrophic, but this was actually a blessing for Earth. The moon keeps Earth's axis from tilting wildly and the collision with another 'planet' gave Earth a larger iron core resulting in a much stronger magnetic field than we should have. Both of these make life on Earth much easier. Also, the moon is moving farther and farther away from Earth. This is a result of lost gravitational energy from Earth's bulge it forms with the moon (tides, but the crust moves slightly as well). This is no concern, however, because the sun will die long before we lose the moon. |
that could not have happened billions of years ago, because if it did that means the moon was a hell of a lot closer than it is today. how close do you guess the moon was to earth when it was first formed?
