Meteorites question, I have heard they were some knocked off the moon or mars,?

Question

How do they determine the meteorites origon and what knocked them off the planet or sattilite anyway?

Answer 1

We have samples of Moon rock from the Apollo missions (and a small additional amount from an unmanned Soviet sample return mission). For Mars, we have measurements of the surface taken by unmanned landers. We can compare these measurements with ones taken on meteorites to look for similarities.

What knocked them off the Moon and Mars was other, much larger meteoroids or even asteroids, that hit, made the giant craters we see there, and threw up lots of debris, some of which was thrown at more than escape velocity.

Answer 2

Some meteorites are created when other larger meteors hit a planet. It's a bit like dropping a brick into a puddle, splashes from the water fly from the pool in all directions.
We generally know where meteors come from by comparing the composition of the meteor. Samples of Lunar rock and samples of Martian rock have been analyzed and, by matching these we can guess where the meteor came from. Added to this trace elements from the atmosphere can sometimes be found in Martian meteors (the Moon has no atmosphere) Again using the puddle analogy, if there are two puddles, one muddy, one clear, and you drop a brick in one. If the splashes on a nearby wall are muddy, you know which bucket the brick landed in.

Answer 3

There are several methods used to determine origin, including radiation signatures, chemical composition, and molecular structure.