General Information Crater formation is a result of a high velocity impact. A high velocity impact is a collision of a large body with a planet on a huge speed (several km/sec). Another commonly used synonym is “asteroid impact”. The body can be both a part of an asteroid or a comet. It’s important to mention, though, that crater formation is only one of the possible results of a high velocity impact. That only can happen if the extraterrestrial body is large enough (larger than a few hundred meters) to reach the Earth almost without substantial deceleration in the atmosphere. Otherwise the body won’t the destroyed after the collision and can be found as a meteorite. I would also like to stress that such a well-known phenomenon as “shooting stars” is in fact the result of small bodies deceleration and burning in the atmosphere.
Meteorites and meteoroids mainly originate as a part of an asteroid from outer space, and to be specific, from the Main Asteroid Belt between Mars and Jupiter. Every day thousands of small bodies cross over their path with the Earth’s, but only few of them are large enough to be seen. The collision of a large body with the Earth is, thankfully, a rare event. But it can have an enormous effect on our life.