Ever since the earth formed, it's been bombarded with stuff from outer space. Most of this stuff is small, and doesn't even make it to the ground. We see this as falling stars, and meteor showers. Occasionally this stuff is big enough to hit us, with sometimes devastating consequences. At least once it has caused a mass extinction.
Rocks from other planets lands on earth as well, giving us glimpses of their geology without us having to visit.
All this is Impact.
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Articles in category "Impact"
There are 17 articles in this category.