From perpendicular angel knowledgebase
- Asteroid Fast Facts
- How big does a meteor have to be to make it to the ground? Hint: Anywhere from dust on up
- Meteor Smoke Makes Strange Clouds
- How far can we see if unobstructed? Hint: usually 12 miles.
Caves and Caving
- Breccia: a rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix that can be similar to or different from the composition of the fragments. May be formed by an impact.