When a really big rock (or a huge chunk of iron) hits Earth, why does it explode instead of just making a lot of rubble?
Bill Albertson, Ann Arbor, Michigan
Published: Monday, June 25, 2012
Meteorite impacts are profoundly different from the more familiar impacts of bullets because of the enormous energy objects moving at meteoritic velocities carry. At such speeds, the final crater is essentially blasted out as if by an explosion, rather than by simply pushing material aside.
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