A meteor impact about 50,000 years ago left this crater 4000 ft (1200m) in diameter and 570 ft (170m) deep. The speed at impact was about 28,600 mph (12.8 kilometers per second), resulting in a massive explosion equivalent to at least 2.5 megatons of TNT – equivalent to a large thermonuclear explosion and about 150 times the yield of the atomic bombs used at Hiroshima and Nagasaki.