운석이 남긴 자국(아리조나/캘리포니아)
Barringer Meteor Crater This crater was formed about 50,000 years ago when an iron-rich meteoroid about 50 m (160 ft) across struck the ground near present-day Winslow, Arizona. It impacted at a speed of about 25,000 mph (40,000 km/h). The resulting blast was equivalent to the detonation of a 20-megaton hydrogen bomb, and left a crater 1.2 km (3/4 mile) wide and 200 m (650 ft) ..