Meteor Crater near
Winslow, Arizona, was the first impact crater to be recognized as such.
In 1957, a young graduate student named Eugene Shoemaker (later of Comet
Shoemaker-Levy fame) convinced scientists that the iron fragments, a
layer of broken rocks, and melted globs of soil were caused by a meteorite,
not a volcano. Photo courtesy of John S. Shelton.