Explanation:
Barringer
Meteorite Crater, near Winslow, Arizona, is one
of the best known impact craters on
planet Earth.
View this color stereo anaglyph
with red/blue
glasses to get a
dramatic sense of the crater's
dimensions -- one mile wide, and up to 570 feet deep.
(A cross-eyed stereo pair is
available here.)
Historically, this crater is the
first recognized to
be caused by an impact rather than a volcanic eruption.
Modern
research indicates that the impactor responsible,
a 300,000 ton nickel-iron
meteor, struck some 50,000 years ago.
Estimates suggest that it was about 130 feet across and was
traveling over 26,000 miles per hour.
For comparison, the asteroid or comet impactor
that created the
Chicxulub crater 65 million years ago,
and is thought to have caused the extinction of the dinosaurs,
was 6 to 12 miles across.