Meteor Crater (Barringer Crater)
The first crater on Earth shown to have been made by an impact.
Key facts
- When
- about 50,000 years ago
- Where
- Near Winslow, Arizona, United States
- What hit
- an iron meteoroid about 30 to 50 m across
- Era
- In the age of humans
- Location
- 35.03° N, 111.02° W
About 10 megatons of TNT, with published estimates ranging from a few to about 20 megatons.
Hundreds of times the Hiroshima bomb; similar to Tunguska, but the iron reached the ground.
What happened
Meteor Crater is a bowl about 1.2 km across and 170 m deep in the desert of northern Arizona. Pieces of iron meteorite, now called Canyon Diablo, lay scattered around it in their thousands.
In the early 1900s the mining engineer Daniel Moreau Barringer argued that a giant iron meteorite had made the crater, and spent years drilling in the hope of finding the buried mass. He never found it, because most of the iron had been vaporised, melted or shattered on impact. In 1960 Eugene Shoemaker's detailed study of the crater, and the discovery there of the high-pressure minerals coesite and stishovite, settled the matter.
Models suggest the iron broke up partly in the air and hit the ground at about 12 to 13 km per second.
Effects
The blast would have flattened everything within several kilometres. The area was then cooler and wetter, with woodland and grassland and animals such as mammoths and giant ground sloths, but people had not yet reached the Americas.
The evidence
Iron meteorites and melted droplets of iron around the crater, shocked quartz, coesite and stishovite, and rock layers turned upside down at the rim.
Did you know?
Apollo astronauts trained at Meteor Crater before going to the Moon.
The crater is privately owned and is still owned by the Barringer family's company.
Related pages
How is impact energy measured? See energy explained, or try the impact calculator.