Meteor Crater facts for kids
Meteor Crater
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| Impact crater/structure | |
|---|---|
| Confidence | Confirmed |
| Diameter | 0.737 miles (1.186 km) |
| Depth | 560 feet (170 m) |
| Rise | 148 feet (45 m) |
| Impactor diameter | 160 feet (50 m) |
| Age | 50,000 years |
| Exposed | Yes |
| Drilled | Yes |
| Bolide type | Iron meteorite |
| Location | |
| Location | Coconino County |
| Coordinates | 35°01′41″N 111°01′24″W / 35.02806°N 111.02333°W |
| Country | United States |
| State | Arizona |
 Meteor Crater
Location in Arizona
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| Access | Interstate 40 |
| Designated: | November 1967 |
Meteor Crater, also known as Barringer Crater, is a famous impact crater in the desert of northern Arizona, United States. It's about 37 mi (60 km) east of Flagstaff and 18 mi (29 km) west of Winslow. The pieces of the meteorite that formed it are called the Canyon Diablo Meteorite.
This amazing crater sits 5,640 ft (1,719 m) above sea level. It's about 3,900 ft (1,200 m) wide and 560 ft (170 m) deep. A rim rises 148 ft (45 m) above the flat land around it. The bottom of the crater is filled with 690–790 ft (210–240 m) of rocky debris. The crater has a somewhat square shape, which scientists think is due to natural cracks in the rocks where it hit.
Even though it's a very important natural site, the crater is still owned by the Barringer family. Many science groups, like the Lunar and Planetary Institute, call it the "best-preserved meteorite crater on Earth." In November 1967, it was named a National Natural Landmark.
Contents
How Meteor Crater Formed
Meteor Crater was made about 50,000 years ago during the Pleistocene ice age. At that time, the climate in this part of Arizona was much cooler and wetter. The area was a grassy plain with some trees, where huge animals like mammoths and giant ground sloths lived.
The object that dug out the crater was a nickel-iron meteorite, about 160 ft (50 m) wide. Scientists have debated how fast it hit. Early ideas suggested it hit at 20 km/s (45,000 mph), but newer research says it was slower, around 12.8 km/s (29,000 mph). About half of the meteorite probably turned into gas as it flew through the air.
The impact was incredibly powerful, like 10 megatons of TNT. Most of the meteorite vaporized (turned into gas) when it hit, so very little of it was left in the crater.
Since the crater formed, its rim has lost about 50–65 ft (15–20 m) of its height due to natural erosion. Also, about 100 ft (30 m) of new dirt and lake sediments have filled the bottom. Many other impact craters on Earth have been worn away by weather and geology. But because Meteor Crater is relatively young and Arizona has a dry climate, it has stayed almost the same since it was made. This great preservation helped scientists realize it was an impact crater.
Discovering and Studying the Crater
Scientists became interested in Meteor Crater after American settlers found it in the 1800s. It had many early names, like "Coon Mountain" and "Meteor Mountain." Daniel M. Barringer was one of the first to suggest it was made by a meteorite. His family later bought the land in the early 1900s, which is why it's also called "Barringer Crater." The meteorites found nearby are called Canyon Diablo meteorites.
At first, people thought the crater was made by a volcanic steam explosion. This was because the San Francisco volcanic field is only about 40 mi (64 km) to the west.
Early Scientific Views
In 1891, a scientist named Albert E. Foote wrote the first paper about the meteorites found in Northern Arizona. He recognized an iron rock as a meteorite and led a trip to find more pieces. His team found many samples, some weighing over 600 lb (270 kg). Foote even found tiny diamonds in the meteorites. His paper was the first to describe Meteor Crater to the scientific world.
Later that year, Grove Karl Gilbert, a chief geologist, studied the crater. He thought it was from a volcanic steam explosion. Gilbert believed that if it were an impact crater, a huge amount of meteorite material should still be buried there. But he found no strong magnetic signals, which would have shown a large buried meteorite. He also thought the amount of rock dug out of the crater matched the amount piled on the rim, meaning no meteorite was left. Gilbert was one of the first to suggest that the Moon's craters were also made by impacts, not volcanoes.
Daniel M. Barringer's Work
In 1903, a mining engineer named Daniel M. Barringer said the crater was made by a large iron meteorite. His company bought the land, hoping to mine the valuable metal he thought was buried there. He estimated the meteorite weighed 100 million tons and could be worth over a billion dollars in 1903 money. Barringer spent a lot of his own money, about $500,000 (which is like $7 million today), trying to find this metal.
Many scientists were doubtful at first. Back then, people thought craters on the Moon were volcanic, and no impact craters were known on Earth. Barringer kept trying to prove his idea by looking for the meteorite's remains. About 30 tons of meteorite fragments were found around the crater. This made Barringer think the main part of the meteorite was still underground.
However, people didn't understand much about how impacts worked back then. Barringer didn't know that most of the meteorite would have turned into gas when it hit. He drilled down 1,375 ft (419 m) for 27 years, but he never found a large deposit of meteorite iron.
In 1929, an astronomer named F.R. Moulton studied the impact. He figured out that the meteorite probably weighed much less, around 300,000 tons. He also concluded that the impact would have created enough heat to instantly vaporize the meteorite. Daniel M. Barringer died just ten days after Moulton's report came out. By this time, most scientists had started to agree with the idea that the crater was formed by an impact.
Harvey H. Nininger's Contributions
Harvey Harlow Nininger was an American scientist who studied meteorites. In the 1930s, he helped bring new interest to meteorite research. He wrote a book explaining how Meteor Crater was formed when an asteroid hit Earth. In 1942, Nininger moved his home and business to the "American Meteorite Museum" near the crater.
He did a lot of research at the crater, finding new things like "impactite" (rock melted by the impact) and tiny iron-nickel balls from the vaporized asteroid. Nininger's work greatly helped scientists accept that Meteor Crater was formed by an asteroid impact. Many of his discoveries were later seen at other impact craters around the world.
Nininger believed the crater should be a national monument. He even tried to get the government to buy it from the Barringer family. This made the Barringers upset, and they stopped him from doing more research at the crater. A few years later, in 1953, the Barringer family opened their own private museum on the crater rim.
Eugene M. Shoemaker's Discoveries
Eugene Merle Shoemaker continued studying the crater. He made a key discovery: two rare minerals called coesite and stishovite. These minerals are only found when rocks containing quartz are hit with extreme, sudden pressure, like from an impact or a nuclear explosion. Volcanic activity cannot create them.
In 1960, Shoemaker confirmed that these minerals were at Meteor Crater. This added strong proof that the crater was formed by an impact that created incredibly high temperatures and pressures. He also confirmed that most of the meteorite vaporized upon impact. The smaller pieces of the Canyon Diablo meteorite found around the site broke off before or during the impact.
Shoemaker's work, along with studies of craters made by nuclear tests, helped scientists figure out the energy of the meteorite impact.
Geology of the Crater
The impact turned the layers of rock around the crater upside down. If you climb the rim from the outside, you'll find the rock layers in reverse order from how they normally appear. For example, the oldest rock layer, Coconino Sandstone, is at the top of the rim. Below it are the Toroweap Formation and Kaibab Formation, and then the Moenkopi Formation at the very bottom of the outer rim.
The soil around the crater is brown and rocky.
Recent History and Tourism
During the 1960s and 1970s, NASA astronauts trained in Meteor Crater to get ready for the Apollo missions to the Moon. Astronaut training still happens there today.
In 1964, a small plane crashed inside the crater. The pilots flew too low and couldn't climb out. Both pilots were hurt but survived. A small part of the plane's wreckage can still be seen.
Meteor Crater is a popular place for tourists, with about 270,000 visitors each year. The Barringer family company still owns it. It's also an important place for education and scientific research.
The Meteor Crater Visitor Center is on the north rim of the crater. It has fun, interactive exhibits about meteorites, asteroids, space, the Solar System, and comets. You can see an Apollo command module and a 1,406 lb (638 kg) meteorite found nearby, and even touch meteorite samples. The Visitor Center also has a movie theater, a gift shop, and places to view the crater. Guided tours of the rim are offered daily, if the weather is good.
See also
- Barringer Medal
- List of impact craters on Earth
