What is the Largest Impact Crater in the Solar System?

A meteorite crater (larger crater, also known as a crater) is a circular crater formed by the impact of a meteorite on the surface of a planet, satellite, asteroid or other celestial body. A center cone may form at the center of a crater greater than 4 km in diameter. The crater may be filled with water due to rainfall and other reasons, forming an impact lake.

Crater

The condition for the formation of a crater on the earth is that an object collides with the earth from outer space at a speed of 11.6 km / s. In this process, the kinetic energy of this object is converted into thermal energy, and the energy released by the heavy meteorite can reach the energy equivalent to that released by the explosion of thousands of tons of TNT. This energy level is equivalent to

Based on the actual investigation of the crater site and the study of the impact effects of the main rock-forming minerals, the results of the nuclear explosion and artificial impact simulation experiments were combined. The main signs of judging the crater are:

Meteor craters are generally circular structures. The detection results of dozens of craters on the surface show that they are mostly circular structures.

Find the basis for the hypothesis of meteorite bombardment in the formation of circular craters and craters on the surface of the Earth's moon, Mercury, Mars and its satellites, and determine the existence time and distribution of craters. At the same time, to study the impact of huge meteorite on the formation of the earth and other planets, the influence of the original heat and the rotation of the rotation axis, and to study

There are relatively few craters found on Earth. This is because

Chert crater

In July 2010, the authoritative international academic journal "Earth and Planetary Science Letters" was published

Two craters in southwestern France

Both craters in the southwest are between 200 and 300 kilometers in diameter, and the distance between them is only 140 kilometers. The two craters may have been the product of a collision with the same asteroid 200 million years ago. This may be the largest asteroid hitting Earth to date.

Crater in Arizona, USA

Crater in Arizona, Nevada, USA. This crater was the result of an iron meteor with a diameter of about 30-50 meters hitting the ground 50,000 years ago. The meteor weighs about 500,000 kilograms and has a speed of 20 kilometers per second. Its explosive force is equivalent to 20 million kilograms of TNT (TNT), which is more than 1,000 times that of the US bombing of Hiroshima. The explosion created a large pit on the ground with a diameter of about 1,245 meters and an average depth of 180 meters. It is said that 20 pits can be placed in the pit, and the surrounding stands can accommodate more than 2 million spectators.

Yucatan Crater, Mexico

The crater of the Chiquezulla crater in Yucatan, Mexico, has a diameter of 198 kilometers. The perpetrator was a small celestial body 10 to 13 kilometers in diameter 65 million years ago. The crater was buried under 1100 meters thick limestone. It was first discovered by oil prospectors and then confirmed by the space shuttle Endeavour through remote sensing technology.

Tunkulas Crater, Russia

Meteorites are found in Tunguska, Siberia, Russia. On June 30, 1908, witnesses saw a fireball wading across the sky from south to north, disappearing beyond the horizon, and then a flame rose and a huge explosion sounded on the horizon. In the days after the explosion, the sky in Tunguska was shrouded in gloomy orange, and large areas continued to have white nights. Investigators believe it was an explosion caused by a meteorite hitting Siberia. It is speculated that this asteroid or comet fragment with a diameter of less than 60 meters broke into the atmosphere and exploded 8 kilometers above the ground. On February 12, 1947, a big explosion similar to Tunkulas occurred in the Russian Far East city of Sihot, and more than 100 craters were found. More than 8,000 nickel-iron meteorite were collected with a total weight of more than 28 tons.

Meteorites and craters in China

In 1490, there were records that 10,000 people were killed by meteorite rain in China. About 200 kilometers north of Beijing, the Inner Mongolia Duolun area, where there is a super-large pit-like terrain, is most likely a crater. This pit has concentric annular "ridges", an outer ring with a diameter of 170 kilometers and an inner ring with a diameter of 70 kilometers. It was formed about 130 million years ago. On March 8, 1976, a large-scale meteorite rain occurred in the suburbs of Jilin City, Jilin Province, China. The diameter of the meteorological fall area was more than 70 kilometers, and the area was between 400 and 500 square kilometers. More than 100 meteorites were collected. 2616 kg, of which "Jilin No. 1" meteorite weighs 1770 kg, which is the largest stone meteorite in the world.

Gosses Bluff

Australian explorer Goss discovered Goss cliffs in 1873. The first people to visit this crater were the indigenous people living in the Australian desert, and the site of the camp in the pit left traces of their activities that year. Like most similar craters, Goss cliffs have geological fractures that radiate from the center to the surroundings. According to scientists' research on the formation of this pit, it was confirmed that it was formed 130 million years ago from an impact from space. The impact of the object was extremely fast, but the density was relatively low. Ice and dust) rather than asteroid meteorites.

The original crater was about 20 kilometers in diameter, and the pit surrounded by Goss cliffs was only 4 kilometers in diameter. It was a central pit. The periphery has been eroded in the long years of hundreds of millions of years. At the outer edge of the pit were two hard sandstone cliffs, one hundred and eighty meters above the plain ground, which also formed during that comet impact. Underground exploration shows that the same rock formation is at a depth of two kilometers underground, and it is conceivable how strong the impact was that year.

Antarctica

Some scientists have suggested that there is a crater with a diameter of 240 kilometers and a depth of 800 meters under the ice near the poles of the Antarctic continent. Six to 700,000 years ago, a small celestial body hit the earth from here, and the direction of the earth's axis and the rotation speed of the earth changed accordingly. Researchers have found and recovered 23,000 meteorite samples on the Antarctic ice sheet.

Kara Kul crater, Tajikistan

This crater, near the border with Afghanistan, formed about 10 million years ago on the Pamirs and has a diameter of 45 kilometers.

Canadian Clearwater Lakes Crater

These are a pair of twin craters that formed 290 million years ago and may have been formed by the simultaneous impact of asteroids that split into two. The crater is 32 kilometers in diameter to the west and 22 kilometers in diameter to the east.

Manicouagan crater in Canada

The crater has a clear ring-shaped lake covered by ice. This crater has a diameter of 100 kilometers and was formed 210 million years ago.

Walf Creek crater, Australia

Located in the center of the northern desert. 875 meters in diameter, formed 300,000 years ago, is a relatively young crater. The height of the side of the pit is 25 meters, and the center depth of the pit is 50 meters. In the crater, there are still residues of iron meteorite oxidation and glass objects formed by melting sand particles at high temperature.

Spider crater

Located in Western Australia, the crater cone found in the center of this crater has limited the age of spider craters to some extent, although there is still a lot of uncertainty in this value. NASA believes that the impact event that formed this crater occurred about 900-600 million years ago in the Neoproterozoic period, when the earth was experiencing a severe freezing period, and was called "snowball earth" by geologists. . ^[5]

Aorounga Crater on Lake Chad, Africa

It is 17 kilometers in diameter and was formed 200 million years ago.

Roter Kamm crater in Namibia

2.5 kilometers in diameter, formed 5 million years ago.

Craters of Germany

With a history of 15 million years, it is already a lush farmland.

Vredefort crater in south africa

Its diameter has reached more than 30,000 meters, and its age is about 2 billion years.

Dinosaur Crater

Dinosaurs are the largest terrestrial vertebrates ever seen on the planet. The mystery of their sudden extinction seems to have been slowly unveiled. The reason may be that an asteroid hit Mexico's Yucatan Peninsula 65 million years ago. Recent computer simulations in the United States also show this. It was not until 12 years ago that this huge crater was discovered. Since December 2001, the Geographic Research Center of Potsdam, Germany has begun research in this area. The celestial body may have hit a crack several kilometers deep on the surface of the earth with the impact of 10 billion atomic bombs. The impacted debris was scattered, causing strong earthquakes, tsunamis, floods and fires. A large amount of dust and gas produced by the collision were mixed into the atmosphere, blocking the sun and making the climate abnormal. First the fire, then the glacial period, and then the unbearable heat. The ecological catastrophe caused the extinction of flora and fauna, including dinosaurs.