Meteorite, also known as "meteorite", is an unburned stone, iron or stone that breaks away from the original orbit of the cosmic meteor or dust fragments that quickly scatter to the surface of the earth or other planets A substance mixed with iron.
Introduction to Meteorites
Because meteorites are objects from outer space, the authenticity of meteorites requires instrument identification, and the naked eye only plays an auxiliary role. Most meteorites come from the asteroid belt between Mars and Jupiter, and a small number come from the moon and Mars. Meteorites can be roughly divided into stony meteorites, iron meteorites, and stony-iron mixed meteorites.
The average density of meteorites is between 3 and 3.5, and the main component is silicate . The density of meteorite is 7.5 to 8.0, and it is mainly composed of iron and nickel. The composition of meteorite is between the two, and the density is between 5.5 and 6.0. Meteorites have different shapes. The largest meteorite is the Jilin No. 1 meteorite weighing 1,770 kilograms. The largest meteorite is the Goba meteorite in Namibia, which weighs about 60 tons. The crown of Chinese meteorites is the "silver camel" found in Qinghe County, Xinjiang, which weighs about 28 tons.
More than 40,000 meteorite samples have been collected around the world, with various styles. They can be roughly divided into three categories: stony meteorite (the main component is silicate), iron meteorite (iron-nickel alloy) and stony iron meteorite (mixture of iron and silicate).
Meteorites refer to the remains of meteorites that fell to the ground. They are composed of iron, nickel, silicate and other minerals, and are also called meteorites. Also refers to meteorites that contain more stone or are entirely stone. A large amount of organic compounds such as ammonia, nucleic acids, fatty acids, pigments, and 11 kinds of amino acids are also found in meteorites with high carbon content. Therefore, people believe that the origin of life on earth has a considerable relationship with meteorites.
People discovered during observation that there is an asteroid belt between the orbits of the planets in the solar system, Mars and Jupiter, which is the hometown of meteorites. These asteroids are running in their own orbits and constantly colliding, and sometimes they are It crashes out of orbit and heads towards the earth. When it enters the atmosphere, it rubs against it and emits light and heat, which is a meteor. When a meteor enters the atmosphere, the high temperature, high pressure and internal imbalance generated cause it to explode, forming a meteor shower. What was not burned out fell to the earth and became meteorites. People have successively discovered a crater 170 meters deep and 1,240 meters in diameter in Arizona, the United States. There is also a large crater in Antarctica with a diameter of 300 kilometers. A giant impact crater with a diameter of more than 1,000 kilometers was discovered in the middle of the Atlantic Ocean.
Scientists say that our earth receives 50,000 tons of such "gifts" every day. Most of them burn out at an altitude of 10 to 40 miles above the ground, and are difficult to find even if they fall on the ground. They move in the universe, and because they have no other protection, they are directly exposed to radiation and catastrophes from various cosmic rays, and their own radioactive heating cannot cause them to undergo major changes. So its own record is reliable. Its research scope covers a wide range of fields, such as high-energy physics, celestial evolution, geochemistry, and the origin of life.
The largest preserved iron meteorite in the world is the Hoba iron meteorite in Namibia, Africa, which weighs about 60 tons. The second is the Greenland iron meteorite No. 1, which weighs about 33 tons. The Xinjiang iron meteorite in my country weighs about 28 tons and is the third largest iron meteorite in the world. The largest stony meteorites in the world are the Jilin meteorite , with a total weight of 2,550 kilograms of the collected samples. The Jilin No. 1 meteorite, weighing 1,770 kilograms, is the largest stony meteorite block that has been collected by humans.
In addition, there is a kind of meteorite called " glass meteorite ". It is black or dark green, somewhat like stone, but not stone. It's a bit like glass, but it's a very special glassy substance that doesn't crystallize. It comes in various shapes, is generally not large, and weighs from a few grams to dozens of grams. The identification of tektites mainly depends on the place where the sample was found and its chemical isotope characteristics, with the chemical isotope characteristics as the final basis. So far, hundreds of thousands of suspected tektites have been discovered, and what is strange is that their distribution is obviously regional, and the cause of the regional appearance has not yet been determined.
Features
Meteorites are burned and abraded in the atmosphere, and their shapes are mostly round without edges or corners.
- Melting craters: The surface of meteorites is covered with pits of varying sizes and depths, namely melting craters. Many meteorites also have shallow and long air marks, which may be left by the falling off of low-melting point minerals.
- Molten crust: When a meteorite passes through the atmosphere, the extremely high temperature causes the surface of the meteorite to melt, producing a micron to millimeter-level glassy layer, which is the molten crust. When a meteorite exists on the surface for a long time, its molten crust is easily weathered and disappears.
- Specific gravity: Because meteorites contain iron and nickel, the specific gravity can be up to 8. Stone meteorites also often contain 20 iron and nickel, so they have a larger specific gravity than ordinary rocks. However, there are a very small number of stony meteorites (such as carbonaceous chondrites , etc.) that contain no or extremely low metal content, and their density is similar to that of ordinary earth rocks.
- Magnetism: Various meteorites have magnetism of varying strengths because they contain iron. Weathered meteorites are not magnetic and therefore are not considered meteorites.
- Streaks: Meteorites generally have no streaks or only light gray streaks when rubbed on unglazed porcelain plates, while the streaks of iron ore are black or brown-red, so as to distinguish them.
- If you also like meteorites, you can leave a message to get the contact information, and let us explore meteorites together! ! !
