Meteorite

A meteorite is a piece of rock that is generally detached from an asteroid that passes through the Earth’s atmosphere and survives impact with the ground. Most originate in larger bodies of asteroids reside in the belt of asteroids between Mars and Jupiter. Collisions and gravitational interactions send these pieces of asteroids into the inner solar system forcing them to travel to Earth. Some of these meteorites are the brightest shooting stars we can see at night.

Characteristics

The main characteristics of meteorites are the following:

• They are masses of irregular shape , can be angular or square and generally have rounded corners.
• Some will be marked on their surface with pits that are commonly called fingerprints .
• The iron in meteorites is always alloyed with nickel .
• Sometimes the number of falling meteorites increases dramatically, and these events are called meteor showers .
• Those found on Earth are about the size of a fist, but some are larger than a building.
• The word meteor means ” sky phenomenon ” and is used to describe the light produced when a piece of matter from space enters the atmosphere.
• To enter the atmosphere at an average speed of around 10 and 70 km / s.

History

In reality, meteorites did not attract much serious scientific attention during the first centuries of the Enlightenment because they were explained as atmospheric processes , hail showers condensed in clouds, or terrestrial rocks struck by lightning, or that they were volcanic rocks, thrown violently during major eruptions. Nobody thought that meteorites were rocks from space. At the beginning of the 19th century, scientists shared Isaac Newton’s opinion that small objects could not exist in interplanetary space.

At the end of the 18th century there was a change and in 1772, during one of his trips the German naturalist Peter Pallas examined a huge mass of iron near Krasnojarsk , which had fallen from the sky. It caught his attention because it was covered with a black crust , and there were many crystals of olivine translucent in its parent. Unconsciously, he had discovered a new type of meteorite, a class of stony iron meteorites that would later receive his name: pallasites .

On December 13, 1795, a stone weighing about 25 kg fell at Wold Cottage , England in broad daylight, contradicting explanations for the formation of meteorites. This meteorite was analyzed by Edward Howard , who discovered that it contained iron and nickel metal grains , similar in composition to the iron meteorites described in Chladni’s book . In 1802, Howard published the results of his analysis and his conclusions regarding the Wold Cottage incident, convincing a growing number of scientists that meteorites actually represent extraterrestrial matter falling from the sky .

The study and analysis of meteorites began in 1768 when one of them fell in Lucé , France . After the fall, the French Academy of Sciences sent a group of scientists to study the meteorite.

Types of meteorite

There are three basic types of meteorites, those of iron, stone and stone iron. Each of them is explained below.

• Iron or metallic meteorites : formed of solid nickel iron . Due to the strength of iron, most of the individual meteorites are iron, and many of the craters were formed by these types of meteorites. They show a pattern when etched with chemicals due to the different iron nickel minerals that make them up.
• Stony meteorites : they are made of stone almost entirely and are the most common, about 10% of them fall to the ground. Within this group we can find, for example, the stony meteorites , chondrites , achondrites and planetary meteorites that are also achondrites but have unique origins.
• Stony-metallic meteorites : they are made up of a mixture of iron , nickel and some silicate minerals . They are divided into two groups, the pallasitas and the mesosideritas

Components (edit)

Depending on the type of meteorite, these can be composed of silicate , aerolite or lithite, many of them have iron and nickel , metallic and rocky materials .

How is a meteorite different from an asteroid?

The asteroid is a rocky , carbonaceous or metallic body, smaller in size than a planet and larger than a meteoroid . The meteorite is a rocky body that reaches the surface of a planet , leaving a trail of light .

Meteorite fall on earth

The largest that has fallen and has been identified on Earth was found in 1920 in Namibia and was called the Hoba meteorite . It was 2.7 meters wide and its approximate weight was about 60 tons and it was composed of iron and nickel .

A very large asteroid impact 65 million years ago, which created the 300-kilometer-wide Chicxulub crater in the Yucatan Peninsula , is believed to have contributed to the extinction of about 75% of land and marine animals on Earth in the moment, including dinosaurs.One of the most intact craters is the Barringer Meteorite Crater in Arizona , approximately 1 kilometer in diameter, formed by the impact of an iron – nickel metal meteorite approximately 50 meters in diameter. It is 50,000 years old and is so well preserved that it has been used to study the processes of impact . Since this feature was recognized as an impact crater in the 1920s, about 170 impact craters have been identified on Earth.

Meteorite Fragments

Many meteorite fragments have been found around the world and they are generally sold for large sums of money as some are even millions of years old .

Curiosities

Meteor showers are usually named after a star or constellation that is close to where meteors appear in the sky. Perhaps the most famous are the Perseids , which peak around August 12 of each year. Each Perseid meteorite is a small piece of Comet Swift-Tuttle , which swings through the Sun every 135 years.