Meteorite Classification – Definition & Detailed Explanation – Planetary Science Glossary

I. What is a Meteorite?

A meteorite is a solid piece of debris from an object, such as a comet or asteroid, that has survived its passage through the Earth’s atmosphere and landed on the Earth’s surface. These objects are often referred to as “shooting stars” or “falling stars” when they are seen streaking across the night sky. However, only a small percentage of these objects actually make it to the Earth’s surface as meteorites.

Meteorites are typically made up of rock, metal, or a combination of both. They can vary in size from tiny grains to massive boulders weighing several tons. When a meteorite lands on Earth, it is often accompanied by a bright flash of light and a loud explosion known as a meteorite fall.

II. How are Meteorites Classified?

Meteorites are classified based on their composition, structure, and origin. The three main types of meteorites are stony meteorites, iron meteorites, and stony-iron meteorites. These classifications are further broken down into subtypes based on specific characteristics.

Meteorites are also classified based on their chemical composition, isotopic composition, and mineralogy. Scientists use a variety of analytical techniques, such as spectroscopy and microscopy, to study meteorites and determine their classification.

III. What are the Three Main Types of Meteorites?

1. Stony Meteorites: Stony meteorites are the most common type of meteorite and are made up of silicate minerals. They are further classified into two subtypes: chondrites and achondrites. Chondrites are primitive meteorites that have not undergone significant geological processing, while achondrites are meteorites that have been modified by geological processes.

2. Iron Meteorites: Iron meteorites are composed primarily of iron and nickel. They are believed to originate from the cores of asteroids that were once molten. Iron meteorites are often dense and metallic in appearance.

3. Stony-Iron Meteorites: Stony-iron meteorites are a combination of both stony and metallic components. They are believed to originate from the boundary between the core and mantle of differentiated asteroids. Stony-iron meteorites are rare and are often highly prized by collectors.

IV. What are the Subtypes of Meteorites?

In addition to the three main types of meteorites, there are several subtypes that are based on specific characteristics. Some of the subtypes of meteorites include:

1. Carbonaceous Chondrites: Carbonaceous chondrites are a subtype of chondrite meteorites that contain high levels of carbon and organic compounds. These meteorites are thought to be some of the most primitive objects in the solar system and may provide insights into the origins of life on Earth.

2. Lunar Meteorites: Lunar meteorites are meteorites that have been found on Earth and are believed to have originated from the Moon. These meteorites provide valuable information about the geology and history of the Moon.

3. Martian Meteorites: Martian meteorites are meteorites that have been found on Earth and are believed to have originated from Mars. These meteorites have provided scientists with valuable information about the geology and climate of Mars.

V. How are Meteorites Named?

Meteorites are typically named after the location where they were found. For example, the Canyon Diablo meteorite was found near Canyon Diablo in Arizona. Meteorites can also be named after the type of meteorite they are, such as the Allende meteorite, which is a carbonaceous chondrite.

In some cases, meteorites are named after the person who discovered them or after a significant event associated with their discovery. For example, the Tunguska meteorite was named after the Tunguska River in Siberia, where a massive meteorite explosion occurred in 1908.

VI. What is the Significance of Meteorite Classification in Planetary Science?

Meteorite classification is essential in planetary science as it provides valuable insights into the formation and evolution of the solar system. By studying the composition and structure of meteorites, scientists can learn about the processes that occurred during the early stages of planetary formation.

Meteorites also provide clues about the conditions present in the early solar system and the types of materials that were present. By studying meteorites, scientists can gain a better understanding of the origins of planets, asteroids, and other celestial bodies.

In addition, meteorites can provide information about the history of the Earth and other planets in the solar system. By studying meteorites, scientists can learn about the impact events that have shaped the surfaces of planets and the processes that have influenced their evolution over time.

In conclusion, meteorites are fascinating objects that provide valuable insights into the history and evolution of the solar system. By studying meteorites and classifying them based on their composition and structure, scientists can learn more about the processes that have shaped the planets and other celestial bodies in our solar system. Meteorites are not only important for understanding the past but also for predicting the future and potentially protecting the Earth from potential impact events.