The Asteroid belt, also known as the Main belt, is a three billion cubit-mile asteroid region in the Solar System located between the two planets Mars and Jupiter, and contains a moderate fraction of the asteroids that are found in the Solar System. Not only does this belt contain asteroids, but it also is home to numerous dwarf planets such as Ceres, the dwarf planet closest to our Solar System. This belt is constantly orbiting the Sun, along with the planets.
The asteroid belt's formation is hypothetical. Astronomers do not know the exact way the asteroid belt was created, yet several theories surround the possible formation of this belt.
In 1802, Heinrich Olbers, the discoverer of Pallas, made a suggestion to William Herschel, the discoverer of Uranus, that fragments from a much larger planet after an impact created the Asteroid belt. Astronomers believe that all of the asteroids in the Asteroid belt wouldn't even have the mass of the Earth's moon, so astronomers believe that this was a relatively small planet made from either gas or rock.
Kirkwood gaps were discovered by Daniel Kirkwood in 1857. These are gaps that are caused by asteroids that have the same orbital period, or amount of time taken to orbit the Sun once. When the planet that formed the Asteroid belt was destroyed, some asteroids and fragments were shipped off into deep space, causing these "Kirkwood Gaps".
The composition of the asteroid belt varies depending on the distance at which the asteroids formed from the Sun. These distances bring us three distinct categories of asteroids that exist in this belt: carbonaceous, the most populous, metal-rich asteroids, and silicaceous asteroids.
- Carbonaceous asteroids, also known as C-type asteroids, are the most populous asteroids in the asteroid belt. These asteroids appear much more darker than other asteroids. Carbonaceous asteroids are made up of clay and silicate rocks. These the oldest category of asteroids to exist in our solar system.
- Silicaceous asteroids, also known as S-type asteroids, on the other hand, are made up of silicate rocks and nickel-iron. These are typically lighter than carbonaceous asteroids.
- Metallic asteroids, also known as M-type asteroids, make up the least portion of the asteroid belt. These are mainly made up of mainly nickel-iron. These are the lightest of the asteroids.
Groups of AsteroidsEdit
Just as they sound, the Jupiter Trojans are the section of asteroids that orbit the Sun near, around, or even on the exact orbit of Jupiter. The ones not directly on the orbit are around sixty degrees from on the other side of Jupiter. The Trojans make one orbit in 11.8 years, similar to that of Jupiter's 11-year orbit.
Near Earth AsteroidsEdit
Though not their formal name, near Earth asteroids follow the orbit of, around, or even travel inside the orbit of the Earth. Mainly referred to as the Apollo, Aten, and Amor asteroids, these are believed to have future impacts with the Earth within the next hundred thousand to million years. These make orbits within the ranges of Earth and Mars' orbital periods.
There are bodies located outside of the belt that are shown to have cometary action, or comet-related activity. Main-belt comets are thought to have been a major component in the creation of the Earth's oceans. They are shown to have high amounts of a substance known as deuterium-hydrogen, which cannot be found in regular comets.
Near-Earth objects are asteroids in the Asteroid belt that have collided together and compacted together to form a meteor. This meteor is then sent on a collision-course with Earth and collides with Earth or are disintegrated inside of the atmosphere before it hits the surface.
- Main article: Ceres
Ceres is the only celestial object to be a dwarf planet and an asteroid. In fact, it is the only dwarf planet located in the Asteroid belt. In fact, it maintains hydrostatic equilibrium, which means it is barely massive enough to have even a trace gas in an atmosphere.