What are Some Prominent Features of the Asteroid Belt?
The asteroid belt contains 98.5% of the solar system’s known asteroids, extending between about 2 astronomical units (AU, or Earth-Sun distances) to 3.3 AU from the Sun. It contains between 700,000 and 1.7 million asteroids over 1 km in diameter, but its total mass is only about 4% of the Moon. The asteroid belt contains a dwarf planet 900 km in diameter, Ceres, and three large asteroids, Vesta, Pallas and Hygiea, with an average diameter of 450 km. These bodies collectively make up half the mass of the asteroid belt. The asteroid belt exists because the orbits there are extremely stable, determined primarily by gravitational interactions between the Sun and Jupiter. The remaining majority of the protoplanetary disc either became planets, fell into the Sun, or have been ejected in eccentric orbits as comets. Another stable area is the Kuiper belt, located outside the orbit of Neptune, safe from being swept up by the gas giants. Contrary to depictions in fiction, the asteroid belt looks
