Asteroidivööl

Asteroidivööl is a Finnish term that translates to "asteroid belt." It refers to the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter. This region is populated by a great number of irregularly shaped bodies called asteroids or minor planets. The total mass of the asteroid belt is estimated to be about 4% of the Moon's mass. Ceres, the largest object in the belt, accounts for about a third of the total mass. The remaining asteroids vary in size, from hundreds of kilometers in diameter to dust particles.

The asteroid belt is not a densely packed region as often depicted in science fiction. The distances between individual asteroids are vast, making collisions rare. However, the gravitational influence of Jupiter plays a significant role in shaping the belt, creating gaps known as Kirkwood gaps where the orbital periods of asteroids are in simple resonance with Jupiter's period. These resonances can perturb asteroids out of the belt, some of which may eventually cross Earth's orbit. The study of asteroids provides insights into the early history of the Solar System, as they are remnants from the formation of the planets that did not coalesce into larger bodies.