Asteroids

Asteroids are small celestial bodies, especially those of the inner solar system. Those with the big ones are called planetoids. These terms have been historically applied to any astronomical object revolving around the Sun that has not shown the disk of a planet and has not been observed to have the characteristics of an active comet. Like the small planets in the Solar System they were discovered and found to have unstable surfaces that are similar to those of comets, they are usually found in the asteroid belt between Mars and Jupiter. In this article, the term "asteroid" refers to the small planets of the Solar System, including those co-orbiting with Jupiter.

There are millions of asteroids, which are leftovers within the solar nebula where the Sun was formed and did not grow enough to make planets. Most of the known asteroids orbits in the asteroid belt. However, other families exist with significant populations, including asteroids near the Earth. Individual asteroids are classified by their characteristic spectra, which are divided into three main groups: group-C, group-M, and gupi-S. These are named and generally identified in carbon, metal, and silicate (with stones), respectively. The magnitude of asteroids varies greatly, some reaching more than 1,000 km in diameter Asteroids are differentiated by comets and meteoroids. In the case of comets, the difference is in composition: while the asteroids are mainly composed of minerals and rock, comets are made up of dust and ice. The difference between asteroids and meteoroids is largely in size: Meteoroids have a diameter of less than one meter, while asteroids have a diameter of more than one meter. In the end, meteoroids may consist of both cometary or asteroid material.

Only an asteroid, known as the 4 Vesta, which has a relatively reflective surface, is usually visible from the naked eye, and this only in very dark sky when it is positively positioned. Rarely, small asteroids passing by the Earth can be visible with a naked eye for a short time