Asteroid

Rare card · No. 43440

An asteroid is a minor planet that orbits within the inner Solar System or is co-orbital with Jupiter (Trojan asteroids). These objects are larger than a meteoroid (thus 1 meter or larger) and are neither a planet nor an identified comet. Asteroids are rocky, metallic, or icy bodies with no atmosphere, and are broadly classified into C-type (carbonaceous), M-type (metallic), or S-type (silicaceous). The size and shape of asteroids vary significantly, ranging from small rubble piles under a kilometer across to Ceres, a dwarf planet almost 1000 km in diameter. A body is classified as a comet, not an asteroid, if it shows a coma (tail) when warmed by solar radiation, although recent observations suggest a continuum between these types of bodies. Of the roughly one million known asteroids, the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 astronomical units (AU) from the Sun, in a region known as the main asteroid belt. The total mass of all the asteroids...

Read on Wikipedia · Image 243_ida.jpg: NASA/JPL derivative work: Chzz ►, Public domain