Solar System all have impact craters and tectonic surface features, such as rift valleys and volcanoes. The term "inner planet" should not be confused with "inferior planet", which designates those planets that are closer to the Sun than Earth is (i.e. Mercury and Venus). Asteroids except for the largest, Ceres, are classified as small Solar System bodies and are composed mainly of refractory rocky and metallic minerals, with some ice. They range from a few metres to hundreds of kilometres in size. Asteroids smaller than one meter are usually called meteoroids and micrometeoroids (grain-sized), depending on different, somewhat arbitrary definitions. The asteroid
Minor planet Minor planet A minor planet is an astronomical object in direct orbit around the Sun (or more broadly, any star with a planetary system) that is neither a planet nor exclusively classified as a comet. Before 2006 the International Astronomical Union (IAU) officially used the term "minor planet", but during that year's meeting it reclassified minor planets and comets into dwarf planets and small Solar System bodies (SSSBs). Minor planets can be dwarf planets, asteroids, trojans, centaurs, Kuiper belt objects, and other trans-Neptunian objects. As of 2018, the orbits of 757,626 minor planets were archived at the Minor Planet Center,