Other forms: meteoroids
A meteoroid is a small space rock moving through the solar system. Though space may seem empty, millions of tons of meteoroids, ranging in size from tiny dust particles to small boulders, orbit the Sun.
Most meteoroids are about the size of pebbles; they're fragments of larger, rocky asteroids or icy comets. Some are dust-sized particles, smaller than a grain of sand, and others are boulder-sized objects, about a meter across. Some meteoroids are chunks blasted off of larger bodies like the Moon or the planet Mars! If a meteoroid enters Earth's atmosphere, it becomes a meteor, or shooting star. If any part of that object survives the trip through the atmosphere and hits Earth's surface, it's called a meteorite. Of course, the vast majority of meteoroids continue orbiting the Sun and never encounter Earth at all.