A meteor, sometimes called a shooting star or a falling star, is actually a space rock that is crashing through Earth's atmosphere. This meteor is streaking across the sky above Chelyabinsk, Russia, in 2013. A meteor is a streak of light in the sky caused by a meteoroid crashing through Earth's atmosphere.

Most meteoroids that cause meteors are about the size of a grain of sand, i.e. they are usually millimeter-sized or smaller.