Films about meteoroids, small rocky or metallic bodies in outer space. Meteoroids are distinguished as objects significantly smaller than asteroids, ranging in size from grains to objects up to 1 m (3 ft 3 in) wide. Objects smaller than meteoroids are classified as micrometeoroids or space dust. The visible passage of a meteoroid, comet, or asteroid entering Earth's atmosphere is called a meteor, and a series of many meteors appearing seconds or minutes apart and appearing to originate from the same fixed point in the sky is called a meteor shower.