A meteor shower is a celestial event in which a number of meteors are observed to radiate, or originate, from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller than a grain of sand, so almost all of them disintegrate and never hit the Earth's surface. Very intense or unusual meteor showers are known as meteor outbursts and meteor storms, which produce at least 1,000 meteors an hour, most notably from the Leonids. The Meteor Data Centre lists over 900 suspected meteor showers of which about 100 are well established. Several organizations point to viewing opportunities on the Internet. NASA maintains a daily map of active meteor showers.
Eta Aquariids meteor shower, with zodiacal light and planets marked and labeled
Diagram from 1872
Meteor shower on chart
Comet Encke's meteoroid trail is the diagonal red glow.
A meteoroid is a small rocky or metallic body in outer space.
Meteoroids are distinguished as objects significantly smaller than asteroids, ranging in size from grains to objects up to a meter wide. Objects smaller than meteoroids are classified as micrometeoroids or space dust. Many are fragments from comets or asteroids, whereas others are collision impact debris ejected from bodies such as the Moon or Mars.
Meteoroid embedded in aerogel; the meteoroid is 10 µm in diameter and its track is 1.5 mm long
2008 TC3 meteorite fragments found on February 28, 2009, in the Nubian Desert, Sudan
Meteor seen from the site of the Atacama Large Millimeter Array (ALMA)
A meteor of the Leonid meteor shower; the photograph shows the meteor, afterglow, and wake as distinct components