Meteoroid

A meteoroid is a small rocky or metallic body in <a href="/facts/Outer_space/R3LRKyFs">outer space</a>.
Meteoroids are distinguished as objects significantly smaller than <a href="/facts/Asteroid/g7Ulr1VB">asteroids</a>, ranging in size from grains to objects up to 1 m (3 ft 3 in) wide. Objects smaller than meteoroids are classified as <a href="/facts/Micrometeoroids/VSkmQYv1">micrometeoroids</a> or <a href="/facts/Space_dust/Uy6hlL29">space dust</a>. Many are fragments from <a href="/facts/Comet/w34utQCd">comets</a> or asteroids, whereas others are <a href="/facts/Impact_event/fbWu9Q4p">collision impact</a> <a href="/facts/Space_debris/X7YSKlXl">debris</a> ejected from bodies such as the <a href="/facts/Moon/zKHqEMPb">Moon</a> or <a href="/facts/Mars/AQGtVvz0">Mars</a>.
The visible passage of a meteoroid, comet, or asteroid <a href="/facts/Atmospheric_entry/p7TMk9sa">entering Earth's atmosphere</a> is called a <a href="/facts/Meteor/gcoGYw6o">meteor</a>, 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 <a href="/facts/Meteor_shower/ff47hYJA">meteor shower</a>.
An estimated 25 million meteoroids, micrometeoroids and other <a href="/facts/Space_debris/X7YSKlXl">space debris</a> enter Earth's atmosphere each day, which results in an estimated 15,000 tonnes of that material entering the atmosphere each year.
A <a href="/facts/Meteorite/NsmHlBlX">meteorite</a> is the remains of a meteoroid that has survived the <a href="/facts/Ablation/tTSHH09G">ablation</a> of its surface material during its passage through the atmosphere as a meteor and has impacted the ground.

Meteoroid open-in-new

Meteoroid