meteoroid

American  

[mee-tee-uh-roid] / ˈmi ti əˌrɔɪd /

noun

Astronomy.

1. any of the small bodies, often remnants of comets, traveling through space: when such a body enters the earth's atmosphere it is heated to luminosity and becomes a meteor.

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meteoroid British  

/ ˈmiːtɪəˌrɔɪd /

noun

1. any of the small celestial bodies that are thought to orbit the sun, possibly as the remains of comets. When they enter the earth's atmosphere, they become visible as meteors

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meteoroid Scientific  

/ mē′tē-ə-roid′ /

1. A small, rocky or metallic body revolving in interplanetary space around the Sun. A meteoroid is significantly smaller than an asteroid, ranging from small grains or particles to the size of large boulders. The clustered meteoroids associated with regular annual meteor showers are believed to be very small particles of cometary debris. Meteoroids that survive their passage through the Earth's atmosphere and land as meteorites are somewhat larger, solitary bodies and are encountered in no predictable pattern.

2. See Note at meteor

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Other Word Forms

• meteoroidal
  adjective

Etymology

Origin of meteoroid

First recorded in 1860–65; meteor + -oid

Explanation

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.

Example Sentences

The comet will look like a bright fireball with a long, extended tail, said Bill Cooke, lead of NASA’s Meteoroid Environment Office at the Marshall Space Flight Center in Alabama, KABC-TV reported.

From Los Angeles Times • Oct. 11, 2024

“This is going to be an all or nothing event,” wrote Bill Cooke, who leads NASA’s Meteoroid Environment Office at NASA’s Marshall Space Flight Center, in a blog post on the shower.

From Seattle Times • May 27, 2022

NASA’s Meteoroid Environment Office detected 33 fireballs over the eastern two-thirds of the Lower 48 Monday night.

From Washington Post • Dec. 11, 2018