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

But on other worlds, it’s more typical to find metamorphic rocks forged in the split-second shock of a meteoroid impact.

From National Geographic • Oct. 12, 2023

The meteoroid appeared so enormous they are sure they heard it roaring across the heavens.

From Los Angeles Times • Oct. 6, 2023

During that brief time, the meteoroid might travel dozens of kilometers horizontally through Earth’s atmosphere while also plummeting 10 or more kilometers.

From Scientific American • Sep. 8, 2023

One temblor was caused by a marsquake — an earthquake on Mars, that is — while the other came from a large meteoroid impact.

From Salon • Apr. 25, 2023

We wandered over to the first area—Space Is Dangerous—and watched a video of a hole being blown through a thick metal plate by a simulated meteoroid.

From "Sir Fig Newton and the Science of Persistence" by Sonja Thomas