asteroid belt

American  

[as-tuh-roid belt] / ˈæs təˌrɔɪd ˌbɛlt /

noun

Astronomy.

1. the region in space between the orbits of Mars and Jupiter, containing the greatest population of asteroids in our solar system: comprising about half the mass of the asteroid belt are its four largest asteroids, namely, Ceres, Pallas, Vesta, and Hygieia.

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asteroid belt Cultural  

1. A region of the solar system between the orbits of the planets Mars and Jupiter. Most asteroids are found in the asteroid belt.

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Etymology

Origin of asteroid belt

First recorded in 1865–70

Example Sentences

On April 20, 2025, Lucy passed within 650 miles of Donaldjohanson while traveling through the main asteroid belt on its way to a group of Jupiter Trojan asteroids.

From Science Daily • Jun. 25, 2026

Donaldjohanson has remained in the asteroid belt since its formation, while Bennu and Ryugu eventually migrated into near-Earth orbits that periodically bring them close to our planet.

From Science Daily • Jun. 25, 2026

NASA’s Amit Kshatriya, the man behind Artemis, on the race with China to reach Mars, the asteroid belt and Jupiter’s moons.

From The Wall Street Journal • May 15, 2026

Its surface would lie even further from the asteroid belt, meaning all of us including planet Mars would be in the belly of the red beast.

From Space Scoop • Aug. 20, 2025

The rings of Saturn bear some resemblance to the asteroid belt: trillions of tiny icy moonlets orbiting the planet.

From "Cosmos" by Carl Sagan