English Dictionary

asteroid

/ˈæstəɹɔɪd/

noun

(astronomy) A naturally occurring solid object, which is smaller than a planet and is not a comet, that orbits a star and often has an irregular shape.

Scientists are studying the trajectory of an asteroid that is approaching Earth.

意味（1）

(astronomy) A naturally occurring solid object, which is smaller than a planet and is not a comet, that orbits a star and often has an irregular shape.

意味（2）

(astronomy) In the Solar system, such a body that orbits within the orbit of Jupiter

The orbital planes of asteroids, minor bodies that circle the Sun mainly between the orbits of Mars and Jupiter, are often more tilted ...