Translation guide
An asteroid is a small rocky body orbiting the sun. In Japanese, the standard term is 小惑星 (shōwakusei). In casual or sci-fi contexts, アステロイド (asuteroido) is also used.
Referring to a rocky object in space, smaller than a planet, orbiting the sun.
Standard scientific and general term for asteroid.
小惑星が地球に接近している。
An asteroid is approaching Earth.
この小惑星は直径約500メートルだ。
This asteroid is about 500 meters in diameter.
Literally 'stardust', sometimes used poetically for small celestial bodies like asteroids or meteoroids. Not a scientific term.
小惑星 is the formal, scientific term used in news and textbooks. アステロイド is a loanword often heard in pop culture, games, and casual talk. Use 小惑星 in most contexts.
Loanword from English, used in casual conversation, games, or sci-fi. Less formal than 小惑星.
アステロイドを破壊するゲームが好きだ。
I like games where you destroy asteroids.
宇宙には無数の星くずが漂っている。
Countless asteroids drift in space.