planetary nebula

IPA/plˈanɪtəɹi nˈɛbjʊlə/
IPA/plˈænɪtˌɛɹi nˈɛbjʊlə/

planetary nebula — noun

1. a large, bright cloud of gas in space that forms when a dying star pushes its ou

1.名詞B2
釋義

a large, bright cloud of gas in space that forms when a dying star pushes its outer layers outward, leaving an extremely hot center that makes the gas shine

例句

The Hubble telescope took a beautiful picture of a planetary nebula shaped like a giant eye.

collocation: take a picture of [planetary nebula]

Astronomers in Tokyo discovered a new planetary nebula in the northern sky last week.

collocation: discover a planetary nebula

文法句型

a planetary nebula

planetary nebulae

用法筆記

Despite the name, a planetary nebula has nothing to do with planets. The term was chosen because these objects look round and greenish through a telescope, similar to how early astronomers saw the planet Uranus.

常見錯誤

A planetary nebula is a planet that exploded.
A planetary nebula is a glowing cloud of gas from a dying star, not a real planet.
💡The name is historical; these objects are not related to planets at all.