Earth & SkyGreek → English
Exoplanet
/ˈɛksoʊˌplænɪt/noun
A planet orbiting a star other than the Sun.
The Greek roots
ἔξω
éxō
outside, beyond
πλανήτης
planḗtēs
wanderer
Literally: “wanderer outside”
The story of the word
The word came into use in the 1990s because the objects did: 51 Pegasi b, found by Michel Mayor and Didier Queloz in 1995, was the first planet confirmed around an ordinary star like ours. Outside means outside the solar system. The second half still carries the old Greek complaint that these lights refuse to hold their place among the fixed stars.
- How it travelled
- Ancient Greek → scientific coinage → English
- First recorded
- 1990s
Same family
planetexosphereexodusexoskeleton
In a sentence
Most known exoplanets were found by watching a star dim as something crossed it.