perihelion

IPA/ˌper.ɪˈhiː.li.ən/
IPA/ˌper.ɪˈhiː.li.ən/

perihelion — noun

  • perihelionsingular
  • periheliaplural

1. the place on a solar orbit where a planet, comet, or spacecraft is at its shorte

1.名詞C2
釋義

the place on a solar orbit where a planet, comet, or spacecraft is at its shortest distance from the Sun

例句

Earth reaches perihelion in early January each year.

reach perihelion in + time period

The comet moved fastest when it passed perihelion near the Sun.

pass perihelion

同義詞
  • periapsis

    the broader scientific term for the nearest point in any orbit, not only one around the Sun

  • closest approach to the Sun

    a descriptive phrase rather than the technical astronomy term

反義詞
  • aphelion

    the point where the same orbiting body is farthest from the Sun

文法句型

at perihelion

reach perihelion

pass perihelion

用法筆記

Used in astronomy for an orbit around the Sun. For an orbit around another body, scientists usually use periapsis or a more specific term instead.

常見錯誤

❌The satellite reached perihelion around Jupiter.
✅The satellite reached periapsis around Jupiter.
💡perihelion is only for an orbit around the Sun, not around another planet.