perihelion

Definitions of perihelion
  1. noun
    periapsis in solar orbit; the point in the orbit of a planet or comet where it is nearest to the sun
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    Antonyms:
    aphelion
    apoapsis in solar orbit; the point in the orbit of a planet or comet that is at the greatest distance from the sun
    type of:
    periapsis, point of periapsis
    (astronomy) the point in an orbit closest to the body being orbited
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