perihelion

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perihelion

(Academy Artworks)

The point nearest the sun in the orbit of a planet or other celestial body.

[Alteration of New Latin perihēlium : PERI– + Greek hēlios, sun.]

The point in the eath's orbit when, at 147.5 million km, it is closest to the sun; on 3 or 4 January.

Point in the elliptical orbit of a comet about the Sun in which it passes closest to the Sun.

The noun has one meaning:

Meaning #1: periapsis in solar orbit; the point in the orbit of a planet or comet where it is nearest to the sun
  Antonym: aphelion (meaning #1)