perihelion

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perihelion

(Academy Artworks)

n., pl., -he·li·a (-hē'lē-ə, -hēl'yə).
The point nearest the sun in the orbit of a planet or other celestial body.

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

perihelial per'i·he'li·al (-hē'lē-əl, -hēl'yəl) adj.

(per-i-HEE-lee-uhn_, -HEEL-yun)

noun
The point in the orbit of a celestial body that is nearest to the sun.

Etymology
From Greek peri- (around, near) + helios (sun). The point farthest from the sun is called aphelion, from apo- (away)

Usage
"Come Jan. 3, Earth will reach perihelion, its closest approach to the sun at 91,399,727 miles." — Pete Zapadka; That Sun Feels Mighty Close During Summer. False!; Pittsburgh Post-Gazette; Jul 6, 2007.

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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.