aphelion

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a·phe·li·on / əˈfēlyən; əˈfēlēən/ • n. (pl. a·phe·li·a / əfēlyə; əˈfēlēə/ or a·phe·li·ons) Astron. the point in the orbit of a planet, asteroid, or comet at which it is furthest from the sun: Mars is at aphelion. The opposite of perihelion.

aphelion

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aphelion (astron.) point of a planet's or comet's orbit at which it is farthest from the sun. XVII. Graecized form (Kepler) of modL. aphēlium, f. APO- + Gr. hélios SUN, after L. apogæum APOGEE.

aphelion

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aphelion Point in the Earth's elliptical orbit at which the planet is farthest from the Sun. See also PERIHELION.