perihelion

views updated Jun 27 2018

per·i·he·li·on / ˌperəˈhēlyən; -ˈhēlēən/ • n. (pl. -he·li·a / -ˈhēlyə; -ˈhēlēə/ or -he·li·ons) Astron. the point in the orbit of a planet, asteroid, or comet at which it is closest to the sun.The opposite of aphelion.

perihelion

views updated May 08 2018

perihelion The point in the Earth's elliptical orbit at which the planet is closest to the Sun. During the present epoch this occurs about the beginning of January, when the average amount of incident solar radiation is at a maximum. See also APHELION.

perihelion

views updated May 21 2018

perihelion Point in the orbit of a planet, asteroid, comet or other body (such as a spacecraft) moving around the Sun at which the body is nearest the Sun.

perihelion

views updated May 17 2018

perihelion XVII. Graecized form of modL. perihēlium, f. Gr. PERI- + hélios SUN.