perihelion

[ per-uh-hee-lee-uhn, -heel-yuhn ]

noun

, Astronomy.

, plural per·i·he·li·a [per-, uh, -, hee, -lee-, uh, -, heel, -y, uh].

1. the point in the orbit of a planet or comet at which it is nearest to the sun.

perihelion

/ ˌpɛrɪˈhiːlɪən /

noun

1. See aphelion
   the point in its orbit when a planet or comet is nearest the sun Compare aphelion

perihelion

/ pĕr′ə-hē′lē-ən /

1. The point at which an orbiting object, such as a planet or a comet, is closest to the Sun.
2. Compare aphelion

Other Words From

• peri·heli·al peri·heli·an adjective

Word History and Origins

Origin of perihelion¹

1660–70; < Greek peri- peri- + hḗli ( os ) sun + -on neuter noun suffix, on the model of perigee; earlier in the New Latin form perihelium

Word History and Origins

Origin of perihelion¹

C17: from New Latin perihēlium, from peri- + Greek hēlios sun

Example Sentences

The point where a planet’s orbit comes closest to the sun is its perihelion.

From Science News For Students

I'm not trying to calculate the perihelion of Jupiter or do 3D renderings of the National Cathedral.

From The Daily Beast

The direction of the axis major of the orbit, which was found by calculating the longitude of the comet's perihelion.

From Project Gutenberg

The comet returned at the appointed time; and on the 12th of March, 1759, reached its perihelion.

From Project Gutenberg

At its perihelion it travels thousands of leagues per minute; at its aphelion it does not pass over more than a few yards.

From Project Gutenberg

The only sensible effect will be a secular motion of the perihelion.

From Project Gutenberg

The motion of Mercury's perihelion would therefore be 7´´ in the theory of Lorentz and 5´´.6 in that of Abraham.

From Project Gutenberg