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perihelion

American  
[per-uh-hee-lee-uhn, -heel-yuhn] / ˌpɛr əˈhi li ən, -ˈhil jən /

noun

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


perihelion British  
/ ˌpɛrɪˈhiːlɪən /

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

perihelion Scientific  
/ pĕr′ə-hēlē-ən /
  1. The point at which an orbiting object, such as a planet or a comet, is closest to the Sun.

  2. Compare aphelion perigee


Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of perihelion

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

Compare meaning

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The images were taken about a month after the comet's closest approach to the Sun, known as perihelion.

From Science Daily Mar. 21, 2026

On Monday, the comet was at perihelion, the point at which it is closest to the Sun, which influences how bright it appears.

From BBC Jan. 13, 2025

The last perihelion, if you’re wondering, was on January 4, 2023, and Earth’s center was 147,098,924 km from that of the sun, or about 1.5 percent closer than average.

From Scientific American Jun. 30, 2023

Even as the Northern Hemisphere experiences winter’s chill, our planet on Wednesday will be at perihelion, the closest it gets to the sun during its elliptical orbit.

From New York Times Jan. 1, 2023

In the six weeks in which Mercury moves from aphelion to perihelion, it approaches the Sun by fourteen millions of miles, and the heat received by it is increased 2½ times.

From Are the Planets Inhabited? by E. Walter (Edward Walter) Maunder

The extremes of temperature at perihelia and aphelia to which comets are subjected did not bother him particularly.

From Astronomy: The Science of the Heavenly Bodies by David Peck Todd

The art has also been applied to the observation of comets at distances from their perihelia so great as to prevent their visual observation.

From History of Astronomy by George Forbes

This comet, therefore, which, according to Goldschmidt, passes beyond the orbit of Jupiter, is one of the few whose perihelia are beyond Mars.

From COSMOS: A Sketch of the Physical Description of the Universe, Vol. 1 by Alexander von Humboldt

In recent years a few have been discovered which are at times considerably within the orbit of Mars, the nearest perihelia being less than 15 million miles beyond the earth's orbit.

From The New Gresham Encyclopedia. Vol. 1 Part 2 Amiel to Atrauli by Various

Those—and they are many—who vaguely think that science is something different from common-sense, and that any book is scientific which talks about perihelia and asymptotes and cetacea, will find their vague notions here well corroborated.

From The Unseen World and Other Essays by John Fiske

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