perihelion

noun

peri·​he·​lion ˌper-ə-ˈhēl-yən 

plural perihelia ˌper-ə-ˈhēl-yə 

: the point nearest to the sun in the path of an orbiting celestial body (such as a planet) compare aphelion

perihelial

ˌper-ə-ˈhēl-yəl 

adjective

Examples of perihelion in a Sentence

Recent Examples on the Web

Key Facts Parker launched on Aug. 12, 2018, and has since conducted 23 perihelions — close passes — of the sun, getting to within 3.86 million miles (6.1 million kilometers) twice before today’s repeat performnce. —Jamie Carter, Forbes.com, 19 June 2025

After the comet reaches perihelion, it will only be seen from the Southern Hemisphere. —Skyler Caruso, People.com, 8 Apr. 2025

Meanwhile, its perihelion—the closest point on its orbit to the Sun—is 44.5 times that of the Earth's orbit, similar to Pluto's orbit. —Alyce Collins, MSNBC Newsweek, 26 May 2025

When Earth is closest to the sun (called perihelion), its orbital rate is faster than average, so the true sun lags behind the mean sun. —Phil Plait, Scientific American, 5 June 2025

Word History

Etymology

New Latin, from peri- + Greek hēlios sun — more at solar

First Known Use

1666, in the meaning defined above

Rhymes for perihelion

• abelian
• carnelian
• hegelian
• karelian
• aristotelian
• elian

Kids Definition

perihelion

noun

peri·​he·​lion ˌper-ə-ˈhēl-yən 

: the point in the path of a heavenly body (as a planet) that is nearest to the sun