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

Researchers also note that Ammonite has a particularly high perihelion of 66 au (Astronomical Unit), which, to put it into perspective, is equivalent to 66 times the average distance between Earth and the sun. —Rosie McCall, Discover Magazine, 21 July 2025

Although the overall view from Earth degrades as the object approaches perihelion, some telescopes will be less visually impaired. —Jonathan O'Callaghan, Scientific American, 16 July 2025

The difference isn't huge — the sun today appears to be a mere arcminute (1/60th of a degree) smaller than at its perihelion. —Jamie Carter, Forbes.com, 3 July 2025

Unfortunately, however, in October, when the object will be at its warmest, closest point to our star (called perihelion), Earth will be on the other side of the sun. —Jonathan O'Callaghan, Scientific American, 16 July 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