periastron

[ per-ee-as-truhn, -tron ]

noun,plural per·i·as·tra

[per-ee-as-truh]. /ˌpɛr iˈæs trə/. Astronomy.

the point at which the stars of a binary system are closest (opposed to apastron).

Origin of periastron

1850–55; <peri- + Greek ástron star; modeled on perihelion

Other words from periastron

per·i·as·tral, adjective

Words Nearby periastron

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use periastron in a sentence

At least, the periastron effects; there was another angle to it.
Oomphel in the Sky | Henry Beam Piper

British Dictionary definitions for periastron

periastron

/ (ˌpɛrɪˈæstrɒn) /

noun

astronomy the point in the orbit of a body around a star when it is nearest to the star, esp applied to double-star systems

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

Scientific definitions for periastron

periastron

[ pĕr′ē-ăs′trən, -trŏn ]

Plural periastra

The point at which an object, such as a planet or comet, is closest to the center of mass of the star it is orbiting. Compare apastron.

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