Dictionary.com

periastron

[ per-ee-as-truhn, -tron ]
/ ˌpɛr iˈæs trən, -trɒn /
Save This Word!

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).

QUIZZES

QUIZ YOURSELF ON THE 12 TYPES OF VERB TENSES!

Loosen up your grammar muscles because it’s time to test your knowledge on verb tenses!
Question 1 of 6
The verb tenses can be split into which 3 primary categories?

Meet Grammar Coach

Write or paste your essay, email, or story into Grammar Coach and get grammar helpImprove Your Writing

Meet Grammar Coach

Improve Your Writing
Write or paste your essay, email, or story into Grammar Coach and get grammar help

Origin of periastron

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

OTHER WORDS FROM periastron

per·i·as·tral, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

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-ăstrən, -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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
FEEDBACK