[ uh-pas-truhn, -tron ]

noun,plural ap·as·tra [uh-pas-truh]. /əˈpæs trə/. Astronomy.
  1. the point at which the stars of a binary system are farthest apart (opposed to periastron).

Origin of apastron

<New Latin <Greek ap-ap-2 + ástron star, constellation; on the model of apogee

Words Nearby apastron

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use apastron in a sentence

  • They wouldn't live to be crushed by disappointment when the Sky Fire receded as Beta went into the long swing toward apastron.

    Oomphel in the Sky | Henry Beam Piper

Scientific definitions for apastron


[ ə-păstrən ]

  1. The point at which an object, such as a planet or comet, is farthest from the center of mass of the star it is orbiting. Compare periastron.

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