apastron

[uh-pas-truhn, -tron]

noun

Astronomy.

plural

apastra 

1. the point at which the stars of a binary system are farthest apart (periastron ).

apastron

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.

2. Compare periastron

Word History and Origins

Origin of apastron¹

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

Example Sentences

These orbs complete a revolution in 180 years, and when in apastron are seventeen times more remote from each other than when at periastron.

From Project Gutenberg

The pair travel in an orbit from fourteen to forty-two times the radius of the Earth’s orbit; so that when at apastron they are three times as distant from each other as when at periastron.

From Project Gutenberg

The eccentricity of their orbit approaches in form that of Faye’s comet, which travels round the Sun; consequently the stars, when at apastron, are twice their periastron distance.

From Project Gutenberg

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

From Project Gutenberg