periastron

periastron [per-ee-as-truh n, -tron] ExamplesWord Origin noun, plural per·i·as·tra [per-ee-as-truh] /ˌpɛr iˈæs trə/. Astronomy.

1. 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 Related formsper·i·as·tral, adjective Examples from the Web for periastron Historical Examples of periastron

At least, the periastron effects; there was another angle to it.

Oomphel in the Sky

Henry Beam Piper

British Dictionary definitions for periastron periastron noun

1. 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

periastron in Science periastron [pĕr′ē-ăs′trən, -trŏn] Plural periastra

1. 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.