periastron

[ per-ee-as-truh n, -tron ]
/ ˌpɛr iˈæs trən, -trɒn /

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

periarteritis, periarteritis nodosa, periarthritis, periarticular, periarticular abscess, periastron, periaxillary, periblem, peribonca, peribronchial, peribronchiolar

Example sentences from the Web for 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
/ (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

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.