periastron

[ per-ee-as-truhn, -tron ]

noun

, Astronomy.

, plural per·i·as·tra [per-ee-, as, -tr, uh].

1. the point at which the stars of a binary system are closest ( apastron ).

periastron

/ ˌpɛrɪˈæstrɒn /

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

/ 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.
2. Compare apastron

Other Words From

• peri·astral adjective

Word History and Origins

Origin of periastron¹

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

Example Sentences

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

From Project Gutenberg