| 释义 |
periaster, periastron Astron.|pɛrɪˈæstə(r), -ˈæstrən|
Also periastre.
[mod. f. Gr. περί close around + ἄστρον star, after perihelion, perigee.]
That point in the orbit of a heavenly body revolving around a star (as a companion star in a binary system, a comet, etc.) at which it is nearest to the star. Also attrib. Hence periˈastral a., of or pertaining to the periastron.
1851Nichol Archit. Heav. 223 The swiftness with which certain individuals of the Double Stars sweep past their perihelia,—or rather their periasters—is amazing. 1867–77G. F. Chambers Astron. Vocab. 918 Periastre. 1872Proctor Ess. Astron. iii. 40 Twenty millions of years..must have elapsed since those comets were last in periastral passage. 1876Athenæum 16 Dec. 805/2 The small star is now at or near its periastron. 1887Lockyer in Proc. R. Soc. XLIII. 154 In some [variable stars]..the variation would seem to be partly due to swarms of meteorites moving around a bright or dark body, the maximum light occurring at periastron. 1890J. Thornton Adv. Physiog. xiv. §225. |