| 释义 |
‖ perihelion Astr.|pɛrɪˈhiːlɪən|
Also 7–8 -ium. Pl. -ia.
[A Græcized form of mod.L. perihēlium (f. Gr. περί close about + ἥλιος sun), the latter introduced by Kepler on the analogy of perigēum, περίγειον (see Prodr. Dissert. Cosmographicarum, 1596, and Epitome Astronom. Copernic. 1618). Cf. F. périhélie (1740 in Hatz.-Darm.).]
1. That point in the orbit of a planet, comet, or other heavenly body, at which it is nearest to the sun. Opp. to aphelion.
1666Phil. Trans. I. 240 Not at present in the Perihelium of its Orbe, but nearer its Aphelium. 1690Leybourn Curs. Math. 768 The Aphelium is P, and the Perihelium X. Ibid. 773 In Figure XXXV..a is the Aphelion, p the Perihelion. 1698J. Keill Exam. The. Earth (1734) 319 Comets..after their return from the Regions beyond Saturn, before they arrive at their Perihelia again. 1714Derham Astro-Theol. viii. iv. (1726) 237 The Comet in 1680, in its Perihelion, was above 166 times nearer the Sun than the Earth is. 1715tr. Gregory's Astron. I. 147 In its ascent from the Sun, from the Perihelium to the Aphelium. 1834M. Somerville Connex. Phys. Sc. xii. (1835) 108 The return of comets to their perihelia. Ibid. xxxv. 374 When the comets are in perihelio. 1880A. R. Wallace Isl. Life viii. 138 During the period we are now discussing..the south polar area, having its winter in perihelion, would have had less ice.
attrib.1676Halley in Rigaud Corr. Sci. Men (1841) I. 239 The perihelion distance [of a planet]. 1867–77G. F. Chambers Astron. iv. ii. 292, Dec. 9, 1838, was the epoch of the next perihelion passage. 1881Proctor Poetry Astron. xi. 397 Clouds of meteoric matter..making their perihelion swoop around the sun.
2. fig. Highest point, ‘zenith’.
1804W. Taylor in Ann. Rev. II. 232 Mr. Pitt was now in the perihelion of his popularity. 1873H. Spencer Stud. Sociol. ix. 239 From the perihelion of patriotism he is carried to the aphelion of anti-patriotism.
Hence periˈhelial, periˈhelian adjs., of or belonging to perihelion. (Now rare or Obs.)
1690Leybourn Curs. Math. 772 As is the Aphelian Distance of the Planet to the Perihelian Distance. 1738Machin in Phil. Trans. XL. 220 The Perihelian Distance..is many times less than the Semi-distance of the Foci. 1784Phil. Trans. LXXV. 144 To find the position of the axis and the perihelial distance. |