celestial sphere

celestial sphere
An imaginary sphere of infinite radius, centered at the center of the earth, on which the apparent motion of celestial bodies takes place. Because all stars are so far from an earthbound observer that they can be located solely by their direction, it is convenient to presume they are located on the inside of a spherical surface centered on the observer. Because the radius of earth is negligible, it is convenient to consider earth, rather than the terrestrial observer, centered in the celestial sphere. Stars are designated by their location on this sphere, and planets and other heavenly bodies are located against this background.

Aviation dictionary. 2014.

Look at other dictionaries:

  • Celestial sphere — [ celestial equator.] In astronomy and navigation, the celestial sphere is an imaginary rotating sphere of gigantic radius , concentric and coaxial with the Earth. All objects in the sky can be thought of as lying upon the sphere. Projected from… …   Wikipedia

  • celestial sphere — n. an imaginary sphere of infinite extent on which all celestial objects appear to lie: the observer is always at its center …   English World dictionary

  • celestial sphere — dangaus sfera statusas T sritis fizika atitikmenys: angl. celestial sphere vok. Himmelskugel, f; Himmelssphäre, f rus. небесная сфера, f; небосвод, m pranc. sphère céleste, f …   Fizikos terminų žodynas

  • celestial sphere — dangaus sfera statusas T sritis Gynyba apibrėžtis Įsivaizduojama neriboto spindulio sfera, koncentriška su Žemės rutuliu, į kurią projektuojami visi dangaus kūnai, išskyrus Žemę. atitikmenys: angl. celestial sphere pranc. sphère céleste …   NATO terminų aiškinamasis žodynas

  • celestial sphere — the imaginary spherical shell formed by the sky, usually represented as an infinite sphere, the center of which is a given observer s position. [1875 80] * * * Apparent surface of the heavens, on which the stars seem to be fixed. For the purpose… …   Universalium

  • celestial sphere — noun the apparent surface of the imaginary sphere on which celestial bodies appear to be projected • Syn: ↑sphere, ↑empyrean, ↑firmament, ↑heavens, ↑vault of heaven, ↑welkin • Derivationally related forms: ↑firmamental …   Useful english dictionary

  • celestial sphere — An imaginary sphere of infinite radius concentric with the Earth, on which all celestial bodies except the Earth are imagined to be projected …   Military dictionary

  • celestial sphere — noun Date: 1829 an imaginary sphere of infinite radius against which the celestial bodies appear to be projected and of which the apparent dome of the visible sky forms half …   New Collegiate Dictionary

  • celestial sphere — noun An abstract sphere of infinite radius which serves as the imaginary backdrop for celestial objects, and of which the visible sky is one hemisphere. Syn: empyrean, firmament …   Wiktionary

  • celestial sphere — noun an imaginary sphere of which the observer is the centre and on which all celestial objects are considered to lie …   English new terms dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”