celestial+sphere
111International Celestial Reference System — L ICRS, pour International Celestial Reference System (système de référence céleste international), est un ensemble de conventions adoptées par l Union astronomique internationale pour normaliser le système de coordonnées équatoriales. Il défini… …
112armillary sphere — noun a celestial globe consisting of metal hoops; used by early astronomers to determine the positions of stars • Syn: ↑armilla • Hypernyms: ↑celestial globe …
113oblique sphere — noun The celestial or terrestrial sphere when its axis is oblique to the horizon of the place; or as it appears to an observer at any point on the earth except the poles and the equator …
114armillary sphere — noun An instrument consisting of graduated metal circles used to represent the motions of celestial bodies around the earth …
115celestialglobe — celestial globe n. A model of the celestial sphere showing the positions of the stars and other celestial bodies. * * * …
116celestialequator — celestial equator n. A great circle on the celestial sphere in the same plane as the earth s equator. Also called equinoctial, equinoctial circle. * * * …
117celestialhorizon — celestial horizon n. A great circle on the celestial sphere having a plane that passes through the center of the earth and is parallel to an observer s horizon. Also called rational horizon. * * * …
118celestialpole — celestial pole n. Either of two diametrically opposite points at which the extensions of the earth s axis intersect the celestial sphere. * * * …
119celestialsphere — celestial sphere Jerry Malone n. An imaginary sphere of infinite extent with the earth at its center on which the stars, planets, and other heavenly bodies appear to be located. * * * …
120Sundial — A sundial is a device that measures time by the position of the Sun. In common designs such as the horizontal sundial, the sun casts a shadow from its style (a thin rod or a sharp, straight edge) onto a flat surface marked with lines indicating… …