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ether, in physics and astronomy

(Encyclopedia)ether or aether, in physics and astronomy, a hypothetical medium for transmitting light and heat (radiation), filling all unoccupied space; it is also called luminiferous ether. In Newtonian physics a...

Aquila, in astronomy

(Encyclopedia)Aquila [Lat.,=the eagle], equatorial constellation located N of Sagittarius and Capricornus, lying partly in the Milky Way. It is sometimes depicted as an eagle. It contains the bright star Altair (Al...

radio astronomy

(Encyclopedia)radio astronomy, study of celestial bodies by means of the electromagnetic radio frequency waves they emit and absorb naturally. Radio waves also come from outside the Milky Way. These extragalact...

Leo, in astronomy

(Encyclopedia)Leo [Lat.,=the lion], northern constellation lying S of Ursa Major and on the ecliptic (apparent path of the sun through the heavens) between Cancer and Virgo; it is one of the constellations of the z...

sun, in astronomy

(Encyclopedia)CE5 Structure of the sun sun, intensely hot, self-luminous body of gases at the center of the solar system. Its gravitational attraction maintains the planets, comets, and other bodies of the sola...

Draco, in astronomy

(Encyclopedia)Draco [Lat.,=the dragon], northern constellation lying SE of Ursa Minor and N of Lyra and Hercules. It is traditionally depicted as a dragon. Draco contains the bright star Eltanin (Gamma Draconis). T...

Mimosa, in astronomy

(Encyclopedia)Mimosa or Beta Crucis bāˈtə kro͞oˈsĭs [key], bright star in the constellation Crux (Southern Cross); 1992 position R.A. 12h47.3m, Dec. −59°39′. It is sometimes called Becrux, from its Bayer...

Regulus, in astronomy

(Encyclopedia)Regulus rĕgˈyələs [key], brightest star in the constellation Leo; Bayer designation Alpha Leonis; 1992 position R.A. 10h08m, Dec. +12°00′. A bluish-white main-sequence star of spectral class B7...

Pollux, in astronomy

(Encyclopedia)Pollux, brightest star in the constellation Gemini; Bayer designation Beta Geminorum; 1992 position R.A. 7h44.8m, Dec. +28°03′. An orange giant of spectral class K0 III, it is the nearest giant sta...

Algol, in astronomy

(Encyclopedia)Algol ălˈgŏl [key], famous variable star in the constellation Perseus; Bayer designation β Persei; 1992 position R.A. 3h07.7m, Dec. +40°55′. Algol's variation in apparent magnitude, from 2.06 t...