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Hadar, in astronomy

(Encyclopedia)Hadar or Beta Centauri bāˈtə sĕntôrˈē [key], bright star in the constellation Centaurus; 1992 position R.A. 14h01.7m, dec. −60°13′. A bluish-white giant of spectral class B1 II, it has an ...

Castor, in astronomy

(Encyclopedia)Castor kăsˈtər [key], bright star in the constellation Gemini; Bayer designation α Geminorum; 1992 position R.A. 7h34.1m, Dec. +31°54′. Slightly dimmer than Pollux, with which it forms the Twin...

corona, in astronomy

(Encyclopedia)corona, luminous envelope surrounding the sun, outside the chromosphere. Its density is less than one billionth that of the earth's atmosphere. The corona is visible only at the time of totality durin...

gamma-ray astronomy

(Encyclopedia)gamma-ray astronomy, study of astronomical objects by analysis of the most energetic electromagnetic radiation they emit. Gamma rays are shorter in wavelength and hence more energetic than X rays (see...

ultraviolet astronomy

(Encyclopedia)ultraviolet astronomy, study of celestial objects by means of the ultraviolet radiation they emit, in the wavelength range from about 90 to about 350 nanometers. Ultraviolet (UV) line spectrum measure...

Megaclite

(Encyclopedia)Megaclite, in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. ...

Taygete

(Encyclopedia)Taygete, in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. ...

Themisto

(Encyclopedia)Themisto, in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. ...

Chaldene

(Encyclopedia)Chaldene, in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. ...

Erinome

(Encyclopedia)Erinome, in astronomy, one of the 39 known moons, or natural satellites, of Jupiter. ...