Rigel(redirected from Algebar)
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Rigel(rī`jəl), bright star in the constellation OrionOrion,
in astronomy, constellation located on the celestial equator. It is one of the most conspicuous and easily recognizable constellations in the entire sky. From ancient times it has been mentioned in the literature of many peoples and is traditionally depicted as the figure
..... Click the link for more information. ; Bayer designation Beta Orionis; 1992 position R.A. 5h14.2m, Dec. −8°13'. A huge, blue supergiant of spectral classspectral class,
in astronomy, a classification of the stars by their spectrum and luminosity. In 1885, E. C. Pickering began the first extensive attempt to classify the stars spectroscopically.
..... Click the link for more information. B8 Ia, Rigel has an intrinsic brightness about 40,000 times as luminous as that of the sun. It is an irregular variable starvariable star,
star that varies, either periodically or irregularly, in the intensity of the light it emits. Other physical changes are usually correlated with the fluctuations in brightness, such as pulsations in size, ejection of matter, and changes in spectral type, color, or
..... Click the link for more information. , with apparent magnitudemagnitude,
in astronomy, measure of the brightness of a star or other celestial object. The stars cataloged by Ptolemy (2d cent. A.D.), all visible with the unaided eye, were ranked on a brightness scale such that the brightest stars were of 1st magnitude and the dimmest stars
..... Click the link for more information. ranging from 0.08 to 0.20, making it normally the seventh-brightest star in the sky. Its distance from the earth is nearly 1,000 light-years. Rigel is actually a four-star system consisting of a visual binary starbinary star
or binary system,
pair of stars that are held together by their mutual gravitational attraction and revolve about their common center of mass. In 1650 Riccioli made the first binary system discovery, that of the middle star in the Big Dipper's handle, Zeta
..... Click the link for more information. , each component of which is itself a spectroscopic binary. Its name is from the Arabic word meaning "foot," indicating its position in the constellation.
Rigel(rÿ -jĕl) (β Ori) A massive luminous and remote bluish-white supergiant that is very conspicuous and is the brightest star in the constellation Orion. It marks Orion's left foot. According to the Hipparcos catalog, its distance from the Sun is about 773 light-years (237 parsecs), though estimates have ranged between 900 and 1400 l.y. If the Hipparcos measurement is correct, Rigel is at least 40 000 times as luminous as the Sun. Rigel's diameter is thought to equal 70 solar diameters. It is a member of a large association that includes the stars of Orion's Belt and the Orion nebula. There is a 7th-magnitude companion at a separation of 9″.5, which is itself a binary. mv : 0.18 (var.); Mv : –6.69(?); spectral type: B8 Iae.
(also β Orionis), a star of visual stellar magnitude 0.1, one of the brightest stars in the sky; the brightest star in the constellation of Orion. Rigel is located at a great distance from the sun (330 parsecs) and has a high luminosity—81,000 times greater than the luminosity of the sun. Rigel is a visual binary star; its companion star, of stellar magnitude 7, is separated from Rigel by 10ʺ.