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Sirius |
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Sirius (sĭr`ēəs), or Dog Star, brightest star in the sky. It is located in the constellation Canis Major Canis Major [Lat.,=greater dog], constellation lying near the celestial equator, SE of Orion. Known as the Large Dog (Canis Minor is the Small Dog), it was associated with the figure of a dog by many cultures; the ancient Greeks identified it as one of Orion's ..... Click the link for more information. (1992 position R.A. 6h44.8m, Dec. −16°42'); its Bayer designation is Alpha Canis Majoris. Sirius [Gr.,=scorching], having an apparent magnitude magnitude, 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 ..... Click the link for more information. of −1.45, is exceeded in brightness only by the sun, the moon, and Venus and by Mars and Jupiter at their maximum brightness. A white, main-sequence star of spectral class spectral 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. A1 V, Sirius is about twice the size of the sun and about 20 times as luminous. It is also one of the nearest stars, lying at a distance of 8.7 light-years, so that it has been studied extensively. From an analysis of its motions, F. W. Bessel concluded (1844) that it had an unseen companion, which was later (1862) confirmed by observation. The companion, Sirius B, is a white-dwarf star and has also been the object of considerable study because it is the first white dwarf whose spectrum was found to exhibit a gravitational red shift red shift or redshift, in astronomy, the systematic displacement of individual lines in the spectrum of a celestial object toward the red, or longer wavelength, end of the visible spectrum. The effect was discovered by V. M. ..... Click the link for more information. as predicted by the general theory of relativity relativity, physical theory, introduced by Albert Einstein, that discards the concept of absolute motion and instead treats only relative motion between two systems or frames of reference. ..... Click the link for more information. . Siriusor Dog StarBrightest star in the night sky (apparent magnitude −1.44), a binary star about 8.6 light-years from the Sun in the constellation Canis Major. The bright component of the binary is a blue-white star 23 times as luminous as the Sun, about twice the size, and considerably hotter; its companion was the first white dwarf star discovered. Its name probably comes from a Greek word meaning “sparkling” or “scorching.” The ancient Egyptians used its predawn rising to predict the annual flooding of the Nile. The ancient Romans associated the rising of the Dog Star at dawn with the hottest part of the year, called the “dog days.” Sirius [′sir·ē·əs] (astronomy) The brightest-appearing star in the sky; 8.7 light-years from the sun, spectral class A1V; it has a white dwarf companion. Also known as Dog Star. Sirius dog star; brightest star in the heavens. [Astronomy: EB, IX: 238] See : Brightness Sirius (α Canis Majoris), the brightest star in the heavens, with a visual stellar magnitude of — 1.46. Sirius has a luminosity 22 times greater than that of the sun; its distance from the sun is 2.7 parsecs. Sirius is a system of two stars: the satellite of Sirius, a star 10,000 times fainter than Sirius itself, was the first white dwarf to be discovered. Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content. |
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No references found | In July and August, a canicula, or dry spell, made it impossible to fertilize - and though September was fairly normal, in October Guatemala was hit by the tail end of Hurricane Pauline which slammed into Mexico's Pacific coast. As a weeklong heat wave lifted on Friday night, 1,000 people attended the Canicula Family Benefit Concert at the Simi Valley Drive-in, where four bands entertained beneath a crescent moon. Akai"), a subsidiary of the Company, have resolved to issue and allot to Canicula B. |
Canicula |
Cange, Charles du Fresne, Lord du Cango Cangrande I della Scala cangue CANH CANHC CANHE CANHIGEO CANHR Cani Cani Cani Cani Cani Caniapiscau Caniapiscau Caniapiscau, Quebec Caniapiscau, Quebec Canibal Canibal Canibal Canibalism Canibalism Canibalism Caniche Caniche Caniche canicola fever canicola fever Canicross Bikejoering Verband Austria Canicula canicularcanicular days Canicular year canicule canid canid canid canid Canidae Canidae Canidae Canids Canids Canids CANIECE CANIF Caniff, Milt Caniformia CANII Canik canikin Caninae Caninae Caninae Caninal canine canine canine canine Canine & Detection Research Institute | |||||||
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