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Castor
Castor , bright star in the constellation Gemini ; Bayer designation α Geminorum; 1992 position R.A. 7 h 34.1 m , Dec. +31°54′. Slightly dimmer than Pollux , with which it forms the Twins, Castor has an apparent magnitude of 1.58, which still makes it one of the 25 brightest stars in the sky. Castor is actually a six-star system, being a visual triple each component of which is a binary star ; the three components are an eclipsing binary and a pair of spectroscopic binaries. The two brightest components are white, main-sequence stars of spectral classes A1 and A5. The system is about 50 light-years distant. |
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"Castor." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. "Castor." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1E1-Castor.html "Castor." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-Castor.html |
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Castor
Castor The star Alpha Geminorum, which appears to the naked eye of magnitude 1.6 but which is actually a complex multiple star. A small telescope divides Castor into two stars of magnitudes 1.9 and 2.9, both A-type dwarfs, which orbit each other with a period of about 450 years. Each is a spectroscopic binary. There is a third star, known as Castor C or YY Geminorum, an eclipsing pair of M1 dwarfs that ranges from magnitude 9.2 to 9.6 in a period of 0.8 days. The six-star system lies 52 l.y. away.
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"Castor." A Dictionary of Astronomy. 1997. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. "Castor." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1O80-Castor.html "Castor." A Dictionary of Astronomy. 1997. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-Castor.html |
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Castor
Cas·tor / ˈkastər/ 1. Greek Mythol. the twin brother of Pollux. See Dioscuri. 2. Astron. the second brightest star in the constellation Gemini, close to Pollux. It is a multiple star system, the three components visible in a moderate telescope being close binaries. |
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"Castor." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. "Castor." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1O999-castor.html "Castor." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-castor.html |
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castor
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T. F. HOAD. "castor." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "castor." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1O27-castor1.html T. F. HOAD. "castor." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-castor1.html |
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castor
castor 1 beaver, unctuous substance obtained from the beaver (used as a drug). XIV. — (O)F. or L. castor — Gr. kástōr. The history of the use of castor oil (XVIII) for the pale-yellow oil obtained from the seeds of the plant Ricinus communis is obscure.
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Cite this article
T. F. HOAD. "castor." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "castor." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1O27-castor.html T. F. HOAD. "castor." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-castor.html |
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castor
cas·tor / ˈkastər/ • n. a reddish-brown oily substance secreted by beavers, used in medicine and perfumes. |
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Cite this article
"castor." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. "castor." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1O999-castor010.html "castor." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-castor010.html |
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Castor
Castor Peterb. Cæstre 948, Castre 1086 (DB). ‘The Roman fort’. OE cæster.
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A. D. MILLS. "Castor." A Dictionary of British Place-Names. 2003. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. A. D. MILLS. "Castor." A Dictionary of British Place-Names. 2003. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1O40-Castor.html A. D. MILLS. "Castor." A Dictionary of British Place-Names. 2003. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O40-Castor.html |
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castor
castor see beaver . |
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Cite this article
"castor." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. "castor." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1E1-X-castor.html "castor." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-castor.html |
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castor
castor
•barter, Bata, cantata, carter, cassata, charter, chipolata, ciabatta, darter, desiderata, errata, garter, imprimatur, Inkatha, Jakarta, Magna Carta, Maratha, martyr, Odonata, passata, persona non grata, rata, Renata, Río de la Plata, serenata, sonata, Sparta, starter, strata, taramasalata, tartar, Tatar, Zapata
•after, drafter, grafter, hereafter, laughter, rafter, thereafter, whereafter
•chanter, enchanter, granter, planter, supplanter, transplanter, Vedanta
•blaster, caster, castor, faster, grandmaster, headmaster, master, pastor, plaster
•alabaster • telecaster • forecaster
•broadcaster • sportscaster
•newscaster • sandblaster
•bandmaster • taskmaster
•pastmaster • paymaster • ringmaster
•quizmaster • spymaster
•housemaster • Scoutmaster
•toastmaster • schoolmaster
•harbourmaster (US harbormaster)
•quartermaster • substrata
•sought-after
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"castor." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 25 May. 2012 <http://www.encyclopedia.com>. "castor." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 25, 2012). http://www.encyclopedia.com/doc/1O233-castor.html "castor." Oxford Dictionary of Rhymes. 2007. Retrieved May 25, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-castor.html |
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