A cada 27 anos, Epsilon Aurigae se esmaece, permanecendo com um brilho tênue durante cerca de dois anos, antes de seu brilho voltar a aumentar. Desde o século 19, astrônomos estudam a misteriosa estrela, finalmente provando que Epsilon Aur, centrada nesta visão telescópica do céu, estava, na verdade, sob um longo eclipse causado por um objeto escuro próximo. Mas a natureza do objeto e mesmo o estado da estrela em si não puderam ser medidos por observações. Continuando a colher evidências, o Citizen Sky, um grupo de astrônomos profissionais e amadores, está estudando o atual eclipse de Epsilon Aur, informando que iniciou-se em agosto de 2009 e no final de dezembro havia atingido seu ponto mais profundo. Epsilon Aur deverá agora permanecer com brilho fraco durante todo o ano de 2010, antes de, rapidamente, retomar seu brilho normal, em 2011. Nesse interim, dados em infravermelho do Telescópio Espacial Spitzer dão base a um modelo do enigmático sistema, que identifica Epsilon Aur como uma estrela grande, mas de baixa massa apróxima ao final de sua vida, eclipsada periodicamente por uma estrela sozinha, em um disco de poeira. Estima-se que o disco tenha um raio de cerca de 4 AU, ou 4 vezes a distância entre a Terra e o Sol, e que tenha a espessura de 0.5 AU. 
Every 27 years Epsilon Aurigae fades, remaining dim for roughly two years before growing bright again. Since the 19th century, astronomers have studied the mystery star, eventually arguing that Epsilon Aur, centered in this telescopic skyview, was actually undergoing a long eclipse by a dark companion object. But the nature of the companion and even the state of bright star itself could not be pinned down by observations. Continuing to collect evidence, Citizen Sky, a team of professional and amateur astronomers, is studying the current eclipse of Epsilon Aur, reporting that it began in August 2009 and by late December had reached its deepest point. Epsilon Aur is now expected to remain dim for all of 2010, before rapidly regaining normal brightness in 2011. Meanwhile, recent infrared data from the Spitzer Space Telescope supports a model for the enigmatic system that identifies Epsilon Aur as a large but lower mass star near the end of its life, periodically eclipsed by a single star embedded in a dusty disk. The disk is estimated to have a radius of about 4 AU, or 4 times the Earth-Sun distance, and to be about 0.5 AU thick.
Every 27 years Epsilon Aurigae fades, remaining dim for roughly two years before growing bright again. Since the 19th century, astronomers have studied the mystery star, eventually arguing that Epsilon Aur, centered in this telescopic skyview, was actually undergoing a long eclipse by a dark companion object. But the nature of the companion and even the state of bright star itself could not be pinned down by observations. Continuing to collect evidence, Citizen Sky, a team of professional and amateur astronomers, is studying the current eclipse of Epsilon Aur, reporting that it began in August 2009 and by late December had reached its deepest point. Epsilon Aur is now expected to remain dim for all of 2010, before rapidly regaining normal brightness in 2011. Meanwhile, recent infrared data from the Spitzer Space Telescope supports a model for the enigmatic system that identifies Epsilon Aur as a large but lower mass star near the end of its life, periodically eclipsed by a single star embedded in a dusty disk. The disk is estimated to have a radius of about 4 AU, or 4 times the Earth-Sun distance, and to be about 0.5 AU thick.
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