Apod 2.7 The Mystery of the Fading Star

Epsilon Aurigae, a binary star and the fifth brightest star in the constellation Auriga, is very mysterious. Every 27 years, Epsilon Aurigae fades and stays dim for 2 years before returning to its normal magnitude. Epsilon Aurigae is being eclipsed by a single star embedded in a dusty disk. The disk is estimated to have a radius of four astronomical units and to have a thickness of .5 astronomical units. Epsilon Aurigae is currently undergoing the two-year long eclipse. Astronomers formed a team called Citizen Sky and are currently collecting data to help explain the nature of the companion star and the state of the brighter star, which couldn't be explained in previous observations. Spitzer Space Telescope, an infrared telescope, has observed Epsilon Aurigae and its data provides evidence that Epsilon Aurigae is a large, but low mass star near the end of its life cycle. The current eclipse will last throughout 2010 and in 2011 Epsilon Aurigae will rapidly return to its normal brightness.