An eclipsing binary with a very long orbital period (9892 days) and many unusual characteristics. A visible star, now thought to be an F0 giant, is eclipsed for approximately 610 days by a larger, unseen object. This dark companion is thought to consist of a B5 main-sequence star surrounded by a disk of dust and gas with a radius of about 4 au seen virtually edge-on. During eclipses, the apparent magnitude falls from 3.0 to 3.8. Epsilon Aurigae is about 2000 l.y. away. The last eclipse was in 2009–11; the next is due to start in 2036.