There's A "Dark Disk of Material" Hovering Out In Space


Some kind of obstruction is blocking our view of Epsilon Aurigae, a star in the constellation Auriga. Its exact nature is unknown — but astronomers say that if you've got a telescope, you could help them figure it out.

Epsilon Aurigae is a binary system, or a star locked in a pattern of mutual orbit with a second body. It lies in the constellation Auriga, about two thousand light-years away from Earth. We like this star, because it gives us the chance to shout out to some old-school Green Day.

About every twenty-seven years, Epsilon Aurigae undergoes an eclipse that lasts between twenty and twenty-four Earth months. During this time, the light from the star dims appreciably. Astronomers aren't sure what causes the eclipse; they believe it's the companion body in the binary system, but there's disagreement as to what exactly that body might be.

One popular school of thought is that the orbiting, eclipsing body is a huge disk of... something. Possibly dust and space debris, but really, no one is sure. Robert Stencel, a professor of astronomy at Denver University and longtime studier of Epsilon Aurigae, described the mystery object as "a dark disk of material" in a recent press release. "The exact shape and makeup of the disk has been unknown," said Stencel, "but it will be better defined soon."

"Soon," because there's another eclipse happening right now, and that affords us the chance to study the phenomenon again. This is where you and I come in, if we have any stargazing equipment. A project called Citizen Sky has put out an open call for amateur astronomers to watch Auriga and contribute information on the mysterious star-blocker. (Stencel is a team member of Citizen Sky, in addition to his professorial duties. He wears many hats, it seems.)

Epsilon Aurigae is so bright that it can be seen from just about anywhere on Earth, so if you're of a mind, head over to the Citizen Sky site and see whether it looks interesting. If it turns out — and I'm just going to say what we're all thinking here — if it turns out that the object orbiting Epsilon Aurigae is an alien mothership of some kind, and you're the first to identify it as such, then there's a decent chance you could get the thing named after yourself.

Image by Nico Camargo and courtesy www.citizensky.org. Used under Creative Commons license.