Death spiral and the other top astronomy photos of the year DEC 22 2010
Bad Astronomy lists its top fourteen astronomy photos of the year, including this nearly unbelievable spiral pattern caused by a binary star.
The object, called AFGL 3068, is a binary star, two stars in an 800-year orbit around one another. One of them is a red giant, a star near the end of its life. It's blowing off massive amounts of dark dust, which is enveloping the pair and hiding them from view. But the system's spin is spraying the material out like a water sprinkler head, causing this giant and delicate spiral pattern on the sky. And by giant, I mean giant: the entire structure is about 3 trillion kilometers (about 2 trillion miles) across.