Astronomy Picture of the Day

Explanation: This expansive (1-degree wide) telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. It is centred on a bright hydrogen emission region recorded in the 1959 catalogue by astronomer Stewart Sharpless as Sh2-101. About 8,000 light-years distant the nebula is popularly known as the Tulip Nebula, understandably not the only cosmic cloud to evoke the imagery of flowers. Complex and beautiful in visible light, the area also includes one of the brightest, most famous sources in the x-ray sky, Cygnus X-1. Discovered in the early 1970s, Cygnus X-1 is a bizarre binary system consisting of a massive, hot, supergiant star (seen here) in close orbit with a stellar mass black hole. The Cygnus X-1 system is also estimated to lie a comfortable 8,000 light-years away.