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Published on Nov 21, 2011
Astronomers have more precisely determined the spin, mass and distance of what they are confidently calling a stellar-mass black hole in the Cygnus X-1 system. Hawking bet against its existence three decades ago. Take a guided tour of the system. Credit: NASA/CXC/M.Weiss - To View More SPACE VIDEO - Go to: http://www.space.com/video/