The Fate of the First Known Black Hole

sciencehabit writes "Cygnus X-1 bears its name because it was the first source of x-rays found in the constellation Cygnus. In 1971, astronomers discovered that the x-rays came from the direction of a bright blue star whirling around a mysterious dark object. They speculated that the x-rays were resulting from material being torn away from the bright star and falling onto the dark object, perhaps a black hole. This year, astronomers established that Cygnus X-1 does indeed harbor a black hole, a dead star whose great gravity lets nothing, not even light, escape. Now that result has inspired a forecast for the system's future: The black hole will swallow even more mass from an unfortunate star circling it, then likely dash away on its own when its companion explodes."

Comments

Re:if black holes attract light

[Chris Burke]

This is a corollary of relativistic mass-energy equivalence (E=mc^2).

A lot of people (and I sympathize because I was one of them for years) mistakenly believe that E=mc^2 is about the energy content of matter, and how you could convert mass to energy via, say, matter/anti-matter annihilation. Which when thought of as converting one form of energy to another is true, but hides the deeper truth: Matter isn't just a type of energy that has mass, all energy has mass, they are really the same thing.