The Fate of the First Black Hole

The Canadian rock band Rush knows its astronomy. In a lengthy 1977 song, the musicians proclaimed Cygnus X-1, an x-ray emitting object thousands of light-years away, a black hole where voyagers venture "through the void to be destroyed"—even though physicist Stephen Hawking had bet against the black hole's existence. This year, astronomers proved Rush right by establishing 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.