An illustration of the Cygnus X-1 system shows a black hole drawing matter off a nearby star. The infalling material creates a disk around the black hole that emits powerful x-rays, which were first detected more than 50 years ago.
Using the multiple radio observatories that make up the National Science Foundation's Very Long Baseline Array, astronomers recently collected enough data to paint a more accurate picture of the black hole in the famous system.
The scientists calculate that the black hole lies 6,070 light-years from Earth, is more than 15 times as massive as our sun, and is spinning more than 800 times a second.
Published November 25, 2011
nationalgeographic.com