Depending on the circumstances, this endgame collapse is sometimes marked by an amazing supernova explosion. In this case, Dr. However, Miller-Jones in an email: “We believe that the black hole was formed by almost direct collapse into a black hole and not by a type II supernova explosion.” Such an explosion, he said, would have the double star pair thrown from a cluster of similarly massive stars in which it has formed and apparently still lives.

Since then, the black hole has been feeding itself and drawing gas from its inflated neighbor who, according to Dr. Miller-Jones has a lot to give with around 40 solar masses.

The new measurement of the mass of Cygnus X-1 was accidental. “We didn’t set out to remeasure the distance and mass of the black holes,” said Dr. Miller-Jones. “But when we analyzed our data, we saw its full potential.”

In the spring of 2016, Dr. Miller-Jones and his group spent six days using Cygnus X-1 with the National Radio Astronomy Observatory’s Very Long Baseline Array, a statewide network of antennas operated out of Socorro, New Mexico connecting x-ray emitting gas going into the black Hole flows, and high-speed radio beams shooting out of it.

However, part of the process allowed them to triangulate the distance to Cygnus X-1 and increase it from about 6,000 light years to just over 7,000. Interestingly, according to Dr. Miller-Jones, the distance also agreed better with the early results of the European Space Agency’s Gaia Space Telescope, whose measurements were in slight tension with the previously accepted distance.

When this change in distance was included in the luminosity and mass calculations, the estimated mass of the black hole grew by about 40 percent to 21 solar masses.