The first known Black Hole is more Massive than thought

New observations of the first black hole ever detected have led astronomers to question what they know about the most mysterious objects in the Universe.Published in the journal Science, the research shows that the system known as Cygnus X-1 contains the most massive stellar-mass black hole ever detected without the use of gravitational waves.

Cygnus X-1 is one of the closest black holes to Earth. It was discovered in 1964 when a pair of Geiger counters were transported aboard a suborbital rocket launched from New Mexico.

The object was the focus of a famous scientific bet between physicists Stephen Hawking and Kip Thorne, with Hawking betting in 1974 that it was not a black hole. Hawking granted the bet in 1990.

In this latest work, an international team of astronomers used the Very Long Baseline Array, a radio telescope the size of a continent made up of 10 plates scattered across the United States, along with a clever technique for measuring distances in space.

“If we can see the same object from different locations, we can calculate its distance from us by measuring how far the object appears to be moving relative to the background,” lead researcher Professor James Miller-Jones of Curtin University said in a statement. and the International Center for Radio Astronomy Research (ICRAR).

“If you place your finger in front of your eyes and see it with one eye at a time, you will notice that your finger seems to jump from one place to another. It is exactly the same principle.”

“For six days we observed a complete orbit of the black hole and we used observations taken from the same system with the same set of telescopes in 2011,” said Professor Miller-Jones. “This method and our new measurements show that the system is further away than previously thought, with a black hole that is significantly more massive.”

Co-author Professor Ilya Mandel of Monash University and the ARC Center of Excellence in Gravitational Wave Discovery (OzGrav) said that the black hole is so massive that it actually challenges how astronomers thought it formed.

“Stars lose mass in their environment through stellar winds blowing from their surface. But to make such a heavy black hole, we need to reduce the amount of mass that bright stars lose during their lifetime,” he said.

“The black hole in the Cygnus X-1 system began life as a star about 60 times the mass of the Sun and collapsed tens of thousands of years ago,” he said. “Incredibly, it is orbiting its companion star, a supergiant, every five and a half days at only one-fifth the distance between Earth and the Sun.”

“These new observations tell us that the black hole is more than 20 times the mass of our Sun, a 50 percent increase from previous estimates.”

Xueshan Zhao is a co-author of the article and has a PhD. candidate studying at the National Astronomical Observatories, part of the Chinese Academy of Sciences (NAOC) in Beijing.

“Using updated measurements of the black hole’s mass and its distance from Earth, I was able to confirm that Cygnus X-1 spins incredibly fast, very close to the speed of light and faster than any other black hole found to date.” He said.