LB-1 Stellar Black Hole Milky Way Galaxy
Photo credit: Jingchuan Yu
Astronomers in China have discovered LB-1, a stellar black hole that is so massive it shouldn’t exist based on our current theories of black-hole formation. It has a mass 70-times that of our sun, but astronomers had previously believed that stellar black holes in our galaxy could not be bigger than 20-times the mass of the sun. A team used the LAMOST telescope in China and discovered some stars orbiting an invisible object and with other telescopes in Spain and the U.S., the astronomers pinpointed one star orbiting the black hole every 79 days. Read more for a video and additional information.



The Chinese team theorized the black hole gotten so large because it could have been formed by the collapse of more than one star. Other black holes that are larger than LB-1 have been discovered, such as the supermassive black hole in the center of the Milky Way, but this one was the largest of its kind.

Black holes of such mass should not even exist in our Galaxy, according to most of the current models of stellar evolution. We thought that very massive stars with the chemical composition typical of our Galaxy must shed most of their gas in powerful stellar winds, as they approach the end of their life. Therefore, they should not leave behind such a massive remnant. LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation,” said Professor Liu Jifeng, who led the research.