Yesterday, the National Aeronautics and Space Administration, better known as NASA, announced that a supermassive black hole 9 billion light-years away appears to have a companion black hole orbiting around it and, as the orbit shrinks, the pair approaches fusion.
The first image of a black hole was the most important achievement of 2019. It is located at the center of the Galaxy Messier 87, at a distance of 55 million light years, and has the monstrous mass of 6.5 billion suns.
Supermassive black holes are millions of times the mass of the Sun and are at the heart of most galaxies. While most are thought to have resulted from at least one merger between two smaller black holes, scientists had not yet been able to prove it. Now, a new report published in The Astrophysical Journal Letters could change that: Recently, a team of researchers reported signs of a black hole that has a companion in close orbit. The huge duo, called binary, orbit each other every two years. If the team is correct, the diameter of the binary’s orbit is 10 to 100 times smaller than that of the only other known supermassive binary, and the pair will merge in about 10,000 years. Although it may seem like a lot of time, a pair like this would take a total of around 100 million years to start orbiting each other and eventually merge. So it is believed that they are already more than 99% of the way to a collision. The evidence for this comes from observations of radio telescopes located on Earth and, particularly, that the brightness of the material that ejects one of those holes (remember that these by themselves do not emit light) shows regular ups and downs as predictable as the ticking of a clock. This regular variation is the result of a second black hole pulling the first as they orbit each other every two years. To confirm this, the team had to look at data from the Owens Valley Observatory and the University of Michigan Radio Observatory (1980 to 2012) for more than a decade (from 2008 to 2019). The story would have stopped there, but then, Lead Author Sandra O’Neill took up the project in June 2021 and discovered additional data from the Haystack Observatory (1975 to 1983), which matched predictions of how brightness fluctuated over time.” This work is a testament to the importance of perseverance,” said Joseph Lazio of NASA’s Jet Propulsion Laboratory and author. “It took 45 years of radio observations to produce this result. Small teams, at different observatories across the country, took data week after week, month after month, to make this possible.”
