They are joined in an epic cosmic waltz 9 billion light years away. what are they? Two supermassive black holes. They appear to be orbiting each other every two years. It’s an eye-catching spectacle: these are black holes merging.
In the middle of the galaxy
Long-term radio monitoring of a supermassive black hole was performed. It is located at the center of a galaxy. And it appears to show that it has a massive invisible companion.
The observations are led by Caltech, and were made over a 13-year period. They were made by the Owens Valley Radio Observatory in northern California. They reveal that the radio black hole will soon merge with a companion black hole. Together they will form a supermassive binary black hole (SMBHB).
These two supermassive black holes appear to be orbiting each other every two years. Each of the two giant bodies has masses that are hundreds of millions of times larger than that of our Sun. They are separated by a distance 50 times greater than that between our star and Pluto. The pair will merge in about 10,000 years. The titanic collision is expected to shake space and time itself, sending gravitational waves through the universe.
Many more
The observations are detailed in a paper appearing in The Astrophysical Journal Letters. The observed quasar is of a subclass called blazars in which the jet points toward Earth. It is the second known candidate for a pair of merging supermassive black holes.
“From an astrophysical perspective, we expect supermassive black hole binaries.” said Joseph Lazio. He is an astrophysicist at NASA’s Jet Propulsion Laboratory. And also one of the co-authors of the paper.
“Most large galaxies have supermassive black holes at their centers. Galaxies are observed to be undergoing mergers. And there should be supermassive black hole binaries as a result.” Merging black holes in full view of observers confirm this.
