A pair of supermassive black holes, known as a binary black hole system, emitted a burst that was brighter than a trillion stars. The pair is located in galaxy OJ287 and is so close that it appears as a dot in the night sky.
Galaxy OJ287 is about 5 billion light-years from Earth in the direction of the Tropic of Cancer. It has been the focus of study by astronomers from the University of Turku since 1888, where astronomer Imo Cillanpa and his colleagues discovered a prominent pattern in its emission that has two cycles, one of about 12 years and one of about 55 years. A team of astronomers suggested that this was the result of the orbital motion of the two Black holes Close to each other, the short cycle is the orbital rotation and the long one is the result of the slow evolution of the orbital orientation.
In a press release, the team noted, „Orbital motion is revealed by the continuous flares that arise when the secondary black hole regularly sinks through the primary black hole’s accretion disk at a fraction less than the speed of light. .”
It is this „filling” of the secondary black hole that heats the disc material and releases the hot gas as expanding bubbles. As these extremely hot bubbles cool over a few months, they emit a blue flash, which the team discovered in early 2022.
„The total number of predicted flares now stands at 26, and all of them have been observed,” noted Professor Achamveedu Gopakumar of the Tata Institute of Fundamental Research in Mumbai, India. And, “Great black hole The pair is 18 billion times more massive than our Sun, the companion is approximately 100 times lighter and their orbits are elliptical, not circular.”
Professor Mauri Waldonen, lead author of the research paper, said that even with all the known observations, astronomers could not detect the pair separately because they converged at a single point in a telescope. Later, during observational campaigns of the galaxy OJ287 in 2021/2022, researchers were able to detect a secondary black hole penetrating the accretion disk for the first time, along with signals from the minor black hole.
According to previous predictions, when the secondary black hole sinks through the accretion disk, it will produce a blue glow immediately after impact. That blue light was observed within the predicted time by Martin Jelinek of the Czech Technical University and the Astronomical Institute of the Czech Republic.
Exciting observation yielded two more surprises, discovered by Staszek Zola of the Jagiellonian University in Krakow, Poland. First, it produced 100 times more light than an entire galaxy and lasted only one day. came from the second Gamma raysThe largest gamma-ray burst in OJ287 in six years occurs just as the minor black hole bursts through the gaseous disk of the primary black hole.
„So what,” Waldonen asked One day blast, why haven’t we seen it before?” He explained, „OJ287 has been recorded in photographs since 1888 and has been actively followed since the 1970s. It turns out that we were simply unlucky. On those nights when OJ287 did its one-night stint, no one noticed. Had it not been for the keen observation of the Zola team, we would have missed it this time.”