Agalxia OJ 287, which is 3.5 billion light-years from Earth, made up of two black holes, which NASA describes as damaging each other. Every 12 years they hatch, generating an explosion of visible light from our planet, which according to scientists, is equivalent to the radiation of a billion stars.
As NASA says in its blog, the phenomenon was recorded by the Spitzer telescope, explaining that the main supermassive black hole, being located in the center of the galaxy. This is 18 billion times more massive than the Sun, being one of the largest that the space agency has ever detected. Its companion is a smaller black hole, but still, 150 million times more massive than the Sun.
In the video you can see a simulation that NASA created to explain the phenomenon.
NASA compares black holes to a dance because they are not stopped in space, but with very active movements. But being black, they cannot be observed directly, which makes their study difficult. However, as mentioned, twice every 12 years, the small black hole collides with the gigantic disk of gas that surrounds the largest. Because they have an irregular 12-year orbit, black holes collide at different times in their cycle.
This shock creates a flash of light even brighter than the entire Via Lctea, taking 3.5 billion years to reach Earth. NASA explains that when the shock occurs, two clouds of hot gas are created that move from the disk in opposite directions. In less than 48 hours, the system's brightness seems to quadruple in intensity.
Because it is a phenomenon that occurs every 12 years, it is difficult to record its prediction, but recently a group of scientists carried out a study that claims that the last shock happened on July 31, 2019, captured by the Spitzer telescope. It was one of the last records of the telescope before its renovation in January.