Dancing black holes create mega flare brighter than one trillion stars

In the OJ 287 galaxy, about 3.5 billion light years from Earth, two black holes are caught in an endless dance. The super-massive black hole at the center of the galaxy is about 18 billion times as massive as the sun – one of the largest black holes we’ve ever found. The dance partner, much smaller but still huge, is only 150 million times as massive as the sun.

Every 12 years the smaller dancer falls through a huge debris disk that swirls around the super-massive black hole. When it does, it creates an explosion of light that we can visualize from behind on Earth because it is brighter than one trillion Stars. A mega torch. This epic animation from NASA’s Jet Propulsion Laboratory captures the phenomenon perfectly.

But the dance is kind of awkward.

The smaller black hole does not have perfect timing. Due to its elongated orbit, it falls through the window at irregular intervals, which makes it difficult for scientists to observe exactly when the next light explosion could occur. In 2010, a team of researchers set out to create a model to predict when they would see the next mega torch next time. Her model correctly predicted the occurrence of a torch within three weeks.

Then, in 2018, scientists from the Tata Institute for Basic Research in Mumbai, India, were able to refine the model to predict that the next torch would peak on July 31, 2019. They wrote that if they could see the flare, they could have a good opportunity to test the “no-hair theorem” that black holes are smooth and symmetrical.

A new study published on Tuesday in the Astrophysical Journal Lettersshows that the scientists’ predictions of when the torch would appear were just right – and luckily, NASA’s Spitzer telescope looked at OJ 287 at the right time.

“When I first checked the visibility of OJ 287, I was shocked to see that it became visible to Spitzer on the very day the next flare was predicted,” said Seppo Laine, Associate Scientist at Spitzer in Caltech. in a publication. Especially sharpener, who retired in January this yearwas the only telescope with a clear view of the galaxy at the time of the torch.

“It was very fortunate that we were able to use Spitzer to capture the peak of this torch because at that point in time no other man-made instrument was able to do this feat,” said Laine.

And Spitzer’s happy look provided further evidence for the no-hair theorem. Scientists’ predictions of when the torch would peak gave them more precise information about the cosmic dancers and the orbit of the smaller black hole. Since the smaller black hole crashed through the debris disk exactly as scientists predicted, this suggests that OJ 287’s supermassive black hole is symmetrical and smooth. A win for the no-hair theorem.

This dance will end up in disaster. The orbit of the smaller black hole decreases over time and brings it closer to its dance partner. The super-massive black hole will devour its smaller dance partner sometime in the next 10,000 years.