The supermassive black hole at the center of our galaxy is becoming increasingly hungry – and scientists have no idea why.
UCLA researchers were surprised to discover that the black hole called Sagittarius A * has been consuming an unusually large amount of interstellar gas and dust since May.
Professor Andrea Ghez, co-senior author of the study, said, "We've never seen anything like it in the 24 years we studied the supermassive black hole. It is usually a fairly quiet, weak black hole on a diet. We do not know what drives this big party. "
In the study, scientists analyzed more than 13,000 black hole observations from 133 nights since 2003.
Their analysis revealed that on May 13, the area just outside the "no return point" of the black hole (the area where matter can no longer escape) is twice as bright as normal.
Tuan Do, principal author of the study, said, "The first picture I saw that night, the black hole was so bright that I initially thought it was the star S0-2 because I've never seen Sagittarius A * so bright would have. But it quickly became clear that the source had to be the black hole, which was really exciting. "
This brightness is caused by the radiation of gas and dust falling into the black hole, indicating that it is hungrier than usual.
While the reason for this remains unclear, the team has several theories.
One idea is that the star S0-2, as it approached the black hole last year, emitted a large amount of gas that reached the black hole this year.
Another possibility is a strange object called G2, which approached shooter A * in 2014.
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During this approach, the black hole may have cleared the outer layer of G2, which, according to the researchers, could help explain the increased brightness.
Alternatively, the lightening may be due to swallowing large asteroids from the black hole.
Luckily, the researchers have assured that the black hole is not a threat to the earth.
The team hopes that further observations will help clear up the strange behavior.
Professor Ghez added, "We want to know how black holes grow and affect the evolution of galaxies and the universe. We want to know why the supermassive hole gets brighter and how it gets brighter. "