Scientists have discovered an object in space whose brightness does not fit into the modern scientific paradigm. It shines 570 billion times brighter than the Sun. The light is 20 times brighter than the Milky Way galaxy, with all its stars and planets.
ASASSN-15lh is located 3.8 billion light-years from Earth. It was discovered during the automatic search for supernovae. So bright that it pushes the energy limit of physics.
Astrophysicists still cannot understand what could have become a source of such powerful energy – unusual even for a supernova. According to one hypothesis, the object at the center of the structure is a magnetar, an extremely rare type of star.
But this hypothesis may not be confirmed. If the object is in the center of a large galaxy, it is definitely not a magnetar or a supernova.
“If it really is a magnetar, it’s as if nature took everything we know about magnetars and turned it up to 11,” said Krzysztof Stanek, professor of astronomy at Ohio State University and the team’s co-principal investigator, comedically implying it is off the charts on a scale of 1 to 10.
“We have to ask, how is that even possible?” said Stanek. “It takes a lot of energy to shine that bright, and that energy has to come from somewhere.”
Over the coming months, the Hubble Space Telescope will try to solve this mystery by giving astronomers time to see the host galaxy surrounding this object. The team may find that this bright object lies in the very center of a large galaxy — meaning the object is not a magnetar at all — and the gas around it is actually evidence of a supermassive black hole.
If that is the case, then the bright light could be explained by a new kind of event, said study co-author Christopher Kochanek, professor of astronomy at Ohio State. It would be something that has never, ever been seen before at the center of a galaxy.
Whether it is a magnetar, a supermassive black hole, or something else entirely, the results are probably going to lead to new thinking about how objects form in the universe.