Scientists have all manner of ways to measure things around us in the universe, and so they can immediately notice when something doesn’t fit a pattern. A black hole in the galaxy SAGE0536AGN (we know, poetic) has defied all preconceptions about the size of a black hole relative to its galaxy.
SAGE0536AGN was initially discovered with Nasa’s Spitzer Space Telescope in infrared light, and is thought to be at least nine billion years old. It contains within it an incredibly bright object – called an active galactic nucleus – caused by gas being accumulated by a central supermassive black hole. Because of the size of the black hole, its immense gravitational field pulls the gas in at incredible speeds, causing the light to be emitted.
By measuring the speed of the gas moving around the black hole, astronomers at Keele University and the University of Central Lancashire have been able to discern its size. And it was a surprise.
“Galaxies have a vast mass, and so do the black holes in their cores. This one though is really too big for its boots — it simply shouldn’t be possible for it to be so large,” said Dr Jacco van Loon, an astrophysicist at Keele University and the lead author on the new paper.
So scientists are now pondering whether the black hole has been growing quicker than the galaxy, or whether the galaxy stopped growing prematurely. The galaxy was actually found by accident, so there’s a chance we could find many more like it – but until then we won’t know whether this galaxy really is as strange as it seems, or whether it’s just the first we’ve found of an entirely new breed of galaxy.
The research was published in the Monthly Notices of the Royal Astronomical Society.