Researchers searching for black holes across billions of light-years of space have stumbled upon what may be the fastest-growing and most luminous one ever seen. The supermassive black hole, observed as it appeared some 12 billion years ago, is the size of 20 billion suns — and extremely hungry.
According to a study soon to be featured in the Publications of the Astronomical Society of Australia, the black hole was growing by 1 percent every million years, devouring gas, dust, stars, and other celestial objects equivalent to the mass of our sun every two days.
"This black hole is growing so rapidly that it's shining thousands of times more brightly than an entire galaxy, due to all of the gases it sucks in daily that cause lots of friction and heat," study co-author Dr. Christian Wolf from the ANU Research School of Astronomy and Astrophysics said in a release.
The light emitted from these supermassive black holes, also known as quasars, is so violently bright that, if this particularly behemoth was situated at the center of our own galaxy, it would appear 10 times brighter than a full moon and wash out nearly all competing star light. (This spectacle would also carry the downside of destroying all life as we know it.)
"If this monster was at the centre of the Milky Way, it would likely make life on Earth impossible with the huge amounts of X-rays emanating from it," Wolf added.
A riddle in time
Technically known as QSO SMSS J215728.21-360215.1 (or J2157-3602 for short), the gigantic black hole was discovered using data collected by the European Space Agency Gaia satellite, the NASA Wide-field Infrared Survey Explorer (WISE), and the ANU SkyMapper telescope. While other giant quasars have been detected before, researchers are puzzled how this one managed to grow so large in so short a period of time.
According to Wolf, average black holes are about the size of 50 suns. Based on this one's current rate of growth, he posits that it must have started with a mass of nearly 5,000 suns.
"So, either black holes can grow faster than the speed limit — but we don't know how that works, and we have not seen it yet in action — or there is an unknown way to make 5,000 solar mass black holes very close in time to the Big Bang," Wolf told CNN. "But who knows what happened in the dark early ages of the universe?"
Because hungry supermassive black holes are exceedingly rare to discover, the researchers are hopeful that the data gathered on J2157-3602 will help guide them in spotting other giants lurking in the cosmos.
"We don't know how this one grew so large, so quickly in the early days of the universe," Wolf said. "The hunt is on to find even faster-growing black holes."