Scientists have detected millions of previously hidden supermassive black holes surrounding us, some of them busily eating newly discovered “extremely bright and extremely rare” galaxies called hot DOGs (Dust-Obscured Galaxies). Astronomy is fun!
Using NASA’s Wide-Field Infrared Survey Explorer, astronomers have been able to locate a staggering amount of these supermassive black holes: about 2.5 million. These quasars were hidden before because of dust clouds, but NASA is quickly uncovering them thanks to WISE’s Nuclear Spectroscopic Telescope Array (NuSTAR). According to Jet Propulsion Laboratory’s Daniel Stern:
We’ve got the black holes cornered. WISE is finding them across the full sky, while NuSTAR is giving us an entirely new look at their high-energy X-ray light and learning what makes them tick.
Quasars start their life as dead colossal stars that collapse at the end of their lives, attracting mass around them until they grow into supermassive hungry beasts, feeding on whatever gas and dust surrounds them, becoming more and more massive in a never-ending cycle. As the quasar eats, it gets extremely hot, emitting light that can be captured by WISE’s instruments.
These mighty black holes are also found in the hearts of these rare galaxies, so bright and hot that they emit 100 trillion times as much light as the Sun.
We couldn’t see the blackholes or these galaxies with normal telescopes because they are obscured by dust. Only WISE, with its infrared instruments, has been able to detect these hidden fiery furnaces.
Both discoveries have been quite surprising. According to Jingwen Wu, a JPL scientist who lead one of the research papers, “we may be seeing a new, rare phase in the evolution of galaxies.” So rare, in fact, that Peter Eisenhardt — project scientist for WISE at JPL — says that “these dusty, cataclysmically forming galaxies are so rare WISE had to scan the entire sky to find them. What is more amazing, according to Eisenhardt, is that they are seeing that some of the galaxies “may have formed their black holes before the bulk of their stars.”
“The eggs may have come before the chickens.”
So much talk about eggs, chickens and hog dogs just made me hungry. [NASA]