Biggest Black Hole Blast Ever Could Solve Cosmological Mystery
Astronomers have seen a distant galaxy that blasts away material with two trillion times the energy the sun emits — the biggest such eruption ever seen. That ejection of matter could answer an important question about the universe: why are the black holes in the centers of galaxies so light?
Image: Artist’s impression of the huge outflow ejected from the quasar SDSS J1106+1939 Credit: ESO/L. Calçada
Computer models of the early universe usually produce a virtual cosmos that looks like ours except for one thing. The ratio of the mass of black holes in galaxy centers to the rest of the matter in galaxies is larger in the simulations than in the real universe.
Scientists think somehow galaxies are ridding themselves of much of the mass that would have ended up falling into their central black holes. However, until now researchers have been at a lack for an explanation of how this might happen.
To expel matter from galaxies takes energy. “We needed some input of energy from supermassive black holes,” Nahum Arav, an astrophysicist at Virginia Tech.
Supermassive black holes are obvious candidates, because they are the most energetic objects known. Some galaxies containing active black holes, called quasars, shine more brightly than anything else in the universe. “Our simulations showed that if we allowed the quasar to release a lot of mechanical energy, then the masses of galaxies would match observations,” Arav said.
Arav led a team that observed a quasar, called SDSS J1106+1939, which dates back to when the universe was only 3 billion years old (it is now about 13.7 billion years of age). Most quasars are millions or even billions of light-years distant, which means we see them as they were long ago. As such, they offer a unique window back in time, to when galaxies were young.