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issued by Stanford University

June 18, 2004, Stanford, CA -- In an article posted June 10 to the Astrophysical Journal Letters website, astrophysicists at Stanford report spotting a black hole so massive that it's more than 10 billion times the mass of our sun. More important, this heavyweight is so far away that the scientists think it formed when the universe first began to light up with stars and galaxies, so it may provide a window into our cosmological origins.

"In cosmology, it turns out that 'a galaxy a long time ago' and 'far, far away' really do go together," says Associate Professor Roger Romani, who with graduate student David Sowards-Emmerd and Professor Peter Michelson of Stanford, and radio astronomer Lincoln Greenhill of the Harvard-Smithsonian Center for Astrophysics, spotted one of the oldest supermassive black holes yet found. The scientists collaborate at the Kavli Institute for Particle Astrophysics and Cosmology at Stanford. "In this case, we're looking at [a black hole] far enough away that it's within a billion years of the origin of it all, the Big Bang."

The supermassive black hole sits in the center of a galaxy. A disk of stars and gas swirl around the black hole and eventually get sucked in. "That generates enormous amounts of power, enormous amounts of energy," Romani says. "It's far more efficient even than nuclear fusion. These gravity-powered sources are the most powerful sources in the universe."

As black holes go, this one is a messy eater. It's Jabba the Hutt, in fact, gobbling up its galaxy so quickly that not everything is making it down its throat past the point of no return -that place, called the "event horizon," where not even light can escape gravity's strongest pull. The matter that doesn't make it past the event horizon is spewing back up in the form of accelerated high-energy particles.

If a black hole amid a galaxy shoots out high-energy particles in narrow jets that just happen to be aimed at Earth, astrophysicists give the whole thing a special name - "blazar." Amazingly , these blazars can be detected at nearly all energies, even at the high energy of gamma rays. In fact, distant blazars seem to dominate the gamma-ray sky and can obscure other objects of interest . Pulsars, spinning neutron stars nearby in our own galaxy, can also emit gamma rays, but far fewer of them are known. Romani, whose main interest is pulsars, wanted to identify and discard blazars so he could concentrate on the neutron stars.

"I got started working on the blazars as a way of culling the wheat from the chaff," Romani says. "But then the chaff proved just as interesting."

In preparation for a mission that is scheduled to launch in 2007, the co-authors have surveyed 200 blazars; eventually they hope to survey 2,000. The mission, led by Michelson, will use the Gamma Ray Large Area Space Telescope (GLAST) to study high-energy sources of radiation in the universe, such as supermassive black holes, merging neutron stars and hot streams of gas moving at nearly the speed of light. It is funded by NASA, the U.S. Department of Energy and government agencies in France, Italy, Japan and Sweden.

"Something really new is waiting to be found in the gamma-ray sky," Romani says. "If we could identify all the blazars, tag the pulsars - the things that are left over, that's where the really new discoveries will be."