Charles Bailyn Is honored for work measuring galactic black holes
How do you weigh something you can’t even see? Charles Bailyn, the Thomas E. Donnelley Professor of Astronomy and Physics, knows how to do it.
Bailyn has been measuring the masses of black holes for more than 15 years, and now the American Astronomical Society (AAS) has awarded him the 2009 Bruno Rossi Prize in recognition of that research.
The Rossi Prize — which Bailyn will share with his two colleagues, Jeffrey McClintock at the Harvard-Smithsonian Center for Astrophysics, and Ronald A. Remillard at the Massachusetts Institute of Technology — is awarded annually by the AAS High Energy Astrophysics Division. The prize, established in honor of X-ray astronomy pioneer Bruno Rossi, is given “for significant contributions as well as recent and original work in high-energy astrophysics.”
“Winning the Rossi Prize is very exciting, and totally unexpected,” Bailyn says. “It’s wonderful recognition for a collaboration that’s been going on for a long time.”
Bailyn and his colleagues won the prize specifically for their research in measuring the masses of black holes that exist throughout the disk of our own Milky Way galaxy as well as in others. It was after the first black hole was detected by McClintock and Remillard in 1986 that Bailyn got interested in trying to track down the elusive and exotic objects. By the time the second was found in 1992, he was part of the team that made the discovery. More than 15 years later, there are about two dozen confirmed galactic black holes — about half of which were discovered by Bailyn and his team, which also includes his former graduate student, Jerry Orosz, now at San Diego State University.
Once Bailyn knew where the black holes were located, he set about trying to learn more about them, including how big they were. Most of the black holes in the “family portrait,” as he calls it, are between 5 and 15 times as massive as our own Sun — big by any standard, but much smaller than the supermassive black holes that lurk at the centers of galaxies. “They’re the biggest small black holes,” Bailyn joked.
While astronomers have only discovered a few dozen galactic black holes, they believe there could be anywhere from hundreds to tens of thousands more throughout the universe — promising many more years of discovery to come, notes Bailyn.
“This honor is well-deserved,” says Jeffrey Kenney, chair of the Department of Astronomy. “In addition to his excellent research, Charles has made enormous contributions to the astronomy department and the University, and is also a wonderful colleague, so I am thrilled the astronomical community has decided to recognize him in this way.”
In addition to the recognition the prize itself brings, Bailyn is happy it was awarded for research that didn’t require the biggest or most powerful telescopes in the world. “I like the vindication that small, ground-based telescopes can do big, important astronomy,” he says.
Bailyn, McClintock and Remillard will give a joint lecture at the AAS meeting in Washington, D.C., next January.