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Riccardo Giacconi Awarded Nobel Prize For Pioneering Work In X-Ray Astronomy

10 October 2002

Riccardo Giacconi
Riccardo Giacconi, who shared in Nobel Prize for Physics in 2002 for his contribution to X-ray Astronomy. This photo was taken on the occasion of his festschrift in 1997.

More than 100 years ago, the first Nobel Prize in physics was awarded to Wilhelm Röntgen for his discovery of X-rays. This week, Riccardo Giacconi was recognized with a share in the Nobel Prize in physics for his pioneering work in X-ray astronomy.

Giaconni, president of the Associated Universities Inc., in Washington, and Research Professor of Physics and Astronomy at Johns Hopkins University, Baltimore, discovered the first X-ray stars and the X-ray background in the 1960s and conceived of and led the implementation of the Uhuru and High Energy Astronomy Observatory-2 (HEAO-2) X-ray observatories in the 1970s. With funding from NASA, he also detected sources of X-rays that most astronomers now consider to contain black holes.

Giacconi said that receiving the award confirms the importance of X-ray astronomy. "I think I'm one of the first to get the Nobel prize for work with NASA, so that's good for NASA and I think it's also good for the field," he said. "It's also nice for all the other people who've worked in this field. I recognize that I was never alone. I'm happy for me personally, I'm happy for my family, and I'm happy for the field and for NASA," Giacconi added.

In 1976, Giacconi along with Harvey Tananbaum of the Harvard- Smithsonian Center for Astrophysics, Cambridge, Mass., submitted a proposal letter to NASA to initiate the study and design of a large X-ray telescope. In 1977 work began on the program, which was then known as the Advanced X-ray Astrophysics Facility and in 1998 renamed the Chandra X-ray Observatory.

"Partnerships with universities and scientists are essential in our quest to answer the fundamental questions of the universe," said Dr. Ed Weiler, NASA Associate Administrator for Space Science, Headquarters, Washington. "Dr. Giacconi's achievements are a brilliant example of this synergy among NASA, universities and their community of scientists and students," he said.

Giacconi is Principal Investigator for the ultradeep survey with Chandra -- the "Chandra Deep Field South" -- that has already obtained the deepest X-ray exposures to date with a million-second observation. He was also the first director of the Hubble Space Telescope Science Institute in Baltimore.

Giacconi, 71, received half the $1 million prize. Raymond Davis Jr., 87, of the University of Pennsylvania and Masatoshi Koshiba, 76, of the University of Tokyo share the other half of the prize for their research into cosmic neutrinos.

Additional Links

starRead more about the Nobel Prize. (

starRead more about Giacconi's Festschrift. (

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