Astrophysicist John Bahcall, whose ideas about solar neutrinos paved the way for fundamental discoveries in astrophysics and particle physics, died from a rare blood disorder yesterday in New York City. He was 70.
Bahcall, along with Raymond Davis Jr., laid the foundations for neutrino astrophysics in 1964 by proposing that the number of neutrinos arriving upon Earth's surface could shed light on the sun's characteristics, such as its temperature and age. Experimental observations by Davis later showed a discrepancy between Bahcall's predictions and the number of neutrinos detected, which kicked off a 3-decade effort by scientists to solve what came to be known as the "solar neutrino puzzle." The effort ultimately led to the conclusion that neutrinos have mass and switch between different particle states. (ScienceNOW 18 June, 2001)
Aside from his individual contributions, Bahcall played a significant role in setting the course for the United States' astronomy endeavors in the 1970s and the 1980s, including the creation of the Hubble Space Telescope. He created the astronomy group at the Institute for Advanced Study (IAS) in Princeton, New Jersey, where he was a professor, and helped establish similar groups at Israel's Weizmann Institute and Tel Aviv University. Bahcall served as president of the American Astronomical Society from 1990 to 1992.
"Always generous with his time, John Bahcall was an inspirational teacher and mentor who shaped the careers of a generation of scientists," says IAS director Peter Goddard.
John Bahcall's home page at IAS