John N. Bahcall

John N. Bahcall
John N. Bahcall
Born	(1934-12-30)December 30, 1934 Shreveport, Louisiana
Died	August 17, 2005(2005-08-17) (aged 70) New York City, New York
Nationality	American
Known for	solar neutrino problem Hubble Space Telescope
Scientific career
Fields	astrophysics
Institutions	Institute for Advanced Study

John Norris Bahcall (December 30, 1934 – August 17, 2005) was an American astrophysicist, best known for his contributions to the solar neutrino problem, the development of the Hubble Space Telescope and for his leadership and development of the Institute for Advanced Study in Princeton.

Early and family life

Bahcall was born in Shreveport, Louisiana. He did not take science classes at high school. He was high school state tennis champion and a national debate champion. Bahcall began his university studies at Louisiana State University as a philosophy student on a tennis scholarship, where he considered becoming a rabbi. He transferred to the University of California, Berkeley, still studying philosophy. He took his first physics class as a graduation requirement.

He was married to Princeton University astrophysics professor Neta Bahcall, whom he met as a graduate student at the Weizmann Institute in the 1960s. They had a daughter and two sons. He died in New York from a rare blood disorder.

Academic career

He was graduated with an A.B. in Physics from Berkeley in 1956, obtained his M.S. in physics in 1957 from the University of Chicago and his Ph.D. in physics from Harvard in 1961. He became a research fellow in physics at Indiana University in 1960 and worked at the California Institute of Technology from 1962 to 1970, where he worked alongside Richard Feynman, Murray Gell-Mann, and William Fowler.

He was appointed professor at the Institute for Advanced Study in Princeton in 1971. He became a member of the National Academy of Science in 1976. He was president of the American Astronomical Society from 1990-1992, and was president-elect of the American Physical Society at the date of his death.

Research

Bahcall is most notable and most renowned for his work in establishing the Standard Solar Model. He spent much of his life pursuing the solar neutrino problem with physical chemist Raymond Davis, Jr. Together, Davis and Bahcall collaborated on the Homestake Experiment, creating an underground detector for neutrinos in a South Dakota gold mine -- essentially a very large tank filled with cleaning fluid. The flux of neutrinos found by the detector was 1/3 the amount theoretically predicted by Bahcall, a discrepancy that took over 30 years to resolve. The 2002 Nobel Prize in physics was awarded to Davis and Masatoshi Koshiba for their pioneering work in observing the neutrinos predicted from Bahcall's solar model, thereby vindicating Bahcall's prediction.

Bahcall's other contribution of great significance to astrophysics was the development and implementation of the Hubble Telescope, in collaboration with Lyman Spitzer, Jr., from the 1970s through to the period after the telescope was launched in 1990. In 1992, he received NASA's Distinguished Public Service Medal for this work.

He worked in many other areas. The standard model of a galaxy, with a massive black hole surrounded by stars, is known as the Bahcall-Wolf model. The Bahcall-Soneira model was for many years the standard model for the structure of the Milky Way. He also contributed to accurate astrophysical models of stellar interiors. Bahcall published over 600 scientific papers and five books in the field of astrophysics.

Honors

• Helen B. Warner Prize (1970)
• Fellow of the American Academy of Arts and Sciences (1976)
• NASA Distinguished Public Service Medal (1992)
• Heineman Prize (1994)
• Hans Bethe Prize (1998)
• National Medal of Science (1998)
• Henry Norris Russell Lectureship (1999)
• Dan David Prize (2003)
• Gold Medal of the Royal Astronomical Society (2003)
• Fermi Award (with Raymond Davis, Jr) (2003)
• Benjamin Franklin Medal (2003)
• Academy of Achievement, Golden Plate Award (2004)
• Comstock Prize in Physics from the National Academy of Sciences (2004)

Quotes

• "I know all about neutrinos, and my friend here knows about everything else in astrophysics." -- Bahcall's standard phrase on introducing himself and a colleague to a new acquaintance
• "I feel like dancing I'm so happy." -- when asked by a New York Times reporter how he felt about his solar neutrino theory being vindicated

External links

• Institute for Advanced Study:
  • Homepage
  • Biography
  • Press release following his death
• PBS Nova: The Ghost Particle
• Letter from his family after his death
• Dan David Prize laureate 2003

• Obituaries
  • Obituary (Nature, 1 September 2005) (PDF)
  • Obituary (Washington Post, August 20, 2005)
  • Obituary (New York Times, August 19, 2005) (Microsoft Word)
  • Obituary (The Times, 1 September 2005)