15 NOVEMBER 00

John Reynolds
John Reynolds, professor emeritus of physics and a pioneer in the isotopic dating of rocks and meteorites, died at his home in Berkeley, Nov. 4, at the age of 77. He was recovering from pneumonia when he suffered a pulmonary embolism.

Reynolds had been a member of the College of Letters & Science faculty since 1950, served as chairman of the physics department from 1984 to 1986, and retired in 1993.

He is best remembered for his research on isotopic and elemental measurements of the noble gases - helium, argon and xenon - which made it possible to determine the age of both terrestrial rocks and meteorites.

These accurate measurements provided a reliable chronology for the early solar system. Among the surprises was that the Earth had formed a relatively short time - between 120 and 290 million years - after its gas and dust were produced in a nearby supernova explosion.

Born in 1923, in Cambridge, Mass., he attended Harvard College as an undergraduate, and received a Ph.D. in physics from the University of Chicago in 1950. He served with the U.S. Navy in the South Pacific during World War II.

Reynolds received numerous distinctions in his career, including the J. Lawrence Smith Medal of the National Academy of Sciences; the NASA Exceptional Scientific Achievement Medal; the Leonard Medal from the Meteoritical Society; Doctor, Honoris Causa from University of Coimbra, Portugal; the National Science Foundation Cooperative Research Award and the Berkeley Citation.

He is survived by his wife, Ann Reynolds, and children Petra of San Jose; Karen Stein, Brian and Horace of Berkeley; and Amy of San Francisco. A memorial service will be held at the Faculty Club at 4 p.m., Nov. 16. Contributions may be sent to the Department of Physics, LeConte Hall, University of California, Berkeley, CA 94720-7300 and to The Visiting Nurses Association.