One of the 20th century's most innovative physicists and science communicators died last Friday, April 22nd, at age 89. Philip Morrison will long be remembered as a designer of the first atomic bomb, a lifelong advocate for nuclear disarmament thereafter, a pioneering figure in high-energy astrophysics and cosmology, an originator of the search for extraterrestrial intelligence, and a public explainer of science through his numerous books and articles, his film "Powers of Ten," and his PBS television series "The Ring of Truth."
In 1945 Morrison helped to assemble, with his own hands, one of the atomic bombs dropped on Hiroshima and Nagasaki, then was part of the team that surveyed the cities a month later. The experience "stamped him for life," fellow MIT physicist Kosta Tsipis told the New York Times yesterday. Morrison went on to work in high-energy astrophysics, including the origins of cosmic rays. In 1959 he coauthored the seminal paper in Nature establishing the plausibility of what came to be called SETI using radio telescopes to search for evidence of other civilizations among the stars. He authored a long-running column in Scientific American with his wife Phylis, who died in 2002. See further obituaries by the Planetary Society (which he advised since its 1980 founding) and the New York Times.