microwaves in the search for interstellar communications, a component of the modern SETI program. This was one of the first proposals for detecting extraterrestrial intelligence. He conceded that "The probability of success is difficult to estimate, but if we never search, the chance of success is zero." Morrison remained at Cornell until 1964, when he went to the Massachusetts Institute of Technology (MIT). He remained there for the remainder of his career, becoming Institute Professor in 1976, and Institute Professor Emeritus in 1986. In 1963, working in collaboration with a student of his, James Felten, Morrison had investigated the effect of inverse Compton scattering, an important source of cosmic x-rays and gamma rays. At MIT, Morrison teamed up with Bruno Rossi's x-ray group there, and also with Riccardo Giacconi's group at nearby American Science and Engineering. Morrison became deeply involved in the exploration of the cosmos through its x-ray and gamma ray emissions. In a 1960 paper, he noted the similarities between pulsars and quasars. He returned to this in 1976, applying his model to the radio galaxy Cygnus A. Media work Morrison was known for his numerous books and television programs. He produced 68 popular science articles between 1949 and 1976, ten in issues of Scientific American. He provided the narration and script for Powers of Ten in 1977. With his wife, Phylis, they turned the same material into a coffee table book in 1982. He also appeared as himself in the science documentary film Target...Earth? in 1980. In 1987, PBS aired his six part miniseries, The Ring of Truth: An Inquiry into How We Know What We Know, which he also hosted. In addition, he was a columnist and reviewer of books on science for Scientific American starting in 1965. In later life he was a critic of the Strategic Defense Initiative. He authored or co-authored a number of books critical of the Cold War and the nuclear arms race, including Winding Down: The Price of Defense (1979), The Nuclear Almanac (1984), Reason Enough to Hope (1998) Beyond the Looking Glass (1993). Recognition Morrison was a fellow of the American Physical Society, and chairman of the Federation of American Scientists from 1973 to 1976. He was also a member of the National Academy of Sciences, the International Astronomical Union, the American Association of Physics Teachers, the American Academy of Arts and Sciences and the American Philosophical Society. Over