Joseph Kaplan (September 8, 1902 – October 3, 1991) was a Hungarian-born American physicist. Kaplan was notable for his studies of atmospheric phenomena, for his international activities in geophysics.Kaplan also participated in efforts to launch the first Earth satellite.Kaplan was a member of the National Academy of Sciences, a fellow of the Institute of Aeronautical Sciences,chairman of the U.S. National Committee for the International Geophysical Year,the founder and first director of the Institute of Geophysics at the University of California (later known as the Institute of Geophysics and Planetary Physics),an aerospace adviser to Presidents Dwight D. Eisenhower and Richard M. Nixon,a recipient of the Smithsonian Institution's Hodgkins Medal in 1967,the head of the Air Force's Air We