CV Roederer Professor of Physics Emeritus, Geophysical Institute and Department of Physics, University of Alaska Fairbanks (since 1993). Senior Adviser, The Abdus Salam International Centre for Theoretical Physics (1997-2003). Professor of Physics, Geophysical Institute and Department of Physics, University of Alaska Fairbanks (1977-1993). Chairman, United States Arctic Research Commission (presidential commission, 1987- 1991). Director, Geophysical Institute, University of Alaska Fairbanks, 1977-1986. Dean, College of Environmental Sciences, University of Alaska Fairbanks, 1979-1982. Chairman, Advisory Committee, Los Alamos National Laboratory, Division of  Earth and Space Sciences, 1985-1988. Vice Chairman, U.S. Arctic Research Commission, 1985-1987. Visiting Staff Member, Johns Hopkins University, Applied Physics Laboratory, 1987. Visiting Staff Member, Los Alamos National Laboratory, University of California, 1968-1981. Expert (consultant), Headquarters, National Aeronautics and Space Administration, 1974-1978. Visiting Professor, Stanford University, 1974. Professor and Senior Research Physicist, University of Denver, 1967-1977. Professor of Physics, University of Buenos Aires, 1959-1966. Director, National Cosmic Ray Center, National Council for Scientific and Technological Research, Buenos Aires, 1962-1966.