Institution: | 1. NASA, Ames Research Center, Moffett Field, CA 94035, U.S.A.;2. Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309, U.S.A.;3. Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, U.S.A.;4. Institute of Applied Mathematics, U.S.S.R. Academy of Sciences, Moscow 125047, U.S.S.R. |