Institution: | Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT; Service d'Aéronomie du CNRS, BP 3, 91371 Verrieres-le-Buisson, France; Space Sciences Laboratory, University of California, Berkeley, CA 94720, USA; Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90089, USA; Department of Astronomy, University of Wisconsin, 475 N. Charter Street, Madison, WI 53706, USA |