Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA
NASA Goddard Space Flight Center, Code 682, Greenbelt, MD 20771, USA; SSAI, c/o NASA GSFC Code 682, Greenbelt, MD 20771, USA
Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA
E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375, USA
E. O. Hulburt Center for Space Research, Naval Research Laboratory, Washington, DC 20375, USA
Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA
Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA
Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA
Space Sciences Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA
NASA Goddard Space Flight Center, Code 682, Greenbelt, MD 20771, USA
Observatoire de Paris, 5 Place J. Janssen, Meudon, 92195 France