1. Space Research Corporation, Annapolis, MD 21403, USA.
2. NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
3. Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, Rome, 00133, Italy.
4. Southwest Research Institute, San Antonio, TX 78238, USA.
5. Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA.
6. Institut d’Astrophysique et de Geophysique, Universite de Liege, Liege, B-4000 Belgium.
7. University of Leicester, Leicester, LE1 7RH, UK.
8. University of Iowa, Iowa City, IA 52242, USA.
9. National Space Institute, Technical University of Denmark, Kongens Lyngby, 2800, Denmark.
10. Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109, USA.
11. Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723, USA.
12. Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA.
13. Department of Atmospheric and Oceanic Sciences, University of California–Los Angeles, Los Angeles, CA 90095, USA.