1. The Johns Hopkins University Applied Physics Laboratory Laurel MD USA
2. Department of Physics and Astronomy University of Iowa Iowa City IA USA
3. Space Research Corporation Annapolis MD USA
4. NASA Goddard Space Flight Center Greenbelt MD USA
5. Laboratory for Atmospheric and Space Physics University of Colorado Boulder Boulder CO USA
6. Southwest Research Institute San Antonio TX USA
7. Jet Propulsion Laboratory Pasadena CA USA
8. Space Science Center University of New Hampshire Durham NH USA