1. Department of AstronomyUniversity of Maryland College Park MD USA
2. NASA Goddard Space Flight Centre Code 674 Greenbelt MD USA
3. Department of PhysicsUniversity of Alberta Edmonton Alberta Canada
4. Department of Space and Climate Physics, Mullard Space Science LaboratoryUniversity College London London UK
5. Department of MeteorologyUniversity of Reading Reading UK
6. Laboratory for Atmospheric and Space PhysicsUniversity of Colorado Boulder Boulder CO USA