Laboratoire de Planétologie de Grenoble, Grenoble, France

Laboratoire de Planétologie de Grenoble, Grenoble, France

Plasma and Space Physics Group, Department of Physics, University of Oslo, Norway

Department of Arctic Geophysics, University Centre in Svalbard (UNIS), Longyearbyen, Norway

Department of Arctic Geophysics, University Centre in Svalbard (UNIS), Longyearbyen, Norway

Solar-Terrestrial Environment Laboratory, Nagoya University, Japan

The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA

Space Vehicles Directorate, Air Force Research Laboratory, Hanscom AFB, MA, USA

now at: National Geophysical Data Center, NOAA, Boulder, CO, USA