1. Department of Earth, Atmospheric and Planetary Sciences; Massachusetts Institute of Technology; Cambridge Massachusetts USA
2. NASA Goddard Space Flight Center; Greenbelt Maryland USA
3. Center for Research and Exploration in Space Science and Technology; University of Maryland; Baltimore County Baltimore Maryland USA
4. Lamont-Doherty Earth Observatory; Columbia University; Palisades New York USA
5. Department of Terrestrial Magnetism; Carnegie Institution of Washington; Washington, District of Columbia USA