1. Department of Physics Blackett Laboratory Imperial College London London UK
2. British Antarctic Survey Cambridge UK
3. GFZ German Research Centre for Geosciences Potsdam Germany
4. Department of Earth, Planetary, and Space Sciences University of California Los Angeles CA USA
5. Mullard Space Science Laboratory University College London Surrey UK
6. Department of Mathematics, Physics, and Electrical Engineering Northumbria University Newcastle Upon Tyne UK