1. Lunar and Planetary Institute, USRA Houston Texas USA
2. Department of Earth and Planetary Science Birkbeck University of London London UK
3. Department of Earth Sciences Natural History Museum London UK
4. UCL/Birkbeck Centre for Planetary Sciences University College London London UK
5. School of Physical Sciences Open University Milton Keynes UK
6. Department of Earth Sciences University College London London UK
7. CNR—Istituto Scienze Polari Padua Italy
8. WiscSIMS Laboratory, Department of Geosciences University of Wisconsin‐Madison Madison Wisconsin USA
9. Department of Geosciences University of Massachusetts Amherst Amherst Massachusetts USA
10. SETI Institute Mountain View California USA
11. Department of Physics and Astronomy University of Khartoum Khartoum Sudan