1. Space Science Division, NASA Ames Research Center, Moffett Field, California
2. Department of Chemistry, University of Florida and Foundation for Applied Molecular Evolution, Gainesville, Florida
3. Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, D.C
4. Department of Chemistry and Biochemistry, University of California, Santa Cruz, California
5. Institute of Marine and Coastal Sciences and Department of Geology, Rutgers University, New Brunswick, New Jersey
6. Department of Geological Science, Arizona State University, Tempe, Arizona
7. Department of Biology, Pennsylvania State University, University Park, Pennsylvania
8. Laboratory for Atmospheric and Space Physics and Department of Geological Sciences, University of Colorado, Boulder, Colorado
9. Department of Organismic and Evolutionary Biology at Harvard University, Cambridge, Massachusetts