1. Department of Physics; University of Idaho; Moscow Idaho USA
2. Natural Sciences Division; North Idaho College; Coeur d'Alene Idaho USA
3. Department of Geological Sciences; University of Idaho; Moscow Idaho USA
4. Now at ConocoPhillips Company; Houston Texas USA
5. NASA Goddard Space Flight Center; Greenbelt Maryland USA
6. Department of Geology; Brigham Young University; Provo Utah USA
7. Jet Propulsion Laboratory, California Institute of Technology; Pasadena California USA
8. Royal Observatory of Belgium; Brussels Belgium