Ronald Greeley has a PhD in geology, and is Professor of Geology and Meteorite Studies at Arizona State University. He has worked in lunar and planetary science since 1967. Recent spacecraft involvement includes participation in the Galileo mission to Jupiter and the Mars Pathfinder flights. Current planetary mission involvement includes science team membership on the Mars Express Orbiter.
Raymond Batson has a degree in geology from the University of Colorado, and has spent his 35-year career with the United States Geological Survey. Batson served as co-investigator or team member on the science teams of most NASA planetary missions, including the Apollo lunar lander missions, the Mariner Mars and Venus/Mercury mapping missions, the Viking 1 and 2 Mars mapping missions, the Voyager missions to the outer planets, and the Magellan Venus radar mapping mission.