NAU Planetary Scientist Mark Loeffler (IMAGE) Northern Arizona University Caption NAU planetary scientist Mark Loeffler works with students in his PEAXS (Processes, Environments, and Astrochemistry on Extraterrestrial Surfaces) Research Laboratory. Credit Photo courtesy of Northern Arizona University Usage Restrictions Credit as shown above License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.