Paul Geissler is a research geologist at the Astrogeology Science Center of the US Geological Survey. His expertise is in image processing and remote sensing, and he is interested in geological processes across the solar system that are active today. He has written or coauthored more than 90 peer reviewed publications on a wide variety of topics, ranging from impact cratering on asteroids to the colorful aurorae on Jupiter’s moon Io. He participated in the Galileo mission to Jupiter, studying volcanism on Io and tectonics on Europa, and also participated in the Cassini mission as it flew by the Jupiter system. More recently, he has studied active processes on Mars as a member of the Mars Exploration Rovers Athena Science Team and the Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment (HiRISE) Science Team. His studies of Mars are focused on eolian processes, including the motion of sand dunes, the activity of dust devils, and the effects of regional and global dust storms that alter the appearance of the surface of Mars over time. Dr. Geissler received his PhD in planetary science (1992) from the University of Arizona, his MS in geophysics (1987) from the University of Melbourne, and his BSc in physics and geophysics (1983) from the University of Tasmania.