Dr. Roger Clark earned his Ph.D. in Planetary Science at MIT in 1980. Roger's expertise is in identifying and mapping minerals and other compounds on the Earth, other planets and their satellites using imaging spectroscopy. He develops laboratory, telescopic and spacecraft spectrometers and imaging spectrometers. He has published over 300 scientific papers, including papers on every planet in the Solar System. His research includes discoveries of the compositions of planetary and satellite surfaces and mapping the locations of minerals on the Earth and planets. In 2009 he discovered widespread water on the surface of the Moon. He also publishes on environmental issues on the Earth, such as ecosystems in Yellowstone, led the USGS environmental assessment of the World Trade Center Disaster and developed a new method for measuring the amount of oil on the ocean's surface and leading to the first quantitative assessment of the amount of oil on the ocean's surface in the 2010 Deepwater Horizon, Gulf of Mexico oil spill. Dr. Clark was a Senior scientist (ST) with the U. S. Geological Survey until October, 2014. There were less than 50 of these elite ST scientists in the USGS, several now retired. Before the USGS, he was an Associate Research Professor at the University of Hawaii. Dr. Clark is now a senior scientist with the Planetary Science Institute.