Dr. Marshall is a project manager at the NASA Glenn Research Center in Cleveland, OH, where he is a part of the Exploration Systems Office. He has over 21 years experience in chemical propulsion research and test, and is a 2008 graduate of Penn State University, where he obtained his Ph.D. studying transverse mode combustion instabilities in oxygen/methane rockets. While at NASA, Dr. Marshall has focused on a number of chemical propulsion systems for in-space applications, including oxygen/methane engine development, additive manufacturing applications to rocket engine technology, micropropulsion systems for CubeSat applications, nuclear thermal propulsion ground test development efforts, and ionic liquid green propulsion development. He is formerly co-chair of the Green Propulsion Working Group, an NASA advisory working group focused in green propulsion research and development. He serves as the Glenn Research Center Project Manager for the Center's contributions to the Human Landing System. He was formerly Deputy Manager for Service module within the Crew & Service Module group of the Orion Program. Dr. Marshall is an Associate Fellow of AIAA, and is formerly a member of both the AIAA Liquid Propulsion Technical Committee (LPTC) and Honor & Awards Chair of the AIAA Northern Ohio Section