Joseph Robert Guinn was born in Houston, Texas. He attended the University of Texas at Austin and obtained B.S. and M.S. degrees in the field of Aerospace Engineering. He is currently employed at the California Institute of Technology's Jet Propulsion Laboratory in Pasadena, California. He has been involved with tracking and navigation of planetary and Earth orbiting spacecraft. Most recently, he supervises the Inner Planet Navigation group that primarily provides development and operations support to NASA’s Mars Exploration Program. He also has worked on GPS based precision orbit determination for the TOPEX/Poseidon ocean topography experiment and on autonomous navigation for the New Millennium Program’s Earth Orbiter-1 mission.