Michael Douglas Griffin (born November 1, 1949 in Aberdeen, Maryland) is an American physicist and aerospace engineer. He served as Administrator of NASA, the U.S. space agency, from April 13, 2005, to January 20, 2009. As NASA Administrator Griffin oversaw such areas as the future of human spaceflight, the fate of the Hubble telescope and NASA's role in understanding climate change. In April 2009 Griffin, who has an academic background, was named eminent scholar and a professor of mechanical and aerospace engineering at the University of Alabama in Huntsville.