Complex sentence: He became Professor of Aerospace Engineering in 1980, serving in that capacity until 1999, when he retired and was named Professor Emeritus, he also served as an affiliate member of the History Department at UMD.
Split into simpler sentences: He became Professor of Aerospace Engineering in 1980, serving in that capacity until 1999, when he retired and was named Professor Emeritus. He also served as an affiliate member of the History Department at UMD.