05/31/2007 07:00:00

Early Rocketeer Homer Stewart Dies

PASADENA, Calif.—Homer Stewart, an early pioneer of rocket research who helped develop Explorer I, America's first satellite, died Saturday, May 26, at his home in Altadena, California. He was 91.

A native of Dubuque, Iowa, Stewart came to the California Institute of Technology for graduate study in 1936 and became interested in the early pioneering rocket research that was being carried out at the time by a small group of Caltech engineers and scientists, chief among them Theodore von Kármán. Stewart, von Kármán, and others began testing rockets in a rugged foothill area of the San Gabriel Mountains about five miles northeast of the Pasadena campus, thereby forming the nucleus of the research group that would evolve into the Jet Propulsion Laboratory.

In 1938, Stewart joined the Caltech faculty from 1938, teaching both aeronautics and meteorology; but for many years he divided his time between his faculty duties and research at JPL. As chief of the research analysis section, he participated in many rocket projects, including the WAC Corporal, the Corporal, the Sergeant, and the Jupiter C. He was chief of JPL's liquid propulsion systems division when JPL and the Army Ballistic Missile Agency (now the Marshall Space Flight Center) developed and launched Explorer I.

His research interests included rocket exhaust velocity requirements for maintaining the exact trajectories of spacecraft. He also conducted research in wind-driven energy, using his knowledge of fluid flow to construct with von Kármán a turbine in the mountains of Vermont in the late 1930s. The the machine generated up to a megawatt of power and operated through World War II in cooperation with a local electrical company. The project was abandoned after the war, in part because of the easy availability of cheap fossil-fuel energy.

Stewart earned his bachelor's degree at the University of Minnesota in 1936 and his doctorate in aeronautics at Caltech in 1940. He served continuously on the Caltech faculty from 1938 until his retirement in 1980.

He is survived by two daughters, Barbara Mogel of Chesapeake Beach, Maryland, and Kay Stewart of San Diego; a son, Dr. Robert J. Stewart of Burien, Washington; and two grandchildren.

Written by Robert Tindol