Dr. Ernst Stuhlinger, one of the members of Wernher von Braun's inner circle and an invaluable resource to myself and Erika Lishock in writing our book The First Space Race, has died. A physicist who collaborated with James Van Allen on the first American satellite, Explorer 1, he helped develop the Jupiter C/Explorer design, especially the guidance system. When Explorer 1 lifted off on January 31, 1958, Stuhlinger had the critical job of studying DOVAP signals and other data to determine when the booster had arced over to the proper angle for him to manually ignite the upper states and put the satellite in orbit. Stuhlinger was with NASA for many years after the agency absorbed the von Braun team from the Army. He was one of the inventors of the ion propulsion concept now being actively used in deep-space exploration.
Farewell to a great contributor to spaceflight.