National Geographic : 1959 Feb
iiV than that of the Air Force. The Army sought escape velocity for l'ioneer III- enough sheer force to elude the clutch of earth-moon gravity. But the Air Force probe required a more critical and refined velocity, since missilemen wanted the payload to orbit the moon. l'ioner III journeyed through space with only a few payload instruments: two radia tion monitoring tubes, a radio transmitter, and a Iphotoelectric sensing device. shaped like a pistol. Scientists had hoped the moon's bright face would actuate the photocells and signal that fact back to earth. Once tested. the cells would be used in some later moon probe as a trigger device for a television camera. For its probe the Army used a modified Jupiter missile as the first stage, topped by three solid-fuel stages. Once again Luis Slarden and I watched a blinding, pulsing column of flame throw heavenward another challenge to the moon. At take-off only an effort of will kept our eves to the view finders of cameras. One's tendency is to forget everything but the sorcery of the moment. PAINTING EY MEL HUNTER(L) N S.