 It might have been small consolation that Soviet planetary probe efforts during this time were little more successful, but all of their failures were kept secret, so the Soviets did not have to answer to their public about the waste of tax money on failed space missions.The successful launch of Mariner 2 on August 27 momentarily blunted criticism of NASA and Jet Propulsion Laboratory and also seemed to verify the soundness of the Ranger design.Meanwhile, JPL engineers were still trying to figure out what had caused the computer failure on Ranger 4, which had occurred during a period when the probe was out of range of ground tracking.