Lt. Col. John E. Keator of the Warfare Systems School, USAF, yesterday expressed doubt that the United States can reach the moon before 1970 in his lecture sponsored by the Department of Air Science.

President Kennedy's target date for a moon flight coincides with an unusually intense period of solar flares or bursts of radiation, he pointed out, which would prove fatal to any space traveler. Twenty-five pounds of shielding per square foot could protect a voyager against the Van Allen radiation belts, he said, but adequate protection from flares would not be feasible because of the greater weight required.

Lt. Col G. T. Rogers also of the Air University, concluded the program in discussing the psychological problems of any future space voyager. The Air Force, he said, was making great progress in discovering how man would react to long periods of isolation.