During a news conference in Houston that same day, several NASA officials commented on the President's address. Associate Administrator Robert C. Seamans, Jr., stated that Kennedy's proposals came as no great surprise. He said that many "large areas" for cooperation exist, such as exchanges of scientific information and in space tracking, but emphasized that no cosmonauts would be flying in Apollo spacecraft. Deputy Associate Administrator George E. Mueller shared Seamans' views, comparing future U.S.-U.S.S.R. cooperation in space to joint explorations in Antarctica. Scientists from both nations work together, but "they get there in different ships." Just three days earlier, MSC Director Robert R. Gilruth had told the National Rocket Club that a joint American-Russian space flight - especially one to the moon - would present almost insuperable technological difficulties. "I tremble at the thought of the integration problems . . . ," he said. Gilruth cautioned his audience that he was speaking "not as an international politician," but as an engineer. The task of mating American and Russian spacecraft and launch vehicles would make such international cooperation "hard to do in a practical sort of way." And at the September 20 MSC news conference he added that such problems "are very difficult even when they (hardware components) are built by American contractors."