Apr. 30, 1962 - Lieut. Col. John H. Glenn Jr. and Maj. Gherman S. Titov, the Soviet astronaut now visiting this country, will make a joint television appearance on Sunday to discuss space exploration. NBC said the program would be taped on Friday in Washington for a telecast on Sunday from 6:30 to 7:30 p.m. NBC also said that after the astronauts had compared experiences and exchanged views, they would answer questions from a studio audience. Simultaneous translation from Russian into English and English into Russian will be provided, the network said. Major Titov circled the earth 17 times last August. Colonel Glenn’s 3-orbit flight occurred on Feb. 20.