Elvis Presley's first national television appearance occurred on January 28, 1956, on CBS's Stage Show, hosted by the Dorsey Brothers. For this debut, the 21-year-old performed a medley of "Shake, Rattle and Roll" and "Flip, Flop and Fly," introducing his unique style to a national audience for the first time. Credit: CBS, Jackie Gleason Productions | History In Pictures

In November 1961, Enos became the first chimpanzee and the third hominid to orbit the Earth as part of the NASA Mercury-Atlas 5 mission. His successful two-orbit flight and safe recovery demonstrated that the spacecraft was ready for human passengers, paving the way for John Glenn’s historic flight months later. Credits: NASA, National Archives and Records Administration (NARA), Universal Newsreels | History In Pictures

A Warner Bros.-First National Picture (1946)