“When we can demonstrate that we can take off horizontally and put something into orbit, then we can begin to talk about increasing the amount of payload. But to say, 'I'm going to do that and put people into orbit' is a real leap.”

American astronaut and engineer of the Apollo era, Buzz Aldrin is best known as the second person to walk on the Moon during the Apollo 11 mission in 1969. His career spans pioneering spaceflight, engineering, and advocacy for space exploration, as well as later work as an author and public speaker on science and human achievement.