Alfred Worden (Astronaut): Alfred Merrill "Al" Worden, is an American astronaut and engineer who was the Command Module Pilot for the Apollo 15 lunar mission in 1971. He is one of only 24 people to have flown to the Moon.
Scott Kelly (Astronaut): Scott Joseph Kelly is an engineer, retired American astronaut, and a retired U.S. Navy Captain. A veteran of four space flights, Kelly commanded the International Space Station on Expeditions 26, 45, and 46.
Chris Hadfield (Astronaut): Chris Austin Hadfield OC OOnt MSC CD is a retired Canadian astronaut who was the first Canadian to walk in space. An engineer and former Royal Canadian Air Force fighter pilot, Hadfield has flown two space shuttle missions and served as commander of the International Space Station.
Buzz Aldrin (Astronaut): Buzz Aldrin is an American engineer and former astronaut, and the second person to walk on the Moon. He was the lunar module pilot on Apollo 11, the first manned lunar landing in history. He set foot on the Moon at 03:15:16 on July 21, 1969, following mission commander Neil Armstrong. He is also a retired colonel in the United States Air Force and a Command Pilot.