Neil Armstrong (1930-2012) was an American astronaut, naval aviator, test pilot, and aeronautical engineer, best known as the first person to walk on the Moon.[1][2][4] Born on August 5, 1930, in Wapakoneta, Ohio, he earned a bachelor's degree in aeronautical engineering from Purdue University in 1955 after serving as a U.S. Navy pilot during the Korean War, where he flew 78 combat missions.[2][6][7][9] Armstrong began his civilian career as a research pilot for the National Advisory Committee for Aeronautics (NACA), predecessor to NASA, testing aircraft like the X-15 rocket plane, reaching speeds of Mach 5.74 (nearly 4,000 mph) and altitudes over 200,000 feet.[1][3][6][7] Selected in NASA's second astronaut group in 1962 as the first civilian astronaut, he commanded Gemini 8 in March 1966, achieving the first successful docking of two spacecraft in orbit with David Scott, though a thruster malfunction forced an emergency abort that he skillfully resolved.[1][2][3][4][8] His pinnacle achievement came as commander of Apollo 11 in July 1969, alongside Michael Collins and Buzz Aldrin. On July 20, Armstrong piloted the Lunar Module Eagle to a safe landing in the Sea of Tranquility, then stepped onto the lunar surface at 10:56 p.m. EDT, uttering, "That's one small step for [a] man, one giant leap for mankind." He and Aldrin spent over two hours exploring, collecting samples, and deploying experiments during the historic first manned Moon mission.[3][4][5][6] Post-NASA, Armstrong taught aerospace engineering at the University of Cincinnati, served on corporate boards, and led the 1970 investigation into NASA's Apollo 13 near-disaster. He lived privately until his death on August 25, 2012, from complications following heart surgery.[4] Armstrong's legacy endures as a symbol of human exploration, inspiring ongoing lunar programs like NASA's Artemis and private space ventures.[2][7]