Michael John Smith (April 30, 1945 – January 28, 1986), (Capt USN) was an American engineer and astronaut. He served as the pilot of the Space Shuttle "Challenger" when it was destroyed during the STS-51-L mission, when it broke up 73 seconds into the flight, and at an altitude of 48,000 feet (14.6 km), killing all 7 crew members. Smith's voice was the last one heard on the "Challenger" voice recorder. He was a Master of Science who held a degree in Aeronautical Engineering.