Simplify the following text for a Grade 12 native English-speaking person.
Original: Francis Richard `` Dick '' Scobee ( May 19 , 1939 - January 28 , 1986 ) was an American astronaut who was killed commanding the Space Shuttle Challenger , which suffered catastrophic booster failure during launch of the STS-51-L mission .
Simplified: Francis Richard `` Dick '' Scobee ( May 19 , 1939 - January 28 , 1986 ) was an American astronaut who was the lieutenant colonel of Space Shuttle Challenger when it blew up and killed him and six other crew members .