This group of prominent experts included retired astronaut Neil Armstrong, then-active astronaut Sally Ride, and physicist Richard Feynman. PHYSICIST TURNED DETECTIVE: Richard Feynman played a key role in both the Manhattan Project and the investigation into the Challenger tragedy. “I believe that has some significance for our problem,” he said at a February 1986 hearing of the Challenger commission. For more than two years after the Challenger explosion, NASA put a pause on sending astronauts into space as they redesigned the space shuttle. But in February 2003, Space Shuttle Columbia broke apart when reentering Earth’s atmosphere.