Steven R. Nagel, a former astronaut who flew on four space shuttle flights, has died after a long illness. He was 67.
NASA said in a news release that Nagel died Thursday. Longtime friend Ed Reinholtz said Nagel died of cancer in Columbia, Missouri.
Nagel was a test pilot for the Air Force before becoming an astronaut in 1979.
NASA said he was a mission specialist during a June 1985 Discovery flight and the pilot aboard the Challenger in October 1985. He was commander on his last two missions—an Atlantis flight in April 1991 and a 10-day trip on Columbia in April 1993.
Nagel later worked as deputy director and deputy chief in two separate offices at Houston's Johnson Space Center.
Nagel retired from NASA in 2011.
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