Steven R. Nagel, a veteran astronaut who flew four space shuttle flights on as many different orbiters, died Thursday after a long illness.
He was 67.
Nagel was an Air Force test pilot before becoming a NASA astronaut in 1979 and logging 723 hours in space.
He served as a mission specialist during a June 1985 Discovery flight and piloted the Challenger in October of the same year. He commanded his two final missions to space: An Atlantis flight in April 1991 and a 10-day jaunt on Columbia in April 1993.
"It will always be my honor to know Steve," Brian Kelly, director of flight operations, said in a NASA news release. "He blessed our lives in many ways. His humor, positive approach to life and constant smile is something we will all cherish. His service to our great nation and NASA is inspirational."
Nagel, who was born on Oct. 27, 1946, in Canton, Ill., earned a bachelor's degree in aerospace engineering from the University of Illinois in 1969 and a master's degree in mechanical engineering in 1978 from California State University at Fresno.
After retiring from the U.S. Air Force in 1995, Nagel immediately became a deputy director for Johnson Space Center's safety, reliability and quality assurance office. The next year, he moved to the aircraft operations division where he served as a research pilot, chief of aviation safety and deputy chief.
When Nagel retired from NASA in 2011, he joined the University of Missouri's College of Engineering where he taught in the department of mechanical & aerospace engineering. At the time of his death, he was listed as living in Columbia, Missouri.
One of Nagel's final Houston-area public appearances was in 2009, when he served as grand marshal of the Tomball Holiday Parade.
He is survived by his wife, Linda, and two daughters, Lauren and Whitney.
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