He remained there until 1979 and during that time bought a 310-acre farm near Lebanon, where he raised cattle and corn. He stayed out of public view, accepting few requests for interviews or speeches.
"He didn't give interviews, but he wasn't a strange person or hard to talk to," said Ron Huston, a colleague at the University of Cincinnati. "He just didn't like being a novelty."
Those who knew him said he enjoyed golfing with friends, was active in the local YMCA and frequently ate lunch at the same restaurant in Lebanon.
In 2000, when he agreed to announce the top 20 engineering achievements of the 20th century as voted by the National Academy of Engineering, Armstrong said there was one disappointment relating to his moonwalk.
"I can honestly say — and it's a big surprise to me — that I have never had a dream about being on the moon," he said.
From 1982 to 1992, Armstrong was chairman of Charlottesville, Va.-based Computing Technologies for Aviation Inc., a company that supplies computer information management systems for business aircraft.
He then became chairman of AIL Systems Inc., an electronic systems company in Deer Park, N.Y.
Armstrong married Carol Knight in 1999, and the couple lived in Indian Hill, a Cincinnati suburb. He had two adult sons from a previous marriage.
Armstrong's is the second death in a month of one of NASA's most visible, history-making astronauts. Sally Ride, the first American woman in space, died of pancreatic cancer on July 23 at age 61.
One of the NASA's closest astronaut friends was fellow Ohioan and Mercury astronaut Glenn, the first American to orbit the Earth.
Just prior to the 50th anniversary of Glenn's orbital flight this past February, Armstrong offered high praise to the elder astronaut and said that Glenn had told him many times how he wished he, too, had flown to the moon on Apollo 11. Glenn said it was his only regret.
Noted Armstrong in an email: "I am hoping I will be 'in his shoes' and have as much success in longevity as he has demonstrated." Glenn is 91.
At the Griffith Observatory in Los Angeles on Saturday, visitors held a minute of silence for Armstrong. For anyone else who wanted to remember him, his family's statement made a simple request:
"Honor his example of service, accomplishment and modesty, and the next time you walk outside on a clear night and see the moon smiling down at you, think of Neil Armstrong and give him a wink."
Borenstein reported from Washington. Associated Press writer Steve Peoples in New Hampshire and AP Science Writers Alicia Chang in Los Angeles and Marcia Dunn in Cape Canaveral, Fla., contributed to this report.
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