US astronaut John Young, who flew to the moon twice and commanded the first ever space shuttle mission, has died aged 87, Nasa said.
"Today, Nasa and the world have lost a pioneer," agency chief Robert Lightfoot said in a statement.
Young was the only person to have flown missions on the Gemini, Apollo and space shuttle programmes.
He also once famously smuggled a corned beef sandwich on to a space flight as a gift for a fellow astronaut.
Young retired in 2004 after a 42-year career. Nasa said he died on Friday following complications from pneumonia.
"John was one of that group of early space pioneers whose bravery and commitment sparked our nation's first great achievements in space," Mr Lightfoot said.
"But, not content with that, his hands-on contributions continued long after the last of his six space flights - a world record at the time of his retirement from the cockpit."
Born in San Francisco in 1930, Young gained a degree in aeronautical engineering at the Georgia Institute of Technology and then served in the US Navy as a test pilot.
He was picked as a Nasa astronaut in 1962 and first went into space in 1965 with the Gemini 3 mission.
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