Astronaut John Young, who walked on the moon and was the first to fly into space six times, died Friday night at 87.
In a statement, acting NASA Administrator Robert Lightfoot said Young died from complications from pneumonia. He called Young NASA's "most experienced astronaut."
“Today, NASA and the world have lost a pioneer," Lightfoot said. "Astronaut John Young's storied career spanned three generations of spaceflight; we will stand on his shoulders as we look toward the next human frontier."
A former fighter pilot, Young started his career with NASA in 1962. His first flight as an astronaut came in March 1965 aboard the Gemini 3 with fellow astronaut Gus Grissom. He went to the moon in May 1969 aboard Apollo 10 and again in April 1972 on Apollo 16.
Young had gone into space as apart of the Gemini, Apollo and space shuttle programs, the only NASA astronaut to be a part of all three, Lightfoot said.
He had also served in the U.S. Navy and retired with a rank of captain. In 2004, he retired from NASA.
Former president George H.W. Bush called Young a "good friend" in a statement.
"To us, he represented the best in the American spirit — always looking forward, always reaching higher," Bush said.