Celebrating the 45th anniversary of the first lunar landing, President Barack Obama on Tuesday recognized the "courage" of astronauts Neil Armstrong, Buzz Aldrin, and Michael Collins, who participated in the mission.
"It was a seminal moment not just in our country's history, but the history of all humankind," Obama said of the Apollo 11 mission.
The president welcomed to the White House Aldrin, Collins and Carol Armstrong, the widow of Neil Armstrong, who was the first man to walk on the Moon. He died in August 2012 at the age of 82.
"The men and women of NASA are building on that proud legacy by preparing for the next giant leap in human exploration - including the first visits of men and women to deep space, to an asteroid, and someday to the surface of Mars," Obama said.
The United States "is stronger today," Obama added, thanks to "the courage of Neil, Buzz, and Michael."
On July 20, 1969, Armstrong and Aldrin set foot on the Moon and planted an American flag, as they were watched by half a billion TV viewers.
Collins remained in the command module orbiting the Moon.
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