Arizona State University professor Mark Robinson was a 10-year-old growing up in Tennessee when he watched history being made with the first moon walk on July 20, 1969.
"It’s not a once-in-a-lifetime thing. It's a once-in-an-ever thing," he said, reflecting just before Wednesday's 47th anniversary of the historic event.
Now Robinson views the landing site through a much more powerful lens.
He oversees cameras on the Lunar Reconnaissance Orbiter, an unmanned NASA spacecraft that has been circling the moon since 2009.
To date, the three cameras aboard have returned more than 1.2 million photos, including the highest-resolution images yet of the Apollo 11 landing site taken about 15 miles above the surface.
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The photos show the faint foot paths made by American astronauts Neil Armstrong and Edwin "Buzz" Aldrin after they made history by becoming the first humans to land on another celestial body.
The photos also show a portion of the lunar landing spacecraft that was left behind when they returned to the main spacecraft.
The American flag planted by the astronauts isn't visible in the Apollo photos. That's likely because, Aldrin said, the flag blew over from the rocket blast when astronauts left the surface. But in 2012, NASA announced the orbiter's cameras spotted five flags from other Apollo missions. NASA released the Apollo 11 photos, along with images showing other mission landing sites.
Apollo 11 differed from the previous NASA moon missions, which conducted science experiments, Robinson said. Apollo 11's main goal was to show that the United States could land on the moon, plant the American flag and return home safely,
MORE: See how The Republic covered the event
On that day, Armstrong uttered the now-famous words "the Eagle has landed" to announce that the lunar landing module, named Eagle, had successfully touched down at 4:17 p.m. Eastern time.
Armstrong told NASA officials that landing was his biggest concern because of all the unknowns.
"There were just a thousand things to worry about," he said.
More than half a billion people watched Armstrong later on television, shortly before 11 p.m. Eastern time, as he climbed down the ladder and uttered the now-iconic phase, "That's one small step for man, one giant leap for mankind."
Armstrong and Aldrin spent 21 hours, 36 minutes on the moon before lifting off in the lunar module and returning to join fellow astronaut Michael Collins in the main spacecraft.
The Apollo program included multiple launches to the moon in the late 1960s and early 1970s.
A total of 12 men would walk on the moon. The "Last Man on the Moon" was Eugene Cernan, commander of the Apollo 17 mission in 1972. Before he left the lunar surface, he uttered these words:
"We leave as we came and, God willing, as we shall return, with peace, and hope for all mankind."