Earthlings lucky enough to have televisions witnessed the event firsthand, watching transfixed as Neil Armstrong slowly descended the ladder from the Apollo 11 spacecraft and set foot onto the fine-grained silt that passes for soil there.
"It's one small step for [a] man, one giant leap for mankind," said Armstrong after stepping onto the lunar surface.
It remains a moving experience to this day.
The anniversary comes just one day after confirmation that an engine pulled up from the ocean floor is indeed a piece of that legendary mission. Amazon.com founder and CEO Jeff Bezos, whose exploration firm located the debris in March, announced on his blog on July 19 that it was one of the F-1 engines from the Saturn V rocket that helped Apollo 11 escape Mother Earth's gravity. NASA confirmed the discoveryin a separate statement.
In the intervening decades since that "small step," numerous ideas have been floated about how to get back to the moon again, and what to do once we get there. NASA wants to mine an ice-filled crater for water. (Related: Water Rights on the Moon? NASA Wants What’s in That Crater)
Almost lost in all the science is the sacredness of such a journey. Although American Indians were not directly involved in the mission, an eagle clutching an olive branch in the name of peace was its emblem.
And it is a little-known fact that just before stepping out of the spacecraft, astronaut Edwin "Buzz" Aldrin celebrated a private communion to commemorate the enormity of having actually ventured into the heavens, Time reports.
"Inside the lunar module, just hours before stepping onto the moon for the first time, Aldrin radioed Houston Space Center Mission Control. He asked for a few moments of silence 'to invite each person listening in, wherever and whomever they may be, to pause for a moment and contemplate the events of the past few hours, and to give thanks in his or her own way,' " Time.com said in a July 20, 2013 story.
"In that moment of silence that followed, Aldrin silently read a passage from the book of John that he had written out on a 3×5 card: 'I am the vine, you are the branches. Whoever remains in me, and I in him, will bear much fruit; for you can do nothing without me,' " Time said, noting that this was not broadcast and that Armstrong did not take part. Then, taking out bread, wine and a miniature chalice (given to him by his church) from his personal allowance pouch, Aldrin poured the wine and watched it curl along the sides of the cup in gravity one-sixth that of Earth as he contemplated that the first liquid poured on the moon, and the first food eaten, were entwined in sacred ceremony.
Thus regardless of the religion invoked, ceremony played a role in this most momentous of human milestones.
Several astronauts returning from space, moon walk or no, have attested to the sacredness and sense of awe engendered by such a journey. (Related: The World's Best View: What Seeing Earth From Outer Space Can Teach Us)
But the spirit of both exploration and humility that he and the Apollo 11 mission embodied lives on.