WASHINGTON // When man first harnessed fire, no one recorded it. When the Wright Brothers showed that man could fly, only a handful of people witnessed it. But when Neil Armstrong took that first small step on the moon in July 1969, an entire globe watched it in grainy black-and-white from a quarter of a million miles away.
We saw it. We were part of it. He took that "giant leap for mankind" for us.
Although more than half of the world's population wasn't alive then, it was an event that changed and expanded the globe.
"It's a human achievement that will be remembered forever," said John Logsdon, professor emeritus of space policy at George Washington University in Washington, DC.
Those first steps were beamed to nearly every country around the world, thanks to a recently launched satellite and was truly the first global mass media event, said Mr Logsdon. An estimated 600 million people - 1 out of every 5 on the planet - watched it happen.
The most memorable historic events from the 20th century are likely to be the moon landing and the first atomic bomb, said Roger Launius, the space curator of the Smithsonian Institution.
"There is no way to overestimate that significance in human history and he is forever linked to that," he said of Armstrong, who died on Saturday at the age of 82.
Just as the voyage of Christopher Columbus split historic eras 500 years ago, so will Neil Armstrong and Apollo 11, said the historian Douglas Brinkley, a specialist in 20th-century history at Rice University in Houston, Texas.
"We may be living in the age of Armstrong," said Mr Brinkley, who conducted oral histories for Nasa, including sessions with Armstrong.
The late science fiction author Arthur C Clarke wrote that the Apollo 11 moon landing was "one of the great divides in human history; we are sundered from it forever by the moment when Neil Armstrong and Buzz Aldrin stepped out on to the Sea of Tranquility. Now history and fiction have become inexorably intertwined."
Since that day, there's been a common phrase: "If we can send a man to the moon, why can't we...?", with the blank filled with a task that seems easier. Armstrong's small step was a leap in confidence that told the world "if we can do this, we can do anything", said Howard McCurdy, a professor of space and public policy at American University and author of the book Space and the American Imagination.
"He took something that 20 years earlier was pure fantasy and turned it into reality, and if we could do that for space we could do it for anything," said Mr McCurdy.
The Apollo 11 moon landing was the finish line in a decade-long space race started by the Soviet Union, so the first steps on the moon being those of an American civilian had many meanings.
Getting there first showed American technological superiority, but Armstrong mentioned mankind - not Americans - demonstrating that this was a moment for the people of Earth, said Mr McCurdy.
Armstrong and Buzz Aldrin left a plaque on the moon that read: "Here men from the planet Earth first set foot upon the moon. July 1969 AD. We came in peace for all mankind." For all mankind. And that's how the world took it.
"The success for America [is a] success for every living man," said the Swahili-language newspaper Nguromo of Dar.
Armstrong and Aldrin also left a patch to commemorate the Nasa astronauts and Soviet cosmonauts who had died in pursuit of space.
"It was special and memorable but it was only instantaneous because there was work to do," Armstrong said this year.
The Cold War may have slightly muted the significance of the event at the time, but over the years the importance of the moon landing has only grown, said Mr Logsdon.
It has permeated into culture. It is in movies, television, books, songs - it was even Michael Jackson's signature dance step. That's probably because in some ways that moonwalk touched something hard-wired into humanity: the need to explore. For 25,000 years, humans have migrated and pushed into new places. Armstrong took it to new heights.
As John Glenn, the first American to orbit the Earth, noted, it was "the first time any human being set foot on a place other than Earth, and that's a pretty big step".