On July 20, 1969, Buzz Aldrin was “out of town” when the world rejoiced in a way never seen before or since. He and Neil Armstrong were on the moon.

They missed the celebration 45 years ago. So did Michael Collins, orbiting solo around the moon in the mother ship.

On this Apollo 11 milestone, Aldrin is asking everyone to share where they were when he and Armstrong became the first humans to step onto the moon.

Too young? You can share how the moonwalkers inspired you.

Celebrities, public figures and other astronauts are happily sending videos.

Buzz Aldrin, above, and fellow astronaut Neil Armstrong took a U.S. flag with them to the moon 45 years ago. (NASA/Agence France-Presse via Getty Images)

“What a day that was,” said actor Tom Hanks, who starred in the 1995 film “Apollo 13,” another gripping moon story.

“Going to space is a big deal. Walking on the moon is, literally, walking on the moon,” said singer-songwriter Pharrell Williams, born four years afterward.

In all, 12 men explored the moon in six landings through 1972. But that first moonwalk is what clinched America’s place as space leader after the Soviet Union claimed the first satellite, first spaceman, first spacewoman and first spacewalker.

It’s the first big anniversary without Armstrong, who died in 2012 at age 82. Collins, now 83, usually avoids the spotlight. That leaves Aldrin, 84, as the spokesman for Apollo 11.

“The whole world celebrated our moon landing. But we missed the whole thing because we were out of town. So now I invite you to share with me — and the world — your story or your family’s story of where you were on July 20th, 1969.”

To share, go to www.youtube.com/Apollo45. (Always ask a parent before going online.)

— Associated Press