Buzz Aldrin: Where were you when I walked on the moon?

Associated Press

CAPE CANAVERAL, Fla.

On July 20, 1969, Buzz Aldrin was “out of town” when the world united and rejoiced in a way never seen before or since.

He and Neil Armstrong were on the moon.

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

Now, on this Apollo 11 milestone — just five years shy of the golden anniversary — Aldrin is asking everyone to remember where they were when he and Armstrong became the first humans to step onto another heavenly body, and to share their memories online.

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

Celebrities, public figures, and other astronauts and scientists are happily obliging with videos.

“What a day that was,” said actor Tom Hanks, sipping from an Apollo 11 commemorative cup. He starred in the 1995 film “Apollo 13,” another gripping moon story.

In all, 12 men explored the moon in six landings through 1972. But that first moonwalk, by Armstrong and Aldrin, is what clinched America’s place as space leader supreme after a string of crushing losses to the Soviet Union, which claimed title to first satellite, first spaceman, first spacewoman and first spacewalker.

It’s the first big anniversary of man’s first moon landing without Armstrong, whose “one small step ... one giant leap” immortalized the moment.

Armstrong, long known for his reticence, died in 2012 at age 82.

As Apollo 11’s commander, Armstrong was first out the lunar module, Eagle, onto the dusty surface of Tranquility Base. Aldrin followed.

Collins, now 83, the command module pilot who stayed behind in lunar orbit as the gatekeeper, also spent decades sidestepping the spotlight. He’s making an exception for the 45th anniversary — he plans to take part in a NASA ceremony at Kennedy Space Center on Monday.

That leaves Aldrin, 84, as the perennial spokesman for Apollo 11. He also will be at Monday’s ceremony.