The second man on the Moon reveals exclusively to All About Space how Apollo 12, not Apollo 11, could have been the first manned lunar landing.

The following is an excerpt from our exclusive interview with Buzz Aldrin in issue 11 of All About Space magazine, on sale now.

All About Space

Did you always know that Apollo 11 would be the first manned lunar landing mission?

Buzz Aldrin

“What had been happening in the evolution of Apollo was that Apollo 11, when it was assigned its crew, was potentially going to be the first landing mission. However, I’ve recently learned from the programme manager Hugh Davis that Lunar Excursion Module 5 [LEM 5, the Apollo 11 Eagle lunar lander], which was scheduled to fly on Apollo 11, was originally not qualified for landing. It was overweight.”

All About Space

What did that mean for the mission?

Buzz Aldrin

“It was overweight early in the programme, maybe around the time of Apollo 8, but a weight reduction programme was instituted by my good friend Hugh Davis and it resulted in an acceptable weight for LEM 5 so instead of the first landing mission going to be Apollo 12 in October 1969, with a different crew [Pete Conrad, Alan Bean and Richard Gordon], it now was backed up to Apollo 11 [in July 1969], giving us a couple more months before the end of the decade [to fulfill Kennedy’s objectives].”

All About Space

When did you find out about this major development?

Buzz Aldrin

“I want to emphasise that my understanding of the progression of Apollo until very recently had been that we would fly Apollo 8, 9, 10 and 11 as planned, and that would be the first lunar landing. We had a press conference after selection of a crew in January of 1969 and Neil Armstrong, Michael Collins and myself were billed as the first possible lunar landing mission. And it wasn’t until quite recently, within the last month, that I discovered that really, there was a period of time where the first landing was going to be Apollo 12 in October, and not Apollo 11 in July. I just don’t think very many people, besides myself, realise that. I think Hugh Davis was key to Apollo 11 being qualified to make the first landing attempt.”

All About Space

So you might not have been the first men on the Moon?

Buzz Aldrin

“Well originally it was scheduled for Apollo 11 to be the first lunar landing, then evidently without notifying the nation and the crew, it slipped to being Apollo 12 because of the overweight condition in Apollo 11’s original design. It needed to be light enough to land, so they kept kind of working on it and not disclosing until a final decision was made. And so history was gonna play out a different way. And that again had a major impact on my life and career, and Neil Armstrong’s career, if LEM 5 had remained too heavy to make a landing attempt.”

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