Seven men in the history of humanity stand apart from the rest of us. These are the Apollo command module pilots who spent time alone in orbit around the Moon, while their colleagues walked on the lunar surface. When they were on the far side of the Moon, these astronauts were completely out of contact, and further from Earth, than anyone had ever been before. Or has ever been since.

Only five of these people are still alive and, when I meet him, Apollo 15 command module pilot Al Worden still looks every bit the veteran astronaut. Even in the unlikely surroundings of a crowded restaurant in Yorkshire, in northern England, this former test pilot stands out – an alpha male holding court, surrounded by a group of admirers eagerly hanging on his every word.

Worden flew to the Moon in July 1971, alongside commander Dave Scott and lunar module pilot Jim Irwin. During his time alone on the command module he entered the record books as the "most isolated human being" ever - at times his companions being 3,600km (2,235 miles) away on the lunar surface.

Like the other Apollo astronauts I’ve met Worden would rather talk about the mission and its achievements, than himself. As the first of the so-called “J” class missions, Apollo 15 is widely accepted as the most scientifically rigorous of the Apollo programme. Nevertheless, as we sit down in a quiet corner of the hotel bar, with proposals out there for a return to the Moon and missions to Mars, I’m keen to learn about the human experience of being so far from home:

Do you feel that command module pilots get overlooked by history – you had what was perceived as the less glamorous job?

It’s kind of funny, everybody’s focussed on those who land on the Moon but their function is to pick up a rock. They’re just out gathering rocks and they bring all those rocks back and they get analysed. In terms of the science, you gather a lot more science from lunar orbit than you can on the surface. I photographed, for example, about 25% of the lunar surface – the first time that had been done. I mapped about that same amount. That’s a lot of data to come back. In fact, I guess they’re still looking at it.

I’m interested in what was going through your mind as the lunar lander separated from the command module and you see it getting smaller and smaller in the window as it passes out of sight and descends towards the Moon. What goes through your mind when that’s happening?

First off, you wish them luck: “I hope you land okay!” The second thought is: “gee I’m glad they’ve gone because I’ve got this place all to myself.” And so I had three wonderful days in a spacecraft all by myself.

Wasn’t it lonely?

There’s a thing about being alone and there’s a thing about being lonely, and they’re two different things. I was alone but I was not lonely. My background was as a fighter pilot in the airforce, then as a test pilot – and that was mostly in fighter airplanes – so I was very used to being by myself. I thoroughly enjoyed it. I didn’t have to talk to Dave and Jim any more, except once they came around [when the orbiting command module was above the landing site) and I said “hi”. On the backside of the Moon, I didn’t even have to talk to Houston and that was the best part of the flight.

You were a quarter of a million miles away from home though.

Yes, you’re a long way away but the thing that most impressed me about being in lunar orbit – particularly the times when I was by myself – was that every time I came round the backside of the Moon, I got to a window where I could watch the Earthrise and that was phenomenal. And in addition to that, I got to look at the universe out there with a very different perspective and a very different way than anyone had before.

What I found was that the number of stars was just so immense. In fact I couldn’t pick up individual stars, it was like a sheet of light. I found that fascinating because it changed my ideas about how we think about the Universe.

There are billions of stars out there – the Milky Way galaxy that we’re in contains billions of stars, not just a few. And there are billions of galaxies out there. So what does that tell you about the Universe? That tells you we just don’t think big enough. To my mind that’s the whole purpose of the space programme, to figure out what that’s all about.

Did that not make you feel even smaller and even more alone?

Oh yeah, you want to feel insignificant? Go behind the Moon sometime. That’ll make you really feel that you’re nothing!

I’m intrigued that you said you preferred being out of contact with Houston, why was that?

I didn’t need someone yammering in my ear. I had a lot of work to do. I had a lot of things I was trying to accomplish. I kind of say that in a joking way, because if anything serious were to come up then I’d certainly want them to contact me. But if everything was going well, I didn’t need to talk to them and I could concentrate on the science I was doing.

How busy were you? I imagine a lot of your thinking about the Earth and the Universe was done after the mission?

That’s a funny thing, when you’re out there observing all this and doing all this remote sensing, and the photographing and the-this and the-that, you don’t really have time to think much about it. You put it in a memory bank and when you get back that you think about all that. I worked 20 hours a day and I’d get three or four hours of sleep a night. So you really don’t have the luxury of the time to sit and look out of the window and think “oh gosh I can ponder on the universe out there and philosophise about what’s there.”

What about music – what was your mix tape for the Moon?

We had little cassette players that we could use during the flight. I was, and still am, an absolute Beatles fan and I love their music. I also carried some Elton John, some John Denver and the Blue Danube Waltz [from the movie 2001, a Space Odyssey].

You are one of only seven people who have been isolated, in orbit around the Moon [the others are the command module pilots of Apollo 10, 11, 12, 14, 16 and 17 and only Apollo 15, 16 and 17 pilots spent three days alone in lunar orbit]. Are there lessons that astronauts in the future can learn, if and when we return to the Moon or go onto Mars?

I think there probably are, although we all had different experiences. The lesson I got was don’t get too friendly with your crew. With the long periods of time you spend with the other two, I found that I was more tuned to doing the job I had to do than I was with interfacing with them. We really worked well together professionally but we were not particularly great friends and I think that was a benefit.

How does that work then? It’s hardly a nine to five job when you can go home at the end of the today, away from your work colleagues?

That’s why you need to maintain a distance between people. If you get to a point in a flight where it’s time to take a rest, not do anything for a while, you need to be comfortable that you can enjoy the solitude without having to feel you have to talk to everybody.

I guess we all expect you to be chums, are you saying that’s not necessarily the case?

Apollo 12 they were always buddies – Pete Conrad treated his crew like brothers. If you saw one, you saw all three because they were always together. We were the opposite of that, we trained together but we didn’t socialise a lot together and I think that made us a more effective crew.

Your colleagues Dave Scott and Jim Irwin left footprints on the Moon – which will be there for millions of years. Will you have left anything behind as a memorial to your mission? Your urine maybe?

It could be, we actually made urine dumps when we were in lunar orbit. What we had to do was we’d open the valve and flush it all out, then make a trajectory change so we got out of the way. It could still be there. However, the Moon doesn’t have enough gravity to retain particles in orbit – that’s why there’s no atmosphere. I suspect anything we’ve dumped has disappeared by now – my guess is there’s nothing left.

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