"I've been asked oh, so many times over the last years: 'How does it feel to be the end, how does it feel to be the tail of the dog, the last one over the fence?' I got on my soapbox after we came back, but in January of '73 I was at Kennedy [Space Center, Florida] for homecoming, and I said: 'I've been tired of being called the end. Apollo 17 is not the end. It's just the beginning of a whole new era in the history of mankind.'"

Eugene Cernan, the last man to have walked on the moon, died on Monday 16th January. In memory of the astronaut, we went back to an oral history conducted in 2007, 35 years after the final Moon landing, for the NASA Johnson Space Center Oral History Project in Houston, Texas to consider the man’s lunar legacy in his own words.

A US Navy Captain, Cernan flew three times in space, twice to the Moon. The second American to walk in space, he was the last human to leave his footprints on the Moon. In May 1969, he was the lunar module pilot of Apollo 10 and in 1972, he commanded the last human mission to the Moon with Apollo 17.  Below, we parsed the oral history to gather some of his thoughts on that legacy.

Eugene Cernan on Piloting

“There’s no way I’m going to go all the way to the Moon, particularly for a second time, and let a computer land me on the Moon.

“The arrogance of a pilot, particularly naval aviators, is too great to allow that to happen. Nobody ever landed on the Moon other than with their own two hands and brain and eyeballs and whatever.

“Computer-assisted, yes. Got a lot of information. We got help from a lot of sources. But you’re looking for landing radar. You’re looking to maintain the communications. You’re on your back. You’ve got to roll over. You’ve got to go face up. A lot of things happen very quickly.

“As I say a very dynamic, exciting 14 minutes of your life, maybe 15. At 7,000 feet you pitch over, so for the first time you can really see the landing site where you’re going to land.”

Eugene Cernan on Landing

“That’s where you experience the most quiet moment a human being can experience in his lifetime. There’s no vibration. There’s no noise. The ground quit talking. Your partner is mesmerized. He can’t say anything. The dust is gone.

“It’s a realization, a reality, all of a sudden you have just landed in another world on another body out there [somewhere in the] universe, and what you are seeing is being seen by human beings, human eyes, for the first time. Where you are no human beings have ever been before.”

Eugene Cernan  on Preparation

“So we prepared to get out. Had to prepare all our backpacks and everything. Then I started down the ladder. But the first step on the Moon had already been taken by Neil. So this was not the first step on the Moon. However, it was my first step. Let me tell you, it truly was a first step for me.

“It was important historically to me personally because well selfishly, because it was my step. I’d come close in Apollo 10, and now I was actually on the Moon, now I was actually going to step on the surface of the Moon.”

Eugene Cernan on First Steps

Images courtesy of NASA

“So when I stepped on the surface I realized I was really there, and that for the first time, I’m stepping on another body in this universe. You can climb the highest mountain or walk the depths of the deepest ocean on Planet Earth but you’re still on Planet Earth. Now after all that zero-G traveling for three days and my other flights, I’m standing and touching something hard, something I can feel, and it’s not Earth. (Pounding fist) That came home to me very very clearly. I’m living, truly living in another world at this point in time.

“There have been people who want to believe in the fantasy or the conspiracy, whatever, that it was all done in Hollywood, we never really walked on the Moon. Well, if they want to have missed one of the greatest adventures in the history of mankind, that’s their choice.

“But once my footsteps were on the surface of the Moon, nobody, but nobody, could ever take, and to this day can take those footsteps away from me. Like my daughter’s initials I put into the Moon during that three days we were there. Someone said, “How long will they be there?” I said, “Forever, however long forever is.” I’m not sure we, any of us, understand that.”

Viruses like HIV may have followed us from the sea to the land

New research has suggested the family of viruses that includes HIV survived the evolutionary transition from sea to land, which would make them several hundred million years older than previously thought.

The study by scientists at Oxford University found that retroviruses – including the HIV virus responsible for the AIDS pandemic – are almost half a billion years old. But until recently, it was thought that retroviruses were only 100 million years in age.

“Our new research shows that retroviruses are at least 450 million years old, if not older, and that they must have originated together with, if not before, their vertebrate hosts in the early Paleozoic era,” says study author Dr Aris Katzourakis, from Oxford University’s Department of Zoology.

“Furthermore, they would have been present in our vertebrate ancestors prior to the colonisation of land and have accompanied their hosts throughout this transition from sea to land, all the way up until the present day.”

Image courtesy of Oxford University

In order to date retroviruses, the researchers overcame one of the key limitations in studying the deep evolutionary history of viruses: their rapid evolution.

To combat this, a new model was used that allowed for the reconstruction of the viruses’ distant past in addition to their recent history.

Using this model, the researchers were able to speculate on the present-day activity of retroviruses as well as the adaptations that have been developed to combat them.

“Our inferred date of the origins of retroviruses coincides with the origins of adaptive immunity, and thus it is likely that retroviruses have played an important role in the emergence of this key tool in vertebrate antiviral defence,” says Katzourakis.

The Oxford scientists’ next step will be to consider the adaptations that vertebrates have developed to combat viruses and the corresponding viral countermeasures, as well as discerning viruses like HIV’s exact origin.

“As we understand the nature of the interaction between viruses and host immunity, we will be better placed to intervene in this delicately balanced arms race in order to develop novel treatments and interventions,” says Katzourakis.

“And as we build a clearer picture of the origins of the diverse groups of viruses that infect us today, we should come closer to unravelling the mystery of their ultimate origins.”

The paper ‘Marine origin of retroviruses in the early Palaeozoic Era’ is published in Nature Communications.