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Telescopes and space missions

Telescopes and space missions

Microbes and the Moon

23 Jul 2019
Taken from the July 2019 issue of Physics World.

As he watched the film First Man, a particular scene towards the end caught the attention of physicist Michael Hill-King. In this article (originally published in Lateral Thoughts, Physics World’s regular column of humorous and offbeat essays, puzzles, crosswords, quizzes and comics, which appears on the back page of the print edition), he finds out why the Apollo 11 astronauts were quarantined on their return to Earth

Nixon Apollo 11 quarantine
(Courtesy: NASA)

After watching the 2018 film First Man – which depicts eight years in the life of astronaut Neil Armstrong leading up to the legendary Apollo 11 mission – my wife, who is a microbiologist, remarked to me that she hadn’t realized that the astronauts were quarantined. She was referring to the final scene of the film, wherein Armstrong and Buzz Aldrin are shown behind a large glass wall, depicting the pair in quarantine, as they watch a replay of John F Kennedy’s famous speech.

My immediate response to my wife was that what I found more surprising is that only two of the three astronauts appeared in the quarantine scenes. Michael Collins was nowhere to be seen.

His absence led us to reflect on the ways in which biological material could have been transferred to the astronauts and how any contamination on either Armstrong or Aldrin could easily have been passed to Collins during the three-to-four days they spent together in a tiny capsule on its way back to planet Earth. What were the possible sources of contamination? In any case, why wasn’t Collins depicted as also being quarantined? They breathed the same air in the capsule and there was proximity of their spacesuits.

After digging into these questions some more, I found half a dozen reviews of the film that mentioned the quarantine. They confirmed my observation that Aldrin and Armstrong were both quarantined, but none of them mentioned the missing Collins, nor asked why he wasn’t there. This puzzled me, and I decided to find out what happened to all three astronauts in reality.

I eventually came across the Smithsonian National Air and Space Museum, whose archives include a photograph depicting the newly returned space-travelling trio, all three of whom were indeed quarantined upon their return. The Smithsonian website captions the above photograph: “President Richard M Nixon was in the central Pacific recovery area to welcome the Apollo 11 astronauts aboard the USS Hornet, prime recovery ship for the historic Apollo 11 lunar landing mission. Already confined to the Mobile Quarantine Facility are (left to right) Neil A Armstrong, commander; Michael Collins, command module pilot; and Edwin E Aldrin Jr, lunar module pilot.” The First Man depiction is therefore an oversight.

We no longer need to worry about the risk of lunar microbes, which might have been brought back to Earth by Collins, causing a threat for the past half-century. But why were the astronauts quarantined? What were the possible sources of nuclear, biological or chemical contamination? It’s hard to remember that our own knowledge of the Moon is relatively recent. In the early days of lunar exploration, we didn’t know that the Moon was sterile. We didn’t know whether there would be water on the surface or some form of biological life. We were simply driven by a desire for exploration.

To deal with the unknown, the “Extra-Terrestrial Exposure Law” was enacted in 1969 to guard against “the remote possibility that they are harbouring unknown lunar organisms that might endanger life on Earth”. This regulation remained in force in the US until 1977, following data obtained from many quarantines, when it was concluded that “There is no hazard to man, animals or plants in the lunar material.”

Nowadays, astronauts are quarantined before voyages to reduce the chance of an infection developing that would affect their ability to perform their duties effectively. However, there is also a discussion to be had about whether the Moon itself should be quarantined, to avoid biological contamination by objects from Earth. First Man depicted the deliberate contamination of the Moon, when Armstrong left behind a bracelet, in memory of his late daughter. I don’t know if that’s a true story, but it is well-known that during later Apollo missions, some of the astronauts played golf on the Moon under relatively low gravity – I doubt that the golf balls were recovered and returned to Earth.

Three decades after the first lunar landings, the Moon became the final resting place for the geologist and planetary scientist Gene Shoemaker, when some of his ashes were carried there by the Lunar Prospector space probe in 1999. He is best known for co-discovering the Shoemaker–Levy 9 comet, together with his wife Carolyn S Shoemaker and David H Levy. I am not sure how Shoemaker got this privilege, but to date, he is the only person whose ashes have been buried on a celestial body that is not the Earth.

Perhaps the lesson to learn is that, occasionally, popular media help us look at our science in a new way

We are constrained to live our lives on Earth and look up at the Moon on a regular basis, so it’s no surprise that we have a natural fascination with our nearest neighbour. Perhaps the lesson to learn is that, occasionally, popular media help us look at our science in a new way. Sometimes, as we are busy protecting ourselves from the obvious, we may not realize the threats we ourselves pose. It’s not so much that we need fear extraterrestrial lifeforms – at least those that are locally based – but rather the impact of humans, which now reaches beyond the confines of our immediate home.

  • Readers are invited to submit their own Lateral Thoughts. Articles should be 900–950 words, and can be e-mailed to pwld@ioppublishing.org
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