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During of the six lunar landings, the so-called Dusty Dozen valiantly fought their enemy. They trampled their boots on the outside and then squeezed the garbage bags around their legs to prevent dust from spreading. They attacked it with damp rags, hairbrushes and a low vacuum cleaner, which Pete Conrad of Apollo 12 called "a complete farce". (He ended up undressing and shoved his blackened suit into a pocket.) Cernan, on his return from his last moonwalk, swore, "I'm not going to do much more dust after I leave here. Never. In the end, NASA could not find a foolproof solution. Years after John Young had commanded Apollo 16, he still believed that "dust is the number one concern for the return to the moon".
Now, with national space agencies and private companies about to do so, Apollo logbooks are again relevant. In January, China laid its Chang-e-4 probe on the far side of the moon, the last step towards building a lunar research center. Two months later, the Japanese aerospace agency announced its partnership with Toyota to design a six-wheeled lunar rover by 2029. Around the same time, Vice President Mike Pence announced his intention to put American boots on the moon by 2024. According to NASA Administrator Jim Bridenstine, the goal is "to act sustainably. Stay. With landers, robots and rovers – and humans. "India and Russia also have planned missions. Then there are private companies like Moon Express, whose Harvest Moon expedition will prospect for water, minerals, and other resources to exploit. Which raises a crucial question: what to do with this problematic dust? An Australian physicist named Brian O & Brien might have the answer.
O & # 39; Brien has become almost by accident the supreme authority of the Earth on the moon dust. In 1964, five years before Apollo 11 landed in the Sea of Tranquility, he was a young, lean and precocious professor of space science from Rice University in Houston, specializing in the study of radiation. It was at the beginning of the Apollo formation, when astronauts were taking intensive courses on all kinds of subjects: vector calculus, antenna theory, human nose physiology. O & # 39; Brien's job was to teach them the Van Allen Belts, two regions of intense radiation that surround the planet like a pair of inflatable pool tubes. He remembers the Apollo class of 1964, which included Gene Cernan and Buzz Aldrin, as the most "disciplined and alert" student cohort of his life.
In the run-up to the launch of Apollo 11, O & Brien persuaded NASA to include a little something extra in the payload. It was a small box, the size of a thick soap bar, whose main function was to measure the accumulation of dust on the surface of the moon. O & # 39; Brien describes it as a device "hitchhiking and deliciously minimalist". He sketched it on the back of his coaster during a Los Angeles-Houston flight and refined the design on a cocktail napkin. Named DDE (Dust Detector), this was perhaps the least impressive component of the Apollo 11 science pack; NASA has not even bothered to mention it in press releases. But it worked out pretty well that the agency included modified versions of the original DDE on all subsequent Apollo flights. Four of them are still up there and hold to date the record for the longest experiences on the moon.
For many years, it was thought that the data that the first DDEs had sent back to Earth were missing or lost. Since its surprise rediscovery in 2006, actors in the inner circle of space activities have slowly begun to realize that the unpretentious detectors of O. Brien have much more to tell us about the moon dust than anyone else could have Imagine, with the exception of course of course O & # 39; Brien himself. Now 85 years old and still living in Perth, he has been waiting for half a century for the chance to share with the world what he knows about one of the most confusing substances in the world. solar system.
O & # 39; Brien has always had an affinity for extreme environments. As a teenager, he began caving and found himself stuck in the depths of the Australian Yarrangobilly Caves for 79 hours. The experience was traumatic: his lamp ran out of fuel and, according to a contemporary newspaper, he only heard "bats above his head and the feel of their tiny skeletons under his boots," But that was not the case. Do not discourage him from speleology. A few years later, while exploring a crystal cave, he met his future wife, Avril Searle.
At age 23, O & # 39; Brien had completed his Ph.D. in Physics at the University of Sydney and had been named Associate Chief Physician of the Commonwealth Antarctic Division. He was assigned to the icebreaker Magga Dan and found himself staring marvelously at the waving aurora in the reds, purples, and greens across the polar sky. It was in 1958, a year after the launch of Sputnik by the Russians and the same year, NASA was founded. O & # 39; Brien began dreaming of putting a satellite into orbit to study how protons and energized electrons gave birth to southern lights. He had his chance the following year, when James Van Allen, discoverer of Van Allen's belts, found him a job at the University of Iowa. O & # 39; Brien and a few students built a satellite in five months. Other launches followed and in 1963, O. Brien was seen offering a position at the new space science department of Rice University.
Shortly after moving to Houston, O. Brien received a call from NASA. The agency hoped to hire him as an astronaut instructor, but also invited him to submit a proposal for a scientific experiment on the moon. He suggested a device to measure the energy spectrum of charged particles as they rained on the lunar surface. Out of a total of 90 applications, he is one of seven who received the green light. NASA told him that, as a matter of principle, the experiment should include a dust cover, essentially a sophisticated plastic band. At this point, nobody knew how much the dust of the moon would be boring, but O. Brien felt that if the agency was using to install dust caps, it should also include a dust. detector.
In the beginning, NASA and its private subcontractors hesitated. They thought that it would be too difficult to build a detector light enough to meet mission specifications and simple enough that it does not take as much time and attention from astronauts. On the moon, distractions could be deadly. O & # 39; Brien thought their resistance was "fucked up" and, with the help of this cocktail napkin, devised a motive to calm their worries. It consisted of three tiny solar cells mounted on a box painted white to reflect the sunlight. As the dust settled on the cells, their output power dropped, providing a clear record of accumulation over time. O & # 39; Brien added some temperature sensors, bringing the total weight of the experience to 10 ounces. As the DDE was so small, it could be attached to the seismometer that Aldrin and Neil Armstrong were installing to measure the moon tremors. After hearing all this, NASA gave in: the DDE could go to the moon. Once there, he would transmit his data to the seismometer, whose antenna would transmit the readings to the Earth. They would be stored on tape reels for further analysis.
O & # 39; Brien, April and their three children returned to Sydney in 1968. So he arranged for the tapes to be shipped to him. He does not remember very well now where he was in the morning of late July 1969, when the Apollo 11 lunar module sits on the moon. He thinks he listened to the radio between interviews with various Australian media outlets. Still, he remembers very well the moment Aldrin said that the module "was raising dust" by the time he arrived, as well as Armstrong 's observation, just before getting off the l'. scale, that the surface was "almost like a powder". With a spike in excitement, O 'Brien realized that his DDE could very well prove his worth.
In the end, the seismometer overheated soon after the departure of Apollo 11 from the Moon. (Before ceasing to operate, says O & # 39; Brien, he recorded the astronauts' footsteps on the scale and "flickering of the flowing fuel.") But the DDE persevered and quickly revealed the harm that the dust could cause. Almost immediately after takeoff of the lunar module, two of the three solar cells of the detector recorded a sudden drop in their yield, one of them by 18%. This was accompanied by a hint of temperature. For O & # 39; Brien, there was only one logical explanation: the DDE was covered with dust that, like blackout blinds, prevented light from entering and heating. It seemed obvious to him that the seismometer had suffered the same fate.
If NASA hoped to continue using its lunar instruments during its future Apollo missions, O. Brien concluded, it would be necessary to study thoroughly the problem of dust spraying. That August, he proudly wrote to an Australian colleague that "the DDE may have really won his trip!", But his American counterparts, including the Manned Spacecraft Center's technicians, were not as enthusiastic. He thinks that some of them were less interested in seeking scientific knowledge than in the appalling goal of landing Americans on the moon. In the end, the seismometer stopped accepting the controls of the mission control and the entire experiment – including DDE – was closed after 21 days.
In October, NASA released its preliminary scientific report on Apollo 11. It largely dismissed O & # 39; Drien's explanation regarding DDE readings, blaming calibration errors for low production unexpectedly solar cells. (This was written in a chapter co-authored by O 'Brien, who says however that he "was in deep disagreement" with the conclusions and that he never gave permission to include his name.) O & # 39; Brien again tried to plead his case in court. Journal of Atmospheric Physics, using one of the first Australian supercomputers, SILLIAC, to analyze and plot data on endless paper ribbons. But the article had a dull sound and was hardly cited by other researchers in the decades that followed.
O & # 39; Brien was forced to admit his defeat in the first round of Monday's moon wars. He changed careers and became the first head of the Environmental Protection Authority of Western Australia. The post was based in Perth, and when Avril made the three-day train trip from Sydney, she brought the children and the 172 DDE data reels with her. O & # 39; Brien asked a colleague from a local university to store the tapes. And so, for forty years or so, it 's there that they stayed.
Brian O'Brien: Australian physicist, astronaut instructor, Moondust Maven.
JOE MCKENDRY
Apollo 11 Dust Detector Experience: The white painted housing has three solar cells mounted on the top and a temperature-sensitive glass plate screwed to the front.
Alyssa Foote
After the final Apollo landing in 1972, NASA has almost lost interest in the moon. There were space stations to assemble, exotic planets to explore, and limited funding. Then, in 2004, President George W. Bush announced what would become the Constellation program. There would be new powerful rockets, redesigned crew pods and more spacious lunar modules – "Apollo under steroids", as one NASA administrator said. Part of the plan was to establish a permanent "foot" on the moon, which meant a renewed interest in the logistics of regular landings and long-term settlements.
It was something that Philip Metzger, a global scientist, had been interested in for a while. Metzger was the co-founder of Swamp Works, a sort of technological incubator at NASA's Kennedy Space Center, which creates practical solutions to the challenges of work and life in places beyond the Earth. As part of his doctoral dissertation, he had conducted research on ways to prevent exhaust gases from creating dust and damaging lunar infrastructures, and he had been traveling for decades. Studies of rock and soil samples reported by Apollo astronauts. He even had four rare vials of real moon dust in his lab. Over the years, he had perfected a lunar geology lesson for his team.
It looked almost like this: the regolith, a layer of rocky material overlying the primordial bedrock, contains dust, gravel and mixed pebbles. It is thought to be about 15 feet thick in the plains and 30 feet thick in the uplands. For all intents and purposes, the moon does not have an atmosphere or magnetic field, so the highest layer of the regolith is likely to degrade. It is constantly bombarded by cosmic rays and the solar wind, which means that the dust can be electrostatically charged, like a balloon rubbed on the hair. It also receives a constant amount of micrometeoroids.
When micrometeorides strike, they create miniature shock waves in the ground that melt and vaporize some of them. The molten soil splashes, but then freezes again, forming tiny pieces of glass. Metzger explains that these pieces have a "crazy shape", that they are shredded, sharp and very frictionnal. Unlike the Earth, where wind and water would mitigate them, they will remain so forever. (When Aldrin and Armstrong planted an American flag near their landing site, they struggled to get the pole into the regolitan, blocked by its high glass content. "It took us both to put it in place, and it was almost a disaster in public relations, "Aldrin remembers years later.) Thanks to the constant pounding of micrometeorides, the soil is extraordinarily thin, making it sticky. Metzger compares it to the "fine hairs of the gecko's feet that allow him to climb the walls".
Metzger would complete his geology lesson with a sobering summary of health risks. Our body usually coughs or sneezes with daily irritants. But anything smaller than 10 microns, about one seventh of the diameter of a human hair, tends to remain trapped in our lungs. In the soil sample reported by Apollo 17, some of the dust is less than 2 microns, as fine as flour. Unsurprisingly, astronauts suffered from what Jack Schmitt, who flew on board Apollo 17, called "lunar hay fever" (as noted by Australian scholar Alice Gorman in her book Dr. Space Junk vs. l & # 39; universe, the fear of dust contamination spread to West Africa, where people started talking about a new severe form of conjunctivitis called Apollo's disease.)
For all of Metzger's expertise in the world, there was an enigma that still held him. Some parts of a former spacecraft called Surveyor 3 were in his laboratory at the Kennedy Space Center. Between 1966 and 1968, five Surveyor probes were laid on the moon, providing irrefutable evidence that the regolith was firm enough to land and relax. no fear that astronauts will collapse in the shifting sands of the moon. (The photograph of Aldrin's footprint in the ground – one of the most famous images of human history – was in fact taken to allow the study the "bearing strength of the lunar surface".) The final resting place of Surveyor 3 was at a walking distance from the Apollo 12 landing, and the astronauts had been instructed to report some parts to the house for examination. One of them, Alan Bean, noted at the time that the bright white surface of the probe had turned to tan after two and a half years on the moon.
Previous researchers had assumed that this was due to the damage caused by solar radiation, but in 2011, Metzger and his colleagues proved that it was "an ultrafine dust embedded in the microtexture of the painting". The biggest question was how the dust had gotten there. . As Surveyor 3 landed in the virtual void of the moon, the exhaust gases from its engine should have pushed dust a way of the spacecraft. The Metzger team could not explain it.
At this point, the Constellation program had been canceled. The new rockets were out of budget and were late, and the Obama administration decided it was better to leave this puzzle to the private sector. NASA should be concerned with thinner and more science-based missions. Metzger had already begun to hear a number of companies seeking to be photographed by the moon. Many had participated in the Google Sponsored Lunar XPrize Contest, which promised $ 20 million to the first team to land on a satellite, move it a short distance and transmit images to the Earth. (No one has ever managed to get there.) Increasingly worried that all future traffic and dust he projected might be landing at Apollo's landing sites, Metzger helped develop a set of official guidelines on lunar heritage of NASA, recommending a one kilometer exclusion zone around them. (This is an arbitrary substitution figure, he says, because of the way moon dust behaves when disturbed, there may indeed be "no safe distance". )
A few years later, Metzger took an early retirement from NASA and joined the faculty of planetary sciences at the University of Central Florida. His latest project at Swamp Works was to develop strategies for dust dust mitigation, including magnets, reusable dust filters, artificial electrostatic charges to repel dust and drop surfaces, and "Air showers" or "chopsticks" to explode. suit. Even with immediate plans for an American lunar base at the table, Metzger said, he had become "consensual conviction" while it was at NASA that "the biggest challenge for lunar operation is dust".
In 2015, long after abandoning the mystery resolution of Surveyor 3 's dust deposits, Metzger heard of a series of articles recently published by Brian O' Brien. They contained a really remarkable theory about moon dust. While reading, Metzger realized that it was the first acceptable explanation that he had found to solve his riddle. And it was surprisingly based on the data from the original DDE tapes.
The imprint of Buzz Aldrin in the lunar soil.
NASA
O & # 39; Brien came back in the game of the moon, as he had entered – by chance. In 2006, when he was seventy years old, a friend mentioned reading an article on a NASA website about the sad state of some Apollo tape archives. O & # 39; Brien decided to find the reels that he had asked a colleague to stock for him all these decades ago. They found themselves in a room under the bleachers of a conference room of Curtin University's Physics Department in Perth. They were covered with dust (what else?), But they were there, each one of them, each containing about 2,500 feet of tape. The only problem was that they were in such an outdated format that the data was beyond the reach of O. Brien. He sent an email to NASA proposing to repatriate the tapes, but the agency politely refused.
A local radio reporter heard rumors about the discovery and posted an article. The news was relayed to Guy Holmes, an American physicist who had been living in Perth for years and founded SpectrumData, a company that specializes in digitizing large volumes of data from older tape formats. Holmes phoned O & # 39; Brien to offer his help for free. He said that he would stock the tapes in a special climate-controlled box until they could find the right machine to decode them. O & # 39; Brien gratefully accepted.
Even if Holmes was successful in his research, O 'Brien was not sure to ever find funding – from NASA or anyone else – to reanalyze the data. But he felt that he had one last chance to set the record straight on moondust and put an end to his frustrations early in his career. So he set to work revisiting his old SILLIAC analyzes and printouts, determined to publish a peer-reviewed article. He appeared in 2009, nearly 40 years after his first article, Moondust.
The story of O. Brien – his dramatic discovery of cassettes at an advanced stage of his life, his forgotten role in the Apollo program – drew much attention from the media. And it was impossible not to fall under the influence of the moon dust once he began to explain how bizarre it was.
O & # 39; Brien had gone back and looked at the DDE data that flew on Apollo 12. This detector was different from its predecessor: it had a horizontal solar cell at the top and two vertical cells at the sides. They were covered in dust as the astronauts walked on the moonlaces and then blowed in part as the lunar module took off. Curiously, however, one of the vertical cells became completely clean during the night. O & # 39; Brien explained that the electrostatic charge of dust – the main source of its tackiness – changes over the long lunar day. When the sun is high and the UV radiation is at its maximum, the dust is extremely charged and therefore very sticky. When the sun goes down, the dust seems to lose some of its adhesive force. If Pete Conrad had been on the moon again at sunset, he might have had a better chance of vacuuming his suit.
Less than two months after the publication of the article, O. Brien had been appointed Adjunct Professor at the University of Western Australia. He was invited to speak at the second annual Lunar Science Forum, held at NASA's Ames Research Center in California. The room was so full at the presentation that people found themselves in the hallway. The youngest followers of the moon had the same disbelief of never hearing of O. Brien or his DDEs. "After that, things started to bubble up," he says.
In early 2010, Holmes himself had a breakthrough: he had located an old IBM 729 Mark 5 tape drive in the Australian Computer Museum's warehouse. It was the size of a two-door refrigerator and was in a deplorable state, but the museum agreed to lend it to him. A group of SpectrumData employees donated their time to fix it. The strips were carefully heated to remove all traces of moisture, then unrolled at very low speed. Holmes says that he was very moved during this rescue process, aware of its historical importance and the confidence that O & Brien had placed in him. Eventually, the team was able to decode and extract most of the data. O & # 39; Brien was, let's just say once, over the moon. Monique Hollick, an undergraduate student, now a Space Systems Engineer for the Australian Department of Defense, is registered to help analyze the resuscitated data. It took them many years. In 2015, they were ready to unveil a new, even stranger theory on Monday's moon.
O & # 39; Brien had already explained how the Apollo 12 DDE had become clean; What he had not explained, is how, in the days that followed the astronauts' departure, the dust resumed. The hypothesis of Hollick and himself was that after the astronauts left for their homecoming, leaving the DDE on the spot to broadcast his readings, the sun went down for about two weeks on the ground. When he climbed back, he covered the "collateral dust" they had raised – more than 2 tons in total – from ultraviolet rays. This caused a positive charge of the dust particles. They began to "mobilize and move," says O. Brien, as a "swirling ground fog." Repulsed by each other and by the surface of the moon, they have levity. This created a small dust storm high enough to reach the DDE. The next time the sun has risen, the same thing happened, and the next, and the next. Each time, the storm has become a little smaller, until there is no collateral dust left to feed it.
It's still a somewhat controversial theory. Schmitt, the geologic astronaut who flew Apollo 17, is not entirely convinced because most of the rocks he saw on the moon were dust free. "If fine dust levitated and redeposited with any lateral movement," he wrote, "I would not expect the rocky surfaces to be clean." In his own correspondence with Schmitt, O 'Brien suggested that these rocks had lost their dusty coating as the sun's angles changed.
Debates are in progress. Other researchers have pleaded for a dust cloud extending over tens or even hundreds of kilometers above the surface of the moon, although the Lunar explorer NASA's Atmosphere and Dust Environment, launched in 2013, found little evidence of this. And there are also other fanciful speculations, such as the idea that Moondust, in its undisturbed state, can be stored in porous and fragile structures called fairy castles. «Nous ne le saurons vraiment pas avant d'y aller», déclare Metzger. Il se sent cependant assez confiant que O'Brien a raison et que sa théorie résout le mystère de Surveyor 3 une fois pour toutes. Toute personne planifiant une mission lunaire, dit-il, devrait s’attendre à ce que des tempêtes de poussière lévitent à chaque lever de soleil autour de tout avant-poste très actif et de collants divers, le jour de la lune.
Les pays et les entreprises se bousculant pour s'implanter dans les sites les plus recherchés de la Lune – principalement les pôles lunaires, où la glace d'eau est censée être abondante – la vie pourrait y évoluer rapidement dans un gâchis poussiéreux et chaotique, propice aux conflits humains. Le groupe de travail de La Haye sur la gouvernance des ressources spatiales internationales a déjà commencé à rédiger des recommandations sur les «zones de sécurité» et les «droits de priorité» de la Lune. Ils devraient peut-être inclure une clause relative à la gestion interne.
Accroché à la Le mur du bureau du garage d’O'Brien à Perth est une photo dédicacée de la classe des astronautes Apollo de 1964. Buzz Aldrin et Gene Cernan sourient depuis le bas du tableau, semblant chouettes, bien qu’un peu fanés, en costumes et cravates. À côté du portrait de groupe se trouve une photo d'O'Brien avec Cernan, lors de la visite de Cernan à Perth en 2016, l'année précédant son décès. «Nous avons tous deux une apparence différente lorsque je lui ai fait la leçon», a déclaré O'Brien lorsque je me suis arrêté chez lui un chaud après-midi en février. J'ai demandé de quoi ils avaient parlé. «Moondust», répondit-il avec un sourire.
O'Brien se préparait pour un voyage au Texas, où il devait participer à une conférence de la NASA intitulée Microsymposium 60: Attendez-vous sur la lune pour rester. Il ferait le voyage seul; son épouse bien-aimée est décédée en 2017 et Holmes, qui l'avait accompagné lors d'une récente visite à Pékin, n'a pas réussi. O'Brien s'inquiétait de la manière dont il pourrait se débarrasser de ses bas de compression après le vol, mais il semblait insensible à l'idée de se présenter devant une foule de 200 personnes, y compris des représentants des neuf sociétés américaines récemment autorisées par la NASA. livrer des charges utiles sur la lune. Il a laissé entendre qu'il discutait avec plusieurs d'entre eux et a déclaré, d'une manière un peu énigmatique: «J'attends beaucoup plus de détecteurs de poussière."
Sur les étagères du bureau d’O'Brien, des souvenirs de l’espace dignes d’un geek-out majeur ont été confondus sans cérémonie. J'ai inspecté des modèles grandeur nature de ses divers DDE, avec des plaques apposées décrivant la mission Apollo sur laquelle ils avaient volé. O'Brien était heureux de me laisser jouer avec des modèles brillants de l'atterrisseur chinois Chang'e-3 et du rover Yutu sur la table basse, à condition que je mette d'abord des gants blancs. Ils lui ont été remis à Beijing par l'Académie chinoise des technologies spatiales, qui a pris contact après avoir suggéré que l'immobilisation inexpliquée de Yutu en 2014, après son premier lever de soleil lunaire, était une tempête de poussière. équiper le rover d'un détecteur de poussière. Il semblerait que Chang'e-3 ait effectué certaines mesures de poussière, que les Chinois ont confidentiellement communiquées à O'Brien; tout ce qu'il peut dire, c'est qu'il est «stimulé» par les résultats et espère qu'ils seront bientôt publiés.
Quelques jours après son retour du Texas, O'Brien l'a appelé pour lui demander comment s'était passée la conférence. Moondust est définitivement en train de faire son chemin dans l'air du temps, a-t-il déclaré avec plaisir. En 2009, lors de son premier entretien avec la communauté de la recherche lunaire, il a déclaré: «Je ne connaissais personne et personne ne me connaissait.» Cette fois-ci, presque tout le monde le connaissait. Il a admis que, tout en arpentant les longs et interminables corridors d’aéroports et de complexes de conférences étranges, il se sentait déjà bien dans sa vieillesse. «Mais quand je suis sorti du microsymposium et plusieurs semaines après, je me suis senti jeune à nouveau», a-t-il déclaré.
Ceridwen Dovey est un écrivain basé à Sydney. Elle est l'auteur des livres Blood Kin, Seuls les animaux, Dans le jardin des fugitifs, and Sur J. M. Coetzee: Écrivains sur écrivains.
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