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People often ask, "How are we close to sending humans to Mars" and this is not surprising considering the optimistic presentations of Elon Musk and others. However, Mars is too far to send humans at this stage. As Canadian astronaut and former ISS commander Chris Hadfield said, "I think that eventually we will live on the moon for a generation before arriving at MarsWhat we need to know now, it is "We are close to sending humans to the moon."
It is not important to be able to send the mass of a spaceship with humans to Mars. And whether it's a human or 100 humans, there is little difference in it, it's not the main problem we're facing right now, except to the extent that it helps return to the Moon and indirectly with our first steps towards interplanetary travel. We could have sent a dead astronaut to Mars decades ago. The challenge is to send a live astronaut. And it's much more than sending the mass of humans + food + help to life, water, etc.
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What we need is experience. It's a minimum of 500 days but usually a two-year trip to Mars and back. Until now, we have sent humans around the moon and we have sent two astronauts to the lunar surface for three days at a time, thanks to the technology of the 1960s-1970s that we no longer . We have not even been able to reactivate the Saturn V and Apollo Moon hardware because the skills needed to make these components disappear. Gross as they were by modern standards, we could not make any safe working copies today.
At present, we do not have a safe way to send a human to the moon. And Apollo built a lunar mission step by step. We can skip the first pieces of Gemini, we have a lot of experience in shuttles to LEO. Except – only in the TMA Soyuz. This is already difficult enough. SpaceX and Boeing are not yet ready to send their first test flights with humans into space. Virgin Galactica or Blue Origin also do not plan to make sub-orbital hops.
Part of the problem is security. It is not so much that we are no longer able to take such risks. It is especially the fact that the Soyuz TMA is such a reliable spacecraft that it makes little sense to fly human beings in space until it is at least as safe as the Soyuz TMA. Because, unlike unmanned cargo, safety is paramount for humans. Even astronauts and test pilots, even if they are willing to take risks, take risks managed. They are not reckless. Indeed, they pay more attention to risk management and keeping them as low as possible, precisely because of their job as test pilots. Even today, many NASA astronauts began as test pilots.
If an astronaut dies in a Boeing or SpaceX mission that would have survived in a TMA Soyuz, how would we be after that? It would be a major blow. Especially if the inevitable investigation revealed that the accident was preventable.
So we have to go back to orbit first, the equivalent of Gemini missions, but much safer because we expect LEO trips to be reasonably safe. Then we have to send humans around the moon like Apollo 8. We have to test any material probably in LEO. We must test a lunar lander. Once we have it all together, we can go back to the moon. This is not a trivial thing to accomplish, even today. Nobody can do it right now.
Once we have humans on the Moon, they can then return to Earth in 2 days. When they are at LEO, they can come back in a few hours. This is a significant difference. Someone in critical condition after an accident – so the difference between a few hours and two days can easily be life or death for a medical evacuation. And space missions are dangerous and we could have accidents on the Moon that would force astronauts to return to Earth.
It's not just that. It is also the support of life. Life Support components on the ISS have failed many times, but this is only a minor problem because of the multiple redundancy and replenishment of the Earth. Space suits also fail and need to be repaired and eventually replaced. And they send several tons of equipment to the ISS every few months. It will not work as an interplanetary flight model. Indeed, it will be much less practical on the Moon.
For interplanetary flight to be practical – well – we can use the ISS-type system for up to about two years by taking a lot of supplies. But this must be very very reliable. If we have a failure of life support, multiple failures, the journey from Earth to Mars – instead of coming back in a few days, as for Apollo 13, the moment equivalent to Apollo 13 means that they have to hold on for two years before their return. Beyond about two years, we need better recycling than the ISS to keep the weight of life within practical limits. The BIOS-3 system based on aquaponics, aeroponics and the burning of plant residues should allow very long missions, even decades or more, without replenishment, but is not yet tested in the space. The MELLiSA system, based on composting residues, would also carry out operations on the ISS on long-duration space flights.
Any system that produces all the food that astronauts need while growing it, keeps them automatically fed with oxygen, the growing plants absorbing CO2 as astronauts expire by eating the previous generation of crops and producing oxygen at the same time. its place. , through the magic of photosynthesis. Algae can also provide oxygen, much more efficiently with a small volume of algae and bright tubes, so that light penetrates deeply into the solution. Unfortunately, they do not provide carbohydrates and do not produce the full range of amino acids. But are very robust with not much to be wrong. As long as there are still some algae cells, sterilize the system, reintroduce the algae and it will soon be operational again (try to do it in case of failure of a mechanical system!).
The natural place to test this is on the moon. It could be tested anywhere, including in LEO, but the Moon makes a lot more sense as astronauts have a reason to be. It is largely unexplored. Its area is greater than that of Africa. It's like a new unknown and unexplored continent. In the low gravity, there may be caves several kilometers in diameter, empty lava tubes – and there is evidence that some caves extend over 100 km. Certainly lots of holes in the caves, lunar "skylights".
There could be platinum ore deposits around the Aitken Basin, splashed by the core of an old impactor. There are cold spots as cold as liquid nitrogen at the poles and we now know that there is ice there, in crystalline form (not just water related to the rocks ). The most optimistic estimates are millions of tons. Do not see it in total darkness from the craters to the poles that have not seen sunlight for billions of years. Near them are the "PEL" or "Peaks of Eternal Light" – I think better called "PEALS", or Peaks of Eternal (Almost) Light as they have "winters" with occasional dark periods of a few days but for most of the year, sunlight is constant and temperatures are almost constant throughout the year, which greatly facilitates the design of a lunar base. And the rejection of heat is also easy since horizontal heat rejection panels are never exposed to sunlight (often, one of the main challenges is to keep a cold base and that the ISS has huge heat rejection panels).
There will also be meteorites conserved in the ice or the regolith in these craters, Earth, Mars, Ceres, perhaps Venus, and at these cryogenic temperatures, they should conserve organic substances for billions of years. 39; years. Including organic products from the first life of Earth at least. There may be small seashells and tiny pieces of ammonites in the sea since the Chicxulub incident in a shallow tropical ocean 66 million years ago. And the earthly life of many other previous impacts over the billions of years. If there was or there is life on Mars, there may be some too. It could even be that the easiest place to study the past life of Mars with exquisite details is on the Moon! Because Mars does not have quite cold spots on its surface or in depth either. Some meteorites could have passed from Mars to the Moon in less than a century, and all organic matter would have remained cryogenically since their arrival. It may also be that the life of Venus is longer if it was more habitable, as some people think. Several articles explore this idea of looking for traces of ancient life at the poles.
These old organic materials would be better preserved if the impact buried the meteorite deep in the regolith or if ejecta later covered it deep enough to be protected from cosmic radiation. We could find them by drilling or extracting ice for humans.
And most importantly, expect surprises – a place never explored before. And maybe we need a way to make the moon cool again? This has been promoted as a "non-gravity space race", but that can not really be the case, as Usain Bolt could not run to zero, just push and slide rather boring. It floats on the ground at the end of each stride. What about the lunar gravity of the Usain Bolt sprint? With a lunar background? And – on the moon, it would be so light that it could run on water! New lunar gravity sports.
Usain Bolt floats to victory in gravity race (click to watch on YouTube)
So – I think we'll send humans to Mars only if we're sensitive, after returning to the moon – and not just that, with shipments on the moon of similar length. Before our first 2 or 3 year trip to Mars and back, I think we need to be at least the same length – but for a margin of safety, slightly longer missions – where people leave with supplies for 3 years and are never restocked from Earth during their mission there. It would simulate a mission on Mars. And would be a huge challenge. There may be occasions during these three years when something unexpectedly breaks down and they can not repair it and have to return to Earth or ask for emergency supplies on Earth. This would mean that they have to do more testing until they are sure they have eliminated these problems.
I think it's only after having at least one and maybe 2 to 3 missions of this type (that could overlap) before we feel we know enough to confidently send humans into orbit Of March.
There are however other targets, close to the Earth, farther away than the Moon but not as far as Mars. An example would be 2016 HO3, a near-moon satellite of about 41 meters in diameter that varies between 38 and 100 times the distance to the moon. If you want to return to the land with a longer medevac but not as bad as Mars, then it would be a most adventurous natural place. There are many asteroids that pass much closer to Earth – but if you encounter them, you will soon be transported far into their orbit.
With 2016 HO3, you can stay there for years and always stay within 100 lunar distances all the time. It is a bit like the old guardians of the nineteenth century house living in a lighthouse on a far rock in the ocean. And at 41 meters, it's big enough to have resources that deserve to be extracted, and maybe to return to the Earth Moon system or use in situ. This is a kind of Thule ultima from our Earth Moon system (ancient Greek and Roman name for a remote location north of the known world).
Robert Zubrin called the "Double Athena" a free return mission to Mars, where the astronauts fly over Mars, fly almost halfway through Mars, fly over and return to Earth. This is a "free return," which means that, aside from minor course corrections, when you leave Earth, you are already on a trajectory that will take you back to Earth two years later. This makes it a particularly safe mission. Also during overflights and for a long time before and after, the crew is able to control the rovers on the surface of Mars with much less delay than anyone on Earth. It is therefore an excellent mission for science.
In the longer term, I think humans should study Mars in orbit and not on the surface. Because there can be biology on Mars. And if so – he could have a different biochemistry of terrestrial life.
The diseases are actually more virulent if they are not adapted to the host, which is why the bird flu is much worse than the human flu. We can not have a Mars virus. But we can have diseases like legionnaires' disease, a biofilm disease that uses the same methods to infect human amoebae and lungs. A similar disease of Mars could easily be much more dangerous. Especially if it is based on an unknown biochemistry. In the worst case, life on Earth has never developed defenses, having never met its like in billions of years, and it grows in our lungs like a culture of petri dishes, without any resistance . Joshua Lederberg, astrobiologist and microbial geneticist, Nobel laureate, expressed it as follows:
"If the Martian microorganisms manage to happen here, will they be totally mystified and defeated by the earth's metabolism, perhaps even before they defy the immune defenses?" Or will they have a day on the ground in the light of our total naivety in the face of their "aggression"??
from: "paradoxes of the host-parasite relationship"
There are many other things that could go wrong biologically. These are the worst scenarios, but we must consider them. There is no guarantee that the life of the Earth is not affected by the shock of two biospheres separated by millions of years, probably billions of years, or never having a biological link (it is not not easy to transfer life between two planets via meteorite and this may never have happened).
So, I think our first priority should be to study Mars astrobiologically and find out if it's safe to land humans there – safe for humans and the Earth – and also safe for Mars too. It would be so sad to make all Martian life extinct – and the worst in that direction is an early form of life that has not yet developed resistance to combat the most aggressive life of the modern Earth. In this direction, it could be that earthly life that resembles the microbes that grow on a petri dish of Martian life that it does not even notice and that Martian life does not recognize it as a threat before its disappearance. .
We need to know these things before we can make informed decisions.
This, in particular, is a personal view for the discussion. I think our top priority should be to develop sterile rovers for Mars. 100% sterile. It is possible to use the technology explored for Venus surface landing gear capable of withstanding temperatures that can destroy all the amino acids of the Earth. Temperatures of 300 C are sufficient for this and they have found that many commercial components are designed to withstand such temperatures in high temperature applications. There may also be other methods to obtain 100% sterile rovers.
Could we design astrobiological instruments that can also be 100% sterile? And integrate them into a 100% sterile rover without compromising sterility? If we can do this, then our rovers could explore even places with liquid water or brines without any risk of confusing the research with terrestrial biology and we can find out what's wrong. as clear as possible. .
It does not seem impossible. Brian Wilcox is working on a 100% sterile probe to descend into the Europan Ocean. It would have a vacuum insulation like a thermos, a blade that cuts ice chips that the body then melts and analyzes. It would be heated to over 500 ° C (500 ° F) during its cruise to Europa.
With sterile undercarriages, we can predict a large number on Mars – small sterilized, highly capable, then perhaps we can discover the current astrobiology and make informed decisions about whether and how to keep Mars safe Earth safe for life on Mars. And it is not excluded at this point that the only way to keep both safe is to keep the two biospheres physically separate. I do not think we should assume that it's going to go to land humans on Mars.
To know more about this: Can we get a 100% sterile electronics for a Europa lander, Enceladus, Ceres or Mars? in my "Touch Mars?" book.
What do you think of this idea? Say in the comments.
There are many other places in the solar system that we can send to humans – including the asteroid belt with sufficient materials to protect habitats and habitats with a total area of one thousand worlds the size of Mars or Earth.
Further, Titan seems to be by far the easiest place for humans outside the Earth because its atmosphere is so thick, slightly higher than the Earth and with reliable strong winds a few kilometers from the surface. surface) and other sources of energy such as "hydroelectricity" from the differences in lake levels of ethane / methane, to feed a colony.
On Titan, instead of a $ 2 million space suit, you only need a very thick wetsuit and a closed air respirator. Although the suits are thicker, they have about the same level of technology as the equipment on display in a dive shop. And you have a natural protection against the cosmic radiation of the atmosphere – and in these cold conditions, the earthly life is so cold that it can not survive and it is possible that any life of indigenous titan finds its habitats too hot for it .
So there are a lot of possibilities here.
I do not think we should focus on landing humans on Mars. I think our goal should be to orbit Mars and the two moons of Mars and explore it from orbit – and then decide what to do following all that we discover about Mars .
Scale of time – another generation – the first humans to explore Mars around the 2030s, to take off here by 2040 (if this can be done safely) ??
As for the time scale – at least 10 years, but the time only starts to run in the mid-2020s or later, because all available funding is related to the ISS . Once that reaches the end of his life – will we have the funding to go back to the moon and do something as ambitious as three-year missions to the moon without Earth supplies? I do not know. Maybe the commercial space can help there.
Be that as it may, let's assume with optimism that by the end of the 2030s we already have a decade of experience on the moon. Hopefully, we had several 3-4 year missions at L1 or L2 or similar that did not need to supply the Earth for the duration of the mission, and no incidents requiring the evacuation of the Earth or crew. back to Earth. Either that, or we have a new technology that dramatically reduces travel time to Mars, maybe a few weeks. All this is rather optimistic.
If we do this in the late 2030s, we could see our first manned missions in orbit around Mars. Meanwhile, we explore it in a robotic way. And then telerobotically from the orbit of Mars. I doubt that you can get a good estimate of the delay for a thorough astrobiological investigation. One could accelerate it with miniaturized robots, if one could send them thousands, sterile miniaturized rovers, controlled by telerobotics, with even more sophisticated instruments than today, who know to what speed the investigation could be conducted. Maybe a decade, maybe a few years, maybe just a year of study with 100 people on BFR and a thousand rovers and advanced surface life detection instruments. Remember that the surface is as large as the area of the Earth and that there are now many potential habitats to explore. It could take a long time. Then you have to study life to see if it is safe once you find it.
If it's safe for humans to land there, then I may imagine the mid-2040s, but it could be 2050 before we know enough, especially if the survey poses tough questions. and requires careful investigation. All this could easily be extended for a decade or two. If we think of a 30-year-old generation, that's about a generation in the future, assuming a strong return to the moon, and then several multi-year missions to test the systems needed for multi-year interplanetary travel.
As Chris Hadfield put it: in a New Scientist article: "We should live on the moon before a trip to Mars"
"I think we will finally live on the moon for a generation before we get to Mars.If the world and the moon were threatened and the only way to preserve our species was to leave Earth, we could go on March yesterday technology, but we would probably kill just about everyone on the way. "
"It's as if you and I were in Paris paddling the Seine in small canoes saying:" We have boats, we have paddles, let's go to Australia! "Australia: We can barely cross the Channel, we're sort of in this boat right now, a trip to Mars is conceivable but it's still way farther than most people think."
The Moon is not only safer, but it is also a natural place to start developing reliable technology for multi-year missions throughout the solar system. If we can do that, then the cost of human missions on the moon will drop dramatically to a fraction of the normal cost. Imagine what would be a cost saving if we could send a crew to the moon for two years without any refueling from Earth, as if it was an interplanetary mission to Mars? We need these exit cruises near the Earth first.
If we want to more accurately simulate a mission on Mars, we can have missions to Earth -Moon L1 or L2 positions. These are points where Earth and lunar gravity balance, allowing a spacecraft to "fly over" a single point on the near or far side of the Moon. These are not stable positions, usually the spacecraft has to do occasional station keeping maneuvers, but the "halo orbits" around them are almost stable. There are also interesting stable orbits that allow a spacecraft to approach near one or the other pole of the Moon, and even more useful, a spaceship can navigate between all these orbits at only a few meters per second from Delta V. be "stuck" in the L2 position above the moon's hidden face, unless wanting to stay there to test the psychological isolation of the impossibility to see the Earth (perhaps with simulated delays in communications). If they do not need to do it, they can move their spaceship from time to time to explore different parts of the lunar surface and support surface missions.
Once we have closed biological systems working on the moon, missions in our solar system that last a decade or more can be as easy to support as those that last two years or less. Once we have this ability, we can go to Venus, Mars and beyond, even to Mercury, asteroids and Callisto of Jupiter, then to Titan, without worrying about narrow safety margins.
Elon Musk and others often tell us that the reason is that NASA is too cautious. But they only do what politicians ask them to do for space flights, and they have little more than an advisory role. They have a lot of autonomy for unmanned spaceflight, but by tradition it is the President and Congress who decide the purpose of manned spaceflight. They would have no way to continue through the disasters of the Space Shuttle and continue to lose astronauts. They had to solve these problems. If the spaceX has similar disasters, says one of the crashes of his BFR with 100 people on board, which would lead to an immediate halt of their program as they determine what happened. They can not go into space by killing hundreds of astronauts every 20 launches. Not when we know that it can be done safely with the Soyuz TMA. And I'm sure they will not do it. It's just a matter of making things happen, I'm sure they would not be really reckless, they would do risk management like NASA does.
Indeed, I think their first customers, the commercial tourists, would actually be more sensitive to such things as NASA astronauts – the astronauts after all, many are still test pilots to date and are accustomed to dangerous missions. die. The death of Sharon Christa McAuliffe, a teacher, particularly hit people with the Challenger disaster. How would they react to a space flight crash that kills Brad Pitt, Angelina Jolle, Lady Gaga, Justin Bieber, Tom Hanks, Katy Perry, Leanordo di Caprio or Princess Beatrice to name a few who have enrolled in Virgin's suborbital hops? Galactica.
The multimillionaires and the billionaires who finance the first commercial flights of space tourism will decide with their portfolio, for example if Boeing has no crash and SpaceX does it – with whom would you fly, if you can afford to pay in orbit? ? Even though Boeing cost twice as much, I think most people would try to save more for flying with Boeing if it meant there was a much better chance of surviving the flight.
I do not think it has anything to do with NASA. If they had received a directive from the president to send humans to the moon, for example, they could meet the challenges. Put a new administrator in place if the current one was not in favor of the idea then continue and do it.
In terms of shuttles to the ISS, it is a question of politicians' vision. Ils ne peuvent que faire ce que les politiciens leur demandent de faire. Ils sont beaucoup plus libres quand il s'agit de missions sans pilote. Mais pour les missions habitées, ils ne sont pas ceux qui "payent le joueur de pipeau". Le président fait traditionnellement aux États-Unis depuis Kennedy. La NASA conseille seulement.
Si SpaceX réussit à construire le BFR d’Elon Musk et qu’il répond à leurs attentes, cela ne fait aucune différence. Il doit montrer qu’il est sûr de pénétrer dans l’espace, et plus encore avec le potentiel de 100 personnes qui meurent en une seule fois. Il aurait toujours la même situation, un système de maintien de la vie non prouvé – de toute façon pas prouvé dans l’espace – et il voudrait sûrement qu’il soit testé sur la Lune ou dans un endroit plus proche de la main. Un scénario de type Apollo 13 avec un BFR partant de la Terre pour Mars avec un échec en termes de support de vie signifie 100 personnes qui doivent durer deux ans avant de pouvoir retourner sur Terre en cas d'urgence. Je ne le vois pas comme une accélération de l’échelle de temps.
Oui, cela amène plus de personnes à voyager en une seule fois. Mais aussi plus de personnes qui mourraient dans une catastrophe de type Apollo 13 pour une mission sur Mars. Il doit donc être testé à longueur égale lors de croisières avec retour facile sur Terre en cas d’urgence et lieu naturel de le faire en L1 ou L2 et voir si 100 personnes peuvent y rester deux ans en étudiant la Lune. de l'orbite via la télérobotique sans réapprovisionnement de la Terre.
À mon avis, son BFR fait peu de différence, sauf dans la mesure où cela peut aider les humains à revenir sur la Lune, et peut-être ainsi nous aider à développer plus tôt l'expérience dont nous avons besoin pour nos voyages interplanétaires. Si nous allons le faire de manière robuste en vue de l'avenir, cela doit être testé dans des conditions d'espace plus proches, d'abord sur la Lune ou sur d'autres cibles proches. Des lieux suffisamment proches pour un réapprovisionnement d'urgence depuis la Terre et la possibilité de retourner sur Terre dans les jours qui suivent si l'intégrité de la base ou de la station ou de son support vital est menacée, par exemple après un incendie, une libération de produits chimiques ou une défaillance de l'équipement.
Cependant, si nous obtenons cette capacité de voyage interplanétaire, pas seulement Mars mais tout le système solaire, éventuellement jusqu'à Saturne et au-delà, nous seront ouverts à des missions humaines, peut-être une génération, peut-être dans les années 2040 ou 2050. si vous êtes optimiste La clé de cet objectif est le recyclage efficace des systèmes fermés, une assistance robuste et des systèmes testés lors de missions de démantèlement pluriannuelles dans le système Earth Moon. Heureusement pour nous, nous avons un monde fascinant à nos portes, la Lune, notre "huitième continent" voisin, comme on le décrit parfois, presque aussi grand que l’Asie, cinq fois plus grand que l’Australie et plus vaste que l’Afrique.
Cela est venu comme ma réponse à
sur Quora.
L'exploration humaine à ciel ouvert dans l'espace avec une protection planétaire en son cœur
Je suis un fervent partisan des humains dans l'espace, mais un vol spatial humain responsable. Risques gérés, mais pas imprudents, il s'agit d'une exploration dangereuse dans un vide difficile, et les astronautes réduisent les risques autant que possible. De plus, cela respecte l'intégrité de la science, n'éteint pas la vie autochtone jusqu'à ce que nous sachions ce qui existe et que nous puissions prendre une décision éclairée et protéger la Terre en tout temps. C'est juste raisonnable à mon avis et beaucoup sont d'accord avec cela.
Nous pouvons faire beaucoup de choses en réalisant des missions passionnantes pour les humains, en accord avec cette approche, à commencer par la Lune. Ensuite, tout le système solaire finira par nous être ouvert, mais seulement si nous développons des moyens sûrs de faire nos voyages interplanétaires. Pour les détails voir mon:
J'ai écrit trois livres sur le sujet des humains dans l'espace et des façons de faire les deux – explorer l'espace avec des humains d'une manière passionnante et ambitieuse – et en même temps le faire de manière responsable, protéger la Terre et d'autres planètes. laisser l'avenir ouvert, ne pas faire des choses qui ferment nos options avant que nous sachions ce qu'elles sont.
Mon Touch Mars? Le livre examine également l’histoire de la protection planétaire et certains des nombreux endroits possibles pour la vie dans notre système solaire, et même ailleurs, et comment nous pouvons le chercher. Plus tard, cela soulève la question plus large de savoir si nous avons besoin de "Galaxy Protection" une fois que nous avons développé la capacité de visiter d'autres étoiles, et j'examine l'idée de Galaxy Protection comme une solution au paradoxe de Fermi "Où est tout le monde?" Je couvre également les questions nitty gritty telles que les ordures sur la lune, comment vous cultiver des plantes dans l'espace, les surprises scientifiques possibles de nos explorations et de nombreux autres sujets. Je regarde les aspects pratiques de la colonisation humaine et j'examine les questions qui pourraient surgir lorsque nous essayons d'envoyer des êtres humains de plus en plus loin dans notre système solaire.
J'espère que c'est une lecture amusante. Les sections sont autonomes dans la mesure du possible afin que vous puissiez les utiliser comme un livre à plonger, plutôt que comme un livre que vous lisez d'un bout à l'autre.
Vous pouvez lire ma Touch Mars? réserver gratuitement en ligne ici:
Touchez Mars? Europa? Encelade? Ou une histoire de faux pas? (équivalent à 1938 pages imprimées sur une seule page Web, prend du temps à charger).
Vous pouvez également l'acheter sur Amazon kindle.
My other books, which cover human exploration as well as planetary protection, and explore the case for going to the Moon first (for humans), are:
My books are all designed for reading on a computer with links to click to go to the sources, and I have no plans to attempt printed versions of them.
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