I recall an article from a long time ago that basically said “astronauts report” the moon smells like spent gunpowder and outer space smell like… I think it was ozone.
What they were actually reporting was the smell of the airlocks after they returned from their excursions. The moon has no atmosphere, so it has been accumulating dust from billions of years of asteroid impacts that have never come in contact with oxygen. Many of the chemicals in the dust are oxidative and so when it is exposed to air for the first time it rapidly oxidizes just like gunpowder!
And I think the outer space report was from space walks, and the explanation was that the first time the airlock itself was exposed to hard vacuum, the surfaces of the airlock would have a reaction that left a scent of ozone.
There was some concern when Apollo 11 landed that when they repressurized the LEM with moon dust samples inside it would start a fire. I think they had a small test article that they blew a small stream of oxygen over to ensure it wouldn't auto-ignite.
At least some ISS astronauts describe smelling burnt metal after returning from EVA, if memory serves. (Others may smell ozone, I've just always remembered hearing burnt metal).
the exterior of the ISS is constantly exposed to small mounts of atomic oxygen, which is an incredibly strong oxidizer. probably in addition to ozone there is a huge variety of organic and inorganic oxides that get tracked in through the airlock.
Fun trivia (well, perhaps not fun) in the second paragraph: "the Long Duration Exposure Facility (LDEF), which was retrieved in 1990 after spending 68 months in LEO"
Long exposure, 68 months, right. But it was only supposed to be in orbit for 11! Challenger being destroyed on reentry made a mess of things.
>It was placed in low Earth orbit by Space Shuttle Challenger in April 1984. [...] At LDEF's launch, retrieval was scheduled for March 19, 1985, eleven months after deployment.[4] Schedules slipped, postponing the retrieval mission first to 1986, then indefinitely due to the Challenger disaster. After 5.7 years its orbit had decayed to about 175 nautical miles (324 km) and it was likely to burn up on reentry in a little over a month.[6][9]: 15
My UV sterilizing lights make my room smell like O3 Ozone and that smells nothing like spent gun-powder to me. The only other time I have smelled the same thing is when there has been mass lightening events in the sky. Were they talking about actual black powder or nitrocellulose? I've smelled black powder at the range when people bring out their antique rifles and that also does not smell like Ozone to me.
I also associate ozone with some electric motors, I think because they have brushes that arc during operation. Older power tools I encountered in the 1980s often did this, and you could see the blue arc if you looked into the vents at the right angle.
Brushless motors are popular now, but if you get the cheaper cordless tools they'll still have brushed motors. I have some Black & Decker 20V ones that do it. They tend to have less torque but I don't need Milwaukee or Makita tools just for diy around the house.
Photocopiers smell like ozone when they run if anyone’s forgotten the smell
Those are similar but sweeter. If I sterilize a room with UV it has a very distinct smell like nothing else aside from lightening and stun guns. I would UV the bathroom right now but then I have to vent the entire house and its 34F outside right now.
I primarily use them in the bathroom to kill off mold and bacteria about once every 3 months. I open up the water heater closet, drawers, etc... then I fire one of them up. I've used them in other places but the more they are used the more I have to vent the house.
Absolutely. I vent the house after running UV lamps using a 4400 CFM air mover. I leave the house and run errands. I have 3 of these [1]
They have a remote control that "arms" them and it starts beeping slow, the faster, then much faster then activates. It kills insects be destroying their lungs and entirely destroys mold, bacteria and even damages viral material. Hospitals run the same lamps in wings that they close down for sanitation. The entire area has to be 100% vented.
I worked for a germaphobe, and he put one of these ozone-injecting air purifiers in our tiny office. Every morning I would walk in and it felt like I was walking into a thunderstorm from the smell. No gunpowder, just thick ozone
The permissible exposure limit for ozone is 0.1 PPM.
The IDLH (Immediately Dangerous to Life and Health) level for ozone is five ppm.
That's half of chlorine which is 10 ppm.
Most major brand air purifiers put out a very minimal amount; the ionization is beneficial because it makes the really tiny (and thus most hazardous) particles clump and fall/stick to surfaces faster.
It's the offbrand units that generate lots of ozone to make people think they're "doing something", and commercial ozone generators for car/room deodorizing, that you have to be extremely careful with. Those need to be set up and then the room left for hours for the ozone to react with stuff, and then ventilated thoroughly.
Brushed DC motors (as in some drills, toothbrushes, etc.) emit ozone. Some light switches also create ozone-producing electrical arcing if you hold them perfectly between the on and off positions, or slowly cross the midpoint. (Less easy with the newer-style, less accessible rocker switches.)
Sorry for the tangent, but you sterilise a whole room with UV light? Is that efficient ? Do you do it after tidying / cleaning ? Is there a medical reason for the extra part? Is it just cool :-)
The ozone report was specifically about space walks. The gunpowder report was about moon walks.
Presumably, moonwalks would also have some ozone like the space walk did. But, maybe the burning-moon-dust gunpowder smell was a lot stronger than the vacuumed-metal/paint ozone smell.
Mars has toxic levels of perchlorates in the regolith. That will require that humans never come in contact with the regolith or things that touched it. Those space suits that dock to vehicles seem like a necessity.
Yeah, the ground on mars is literally toxic. Makes the concept of a Martian colony less appealing. Almost equal to a floating station on Venus. At least there you’d have the correct pressure. I seem to recall that the temperature on Venus at an altitude of one atmospheric pressure is manageable. It’s just also acidic. Possibility easier to deal with than perchlorates.
Another interesting one is Mercury. There is a latitude where the average ground temperature is comfortable for us. You simply need to dig in deep enough to put enough thermal mass above you to get that average rather than the swings. I don't know how deep that is on Mercury, on Earth 10 meters is enough. Real world, you'll want to go a bit farther towards the pole so your station is comfortable with the thermal load of whatever equipment you put in it.
Assuming they mean the ground acts as a heat sink, and sufficiently underground you’re not subjected to the above average heat of the day and below average cold of the night.
Without massive terraforming all of Mars is very hostile.
But having solid ground is still nice.
A workable compromise is making big habitats in a dome, that gives sunlight, but shields from radiation. And the ground needs to be processed obviously.
Gravity kind of cuts both ways. Closer to that of Earth is nearly guaranteed to be better for long term human health, but there's a possibility that martian gravity is "good enough" when supplemented with excercise while also making heavy operations and getting back out of the planet's gravity well easier.
Venus seems like a wonderful place to live, relatively speaking.
At the right altitude where you can "float" on the ocean, it's a pretty comfortable temperature and there's plenty of solar energy but you're shielded from the solar radiation. So, long term, your body will still work, assuming you can solve "the other problems."
Of course, the down-side is that there's nothing to stand on and probably more importantly, there aren't many useful materials to work with besides tons of carbon, oxygen, and nitrogen. Not much hydrogen there, so not much water, which probably is the biggest problem. One of them, anyhow. Also, there's probably not a whole lot to do besides float (zoom, actually) around and slowly go stir crazy in your bubble.
But relatively speaking, it's way nicer than living in a hole on mars where you'll slowly die from gravity sickness, or radiation poisoning, or whatever.
> Not much hydrogen there, so not much water, which probably is the biggest problem.
Actually, the cloud layer at that level is mostly sulfuric acid, from which you can get your water. It also means you need to be in a hazmat suit when you walk outside, but that's still a step up from everywhere else, where you need a bulky pressure suit instead.
Whether it is really possible, is a different question, but after you have an atmosphere, you could have engineered microorganism processing the soil etc.
To put it into perspective, we are effectively terraforming Earth today, though maybe not in a good way.
We have converted most of the land to agriculture and released maybe trillions of tons of greenhouse gas in the atmosphere, there are 8 billions of us working on it. And what did we do? Increased the global temperature 2 degrees? Made the sea level rise a couple of meters?
It may be bad for us, but compared to terraforming a planet like Mars, that's nothing, and we have the entire humanity industrial complex to do it while on mars, we need to build everything, starting from a hostile environment.
I wouldn’t go that far. It was pretty clear a long time ago that humans spending so much time filling the internet with content was going to eventually enable neural networks to pretend to communicate.
The advancements required to arrive at modern LLMs and the tech needed to get humans safely to Mars or live safely on the Moon are orders of magnitude in difference.
If you can kick off self-sustaining biological processes it’ll happen on its own eventually, but you’d just be looking at generational time scales to do it.
Of course you’ll probably have lots of side-effects.
> In that sense then the term "terraforming" is on equal footing with alchemy
NASA has proposed using "synthetic biology to take advantage of and improve upon natural perchlorate reducing bacteria. These terrestrial microbes are not directly suitable for off-world use, but their key genes pcrAB and cld...catalyze the reduction of perchlorates to chloride and oxygen" [1].
2) If you have a source of hydrogen: water. Bonus as you don't have to make the dome hold pressure. A layer of water of the right depth will generate the force needed, the structure only needs to keep itself level. The only pressure holding is outside that, enough to keep the water from boiling. And, well, it's water--if it's hit by a rock that isn't too big you'll just have hole in the top layer, easily fixed. The same general idea would work on the Moon but the water is far from transparent if you pile up enough of it and you need a lot of hydrogen.
Well, I did wrote "gives sunlight" and that is a valid reply to it. But ... I would need sunlight actually. That seems somewhat possible with light tubes, but the much nicer solution, a transparent dome to still see mars clouds at day and the stars at night, is indeed not possible with current materials.
Sadly we underestimate the liveability of this Earth. Muskism makes people believe to the false premise that we can just buy a new planet, make it habitable with magical tech. Supported with pseudoscientific buzzwords like Terraforming etc. So we can recklessly consume this planet and jump to our new home when this one depletes. No need to care about our current home because it's a jumping board. Interesting as an old Sci-Fi fantasy so it attracts smart people, but if you really think about it's just lies and stupidity.
Musk was also into the solar panels and EVs so it's not all trash the planet. Even if living on Mars or Venus isn't practical we might develop interesting tech trying.
Not exactly, it was a normal solar panel business started by Elon's cousins (SolarCity), but it wasn't going well, and in the end it was bought by Tesla for much bigger money than it was worth (let's say it was a bailout for Elon). Today Tesla solar panels are maybe 0.1%-1% of the business, they stopped giving any data on it years ago.
floating colony on venus I heard was debunked, but that was also GPT 4.1 which was misaligned so I should seek a different source, from people, when I revisit this chain of thought
Calcium perchlorate is only slightly toxic. Not good for you, but living in an environment with background radiation levels 50x higher than on Earth may be your bigger worry...
Still, I'm pretty sure we have plenty of people who wouldn't mind giving it a try.
Personally, I suspect all anoxic environments will turn out to be unhealthy for humans. You'll have a bunch of reactive stuff about that on Earth would have been neutralized long ago.
If this fact piques your interest, the book Delta-v by Daniel Suarez glances off this fact and uses it to justify exploring asteroid mining instead of a colony on Mars.
Or effective decontamination performed in the airlock. There was a recent demonstration of an electrostatic repulsion device reducing dust on suit fabric which might help with sticking. And an air shower like used for clean rooms does not seem too far out.
Could the suit itself be used as a type of airlock, to leave outside things outside?
For example, mounting yourself onto a wall, then the back/whatever of the suit opens to the inside, and you hop out? (yes, there would be some dust recovery required, but minimal in comparison)
The challenge with the "suits stay outside" model is that you basically need some kind of airlock between the suit hatch and the ship hatch. You might imagine both hatches get contaminated when the suit is detached. Then when you dock, that whole between-hatch space needs to be decontaminated before you can open the two hatches, because the outside of the suit hatch brought that stuff into the airlock.
There has been some great research into laser or solar sintering of regolith, and one of my first questions was if the resulting material is safe for humans.
> "I think one of the most aggravating, restricting facets of lunar surface exploration is the dust and its adherence to everything no matter what kind of material, whether it be skin, suit material, metal, no matter what it be and its restrictive, friction-like action to everything it gets on [...] the simple large-tolerance mechanical devices on the Rover began to show the effect of dust as the EVAs went on. By the middle or the end of the third EVA, simple things like bag locks and the lock which held the pallet on the Rover began not only to malfunction but to not function at all. They effectively froze. We tried to dust them and bang the dust off and clean them, and there was just no way. The effect of dust on mirrors, cameras, and checklists is phenomenal. You have to live with it but you're continually fighting the dust problem both outside and inside the spacecraft. Once you get inside the spacecraft, as much as you dust yourself, you start taking off the suits and you have dust on your hands and your face and you're walking in it. You can be as careful in cleaning up as you want to, but it just sort of inhabits every nook and cranny in the spacecraft and every pore in your skin [...]" Eugene Cernan, Apollo 17 debrief[1]
An interactive microscope of regolith.[2] Like tiny broken glass, hard as rock, and sticking to everything like static-charged packing peanuts.
"In addition the Moon has no atmosphere and is constantly bombarded by radiation from the Sun that causes the soil to become electrostatically charged." - You can use a magnetic or electric field to push the soil away
Even with actual asbestos, the risk goes up a lot with duration and intensity of exposure. Probably, the risks of getting cancer from a brief exposure is fairly low, and combined with the ridiculously small sample size of only 12 people to ever set foot on the moon, it's natural that none of them got "moon cancer". That said, with asbesto, it's still possible to get cancer even from brief exposures:
> Although it is clear that the health risks from asbestos exposure increase with heavier exposure and longer exposure time, investigators have found asbestos-related diseases in individuals with only brief exposures. Generally, those who develop asbestos-related diseases show no signs of illness for a long time after exposure. It can take from 10 to 40 years or more for symptoms of an asbestos-related condition to appear. [1]
Only 4 are still alive, all in their 90s so that’d be a long time - even if some do have cancer at this stage it’s not likely to affect life expectancy I guess.
We also have to remember that those astronauts were some of the most physically fit individuals in a nation of hundreds of millions which may skew the expected medical outcomes. Especially if we assume they always had the best healthcare available, if from nothing else than doctors asking similiar qiestions about the effects of space travel.
That's just simply not true at all, I don't know where you're getting this idea. Literally every Olympic athlete was more fit that an any astronaut ever.
The military does not survey the population and then select the fittest. So, as a function, it cannot actually perform as you say.
It's the same with F1. "We have the best drivers in the world!" You have the best drivers from the self-selection mechanism you impose on the sport. There are zero reasons to think these categories have good overlap.
They don't need to have sampled the entire population to have ended up with some of the most x individuals of the nation of y population size, they just need a large enough pool that the top end up among some of the best.
The exposure was brief, too. Wikipedia says mesothelioma has been known to develop from exposures of "only" 1 month. That's a scary short time if it's in your home or workplace, but comfortably longer than an Apollo mission. Could be an issue for a future base, though.
I mean Neil Armstrong literally smoked and did not "believe" in excercise so they were absolutely not the most physically fittest people. They were just freaks in terms of enduring a lot of stress tests. Physical endurance is just one aspect they train for. Other aspects were much more valued like them being military flight pilots/smart enough to understand the systems/mentally strong enough to not break down etc. You were not selecting for absolute raw fitness for the apollo missions.
They didn't select for pure physical fitness but they were already selected for fitness as a pilot and then again when they were selected from the pilots to train as an astonaut. Its not like they just picked arbitrarily from the potential pool of candidates and gambled on getting better than average.
Part of what makes asbestos (and also fiberglass) dangerous, isn't just the sharpness but also the long shape which means that macrophages can't engulf them.
Moon dust is still problematic since although smaller it also can't be digested by macrophages and it's believed it would accumulate in the lungs, building up on repeated exposure.
I walked up to the flows on Fagradalsfjall when it was erupting a couple of years ago, and I found the cinereous, sulfurous air to be very medicinal and clearing. I'm not sure it'd have good for me for more than a few hours, but as it was, it was great. I occasionally wish I were able to just have a chamber with that air in it.
There are some saunas on Iceland that expose you to earth gasses, might be exactly the kind of chamber you are after. I've visited one, and it was unfortunately cold for a sauna because that's naturally varying too.
> If you want to get depressed about all the problems with trying to colonize Mars
I had the opposite reaction. I thought it set forward a realistic set of challenges we have to solve and experiments we have to do before building anything more than a research outpost on Mars. That, in turn, makes a permanent Moon base more valuable.
Standout problems were low- and zero-g trauma medicine, plumbing (something Artemis II started working on) and mammalian reproduction.
This is on my reading list. I've read synopses of it, and I don't think it's going to change my mind a lot. I'm still long-term pro-space-exploration, but even before this book I'd come to the conclusion that this is a lot harder than naive nerds tend to think. I think it's worth doing and probably will be done eventually, but it's gonna take a while.
I've had the thought for some time now that the most viable path to settlement in space -- if humans actually decide they want to do it -- is to settle space. Not the Moon, or Mars, or Venus, or anything else, but space itself.
In space you can build big rings and spin them for 1g gravity. We don't know if 1/6 or 1/3 gravity is enough for us to reproduce and prosper, but we know 1g is. Your environment is hermetically sealed and you control what comes in and out. You could, once you get good at this, actually create hyper-habitable environments tuned to be ideal for human life. People aren't tracking in nasty asbestos-like regolith or perchlorates or anything else you don't want.
Most reasonable near-mid term proposals for living on Mars or the Moon I've read about call for spending most time underground. Going there to do that seems pointless. Living in space itself could be much nicer.
The interior of such a ring would look nothing like this very Hollywood "luxury hotel" thing, but this little short film gives you a sense of what the relationship to the external space environment might be like:
Radiation is still an issue, but there's ideas for that that could work for a ring in hard space vacuum that don't work as well on a planet. One is to put a big superconductor around the ring and give it a magnetosphere. The whole habitat is a big electromagnet. Most cosmic rays and solar particles are charged. The power requirements are not as great as you'd think.
For resources asteroids are probably better than planets. The solar system is full of asteroids that appear, from what we've seen, to be incredibly rich in raw materials, and these bodies have such low gravity that you could literally pull up next to them and go dig stuff out of them. The delta-V requirements of sending stuff back to your space-city are literally at the scale of "throw it real hard." Their low mass also means you don't have to dig deep and the heavy elements didn't sink to the core. You're going to find gigantic amounts of stuff like gold, platinum, pure iridium, fissile materials, etc.
Free living space habitats could move around. There could be moving towns and cities, more or less, that could tour the solar system and pick up resources and rendezvous with each other. Think steampunk style traction cities in space, kind of.
Politically you leave behind at least some of terrestrial politics. I'm not naive enough to think people would never find anything to fight about. We're good at coming up with stuff to fight about. But the notion of battling over land pretty much goes away. Space is called space for a reason. Culture wars become less relevant if everyone's town is mobile and if you don't like your neighbors you just move your whole "pod" around. Resources seem very abundant. I don't see a ton of resource competition unless we discover some critical or massively valuable resources that genuinely are rare and available in only a few places.
In the very long term, this path leads to the evolution of an actual spacefaring civilization rather than simply a repeat of terrestrial politics on another planet. Generation ships to the stars would be a natural evolution of this. After doing this for a few hundred or a few thousand years, we'd get so good at it that the idea of a caravan of these mobile cities departing for Centauri or Tau Ceti becomes imaginable and not a total suicide mission.
Compared to this I think going to Mars is a dead end. Even if we go there and survive and prosper, now we're just doing planetary civilization again. We're back to squabbling over dirt. The real evolutionary leap is doing something different. Fish didn't come on land to stay fish.
But there's also an argument that there's no point in trying until we at least have a couple of key technologies: fusion, very good automated manufacturing, and very good robotics. Fusion is key for enabling scalable power and mobility. Automated manufacturing and very good robotics are probably key to self-sufficiency.
Trying to do the "real space age" before the key technologies exist might be akin to, say, trying to start the EV revolution with lead-acid batteries or the PC revolution with vacuum tubes. While it's technically possible to try, it's just not going to "take."
That’s such a weirdly specific detail but also kinda fascinating. Imagine going to the Moon and the first thing you notice is “huh… smells like gunpowder.
I just had a filling replaced at the dentist yesterday and when he was grinding away at it to shape it, I would get a terrible whiff of something like gunpowder. It was quite disturbing.
But now I can just tell everyone my tooth is filled with moon dust.
Cue Cave Johnson: “The bean counters told me we literally could not afford to buy seven dollars worth of moon rocks, much less seventy million. Bought 'em anyway. Ground 'em up, mixed em into a gel. And guess what? Ground up moon rocks are pure poison. I am deathly ill.”
I recall an article from a long time ago that basically said “astronauts report” the moon smells like spent gunpowder and outer space smell like… I think it was ozone.
What they were actually reporting was the smell of the airlocks after they returned from their excursions. The moon has no atmosphere, so it has been accumulating dust from billions of years of asteroid impacts that have never come in contact with oxygen. Many of the chemicals in the dust are oxidative and so when it is exposed to air for the first time it rapidly oxidizes just like gunpowder!
And I think the outer space report was from space walks, and the explanation was that the first time the airlock itself was exposed to hard vacuum, the surfaces of the airlock would have a reaction that left a scent of ozone.
There was some concern when Apollo 11 landed that when they repressurized the LEM with moon dust samples inside it would start a fire. I think they had a small test article that they blew a small stream of oxygen over to ensure it wouldn't auto-ignite.
At least some ISS astronauts describe smelling burnt metal after returning from EVA, if memory serves. (Others may smell ozone, I've just always remembered hearing burnt metal).
the exterior of the ISS is constantly exposed to small mounts of atomic oxygen, which is an incredibly strong oxidizer. probably in addition to ozone there is a huge variety of organic and inorganic oxides that get tracked in through the airlock.
https://en.wikipedia.org/wiki/Materials_International_Space_...
Fun trivia (well, perhaps not fun) in the second paragraph: "the Long Duration Exposure Facility (LDEF), which was retrieved in 1990 after spending 68 months in LEO"
Long exposure, 68 months, right. But it was only supposed to be in orbit for 11! Challenger being destroyed on reentry made a mess of things.
https://en.wikipedia.org/wiki/Long_Duration_Exposure_Facilit...
>It was placed in low Earth orbit by Space Shuttle Challenger in April 1984. [...] At LDEF's launch, retrieval was scheduled for March 19, 1985, eleven months after deployment.[4] Schedules slipped, postponing the retrieval mission first to 1986, then indefinitely due to the Challenger disaster. After 5.7 years its orbit had decayed to about 175 nautical miles (324 km) and it was likely to burn up on reentry in a little over a month.[6][9]: 15
Challenger was destroyed on launch, not reentry.
Yeah it was Columbia that was destroyed on reentry (17 years later).
I always heard burnt steak.
My UV sterilizing lights make my room smell like O3 Ozone and that smells nothing like spent gun-powder to me. The only other time I have smelled the same thing is when there has been mass lightening events in the sky. Were they talking about actual black powder or nitrocellulose? I've smelled black powder at the range when people bring out their antique rifles and that also does not smell like Ozone to me.
‘Ozone’ is the smell of ionisation, ‘gunpowder’ the smell of oxidisation.
Photocopiers smell like ozone when they run if anyone’s forgotten the smell
I also associate ozone with some electric motors, I think because they have brushes that arc during operation. Older power tools I encountered in the 1980s often did this, and you could see the blue arc if you looked into the vents at the right angle.
Brushless motors are popular now, but if you get the cheaper cordless tools they'll still have brushed motors. I have some Black & Decker 20V ones that do it. They tend to have less torque but I don't need Milwaukee or Makita tools just for diy around the house.
Photocopiers smell like ozone when they run if anyone’s forgotten the smell
Those are similar but sweeter. If I sterilize a room with UV it has a very distinct smell like nothing else aside from lightening and stun guns. I would UV the bathroom right now but then I have to vent the entire house and its 34F outside right now.
Side quest: Can you tell more about the UV sterilisation thing? Why do you do that? How often? Where? It seems like such a specific thing to do.
I primarily use them in the bathroom to kill off mold and bacteria about once every 3 months. I open up the water heater closet, drawers, etc... then I fire one of them up. I've used them in other places but the more they are used the more I have to vent the house.
I don't think any of you should want to be smelling Ozone.
Diatomic oxygen is already a highly reactive fuel that is killing us and giving us cancer every single day. The ozone species is even more oxidative.
Oxygen is how we move about the energy gradient, but it's also killing us. Ozone is worse.
"Air purifiers" with ionization are probably not worth the squeeze.
Aside from "killing us and giving us cancer every single day", isn't "diatomic oxygen" the stuff we breathe every single minute and need to survive?
I'm not normally one to miss the sarcastic or satirical posts, but this one seems oddly earnest.
> isn't "diatomic oxygen" the stuff we breathe every single minute and need to survive?
I think they're referring to oxidative stress [1] caused by cellular respiration.
[1] https://en.wikipedia.org/wiki/Oxidative_stress
Absolutely. I vent the house after running UV lamps using a 4400 CFM air mover. I leave the house and run errands. I have 3 of these [1]
They have a remote control that "arms" them and it starts beeping slow, the faster, then much faster then activates. It kills insects be destroying their lungs and entirely destroys mold, bacteria and even damages viral material. Hospitals run the same lamps in wings that they close down for sanitation. The entire area has to be 100% vented.
[1] - https://www.amazon.com/AeraLight-Whole-Surface-UV-Sanitizer/...
I worked for a germaphobe, and he put one of these ozone-injecting air purifiers in our tiny office. Every morning I would walk in and it felt like I was walking into a thunderstorm from the smell. No gunpowder, just thick ozone
In general, if you can smell ozone, you should NOT be in that place.
The permissible exposure limit for ozone is 0.1 PPM.
The IDLH (Immediately Dangerous to Life and Health) level for ozone is five ppm.
That's half of chlorine which is 10 ppm.
Most major brand air purifiers put out a very minimal amount; the ionization is beneficial because it makes the really tiny (and thus most hazardous) particles clump and fall/stick to surfaces faster.
It's the offbrand units that generate lots of ozone to make people think they're "doing something", and commercial ozone generators for car/room deodorizing, that you have to be extremely careful with. Those need to be set up and then the room left for hours for the ozone to react with stuff, and then ventilated thoroughly.
Brushed DC motors (as in some drills, toothbrushes, etc.) emit ozone. Some light switches also create ozone-producing electrical arcing if you hold them perfectly between the on and off positions, or slowly cross the midpoint. (Less easy with the newer-style, less accessible rocker switches.)
The only thing you're doing by sterilizing your house like that is making your immune system weaker.
Humans are built to withstand a constant assault on their immune systems. We couldn't have survived if we didn't.
Don't worry I know what I am doing.
Careful. The venn diagram bubble depicting your statement overlaps heavily with the anti-vaccine bubble.
Its a bit naieve to claim that cleaning one's home will result in an extinction of enough microbes so as to be threatening to our immune system.
Thank you! I wish I could upvote this twice, fellow redditor!
You might be smelling the oxidation of biologicals via ozone and UV might have the same chemical effect
Sorry for the tangent, but you sterilise a whole room with UV light? Is that efficient ? Do you do it after tidying / cleaning ? Is there a medical reason for the extra part? Is it just cool :-)
The ozone report was specifically about space walks. The gunpowder report was about moon walks.
Presumably, moonwalks would also have some ozone like the space walk did. But, maybe the burning-moon-dust gunpowder smell was a lot stronger than the vacuumed-metal/paint ozone smell.
Mars has toxic levels of perchlorates in the regolith. That will require that humans never come in contact with the regolith or things that touched it. Those space suits that dock to vehicles seem like a necessity.
https://en.wikipedia.org/wiki/Perchlorate#On_Mars
Yeah, the ground on mars is literally toxic. Makes the concept of a Martian colony less appealing. Almost equal to a floating station on Venus. At least there you’d have the correct pressure. I seem to recall that the temperature on Venus at an altitude of one atmospheric pressure is manageable. It’s just also acidic. Possibility easier to deal with than perchlorates.
Another interesting one is Mercury. There is a latitude where the average ground temperature is comfortable for us. You simply need to dig in deep enough to put enough thermal mass above you to get that average rather than the swings. I don't know how deep that is on Mercury, on Earth 10 meters is enough. Real world, you'll want to go a bit farther towards the pole so your station is comfortable with the thermal load of whatever equipment you put in it.
the swings?
Assuming they mean the ground acts as a heat sink, and sufficiently underground you’re not subjected to the above average heat of the day and below average cold of the night.
Without massive terraforming all of Mars is very hostile.
But having solid ground is still nice.
A workable compromise is making big habitats in a dome, that gives sunlight, but shields from radiation. And the ground needs to be processed obviously.
The advantage of Venus to me is is gravity.
Gravity kind of cuts both ways. Closer to that of Earth is nearly guaranteed to be better for long term human health, but there's a possibility that martian gravity is "good enough" when supplemented with excercise while also making heavy operations and getting back out of the planet's gravity well easier.
I wonder if it will turn out to be easier to adapt lifeforms to the planets than to try to adapt the planets to the lifeforms.
Both probably, but you cannot really adapt life to no water and hard radiation. (at most sustain it in stasis, but not growing)
Venus seems like a wonderful place to live, relatively speaking.
At the right altitude where you can "float" on the ocean, it's a pretty comfortable temperature and there's plenty of solar energy but you're shielded from the solar radiation. So, long term, your body will still work, assuming you can solve "the other problems."
Of course, the down-side is that there's nothing to stand on and probably more importantly, there aren't many useful materials to work with besides tons of carbon, oxygen, and nitrogen. Not much hydrogen there, so not much water, which probably is the biggest problem. One of them, anyhow. Also, there's probably not a whole lot to do besides float (zoom, actually) around and slowly go stir crazy in your bubble.
But relatively speaking, it's way nicer than living in a hole on mars where you'll slowly die from gravity sickness, or radiation poisoning, or whatever.
> Not much hydrogen there, so not much water, which probably is the biggest problem.
Actually, the cloud layer at that level is mostly sulfuric acid, from which you can get your water. It also means you need to be in a hazmat suit when you walk outside, but that's still a step up from everywhere else, where you need a bulky pressure suit instead.
If we terraform mars, isn't the dirt still toxic?
No, as terraforming means changing that.
Whether it is really possible, is a different question, but after you have an atmosphere, you could have engineered microorganism processing the soil etc.
Just exposing the Martian soil to water for some time is enough to destroy the perchlorates.
(Turns out there's a region in Antarctic with them too, so we can always test things there.)
In that sense then the term "terraforming" is on equal footing with alchemy.
Doing something like that at planetary scale is science fiction anyway even if we did have the tech to do it.
To put it into perspective, we are effectively terraforming Earth today, though maybe not in a good way.
We have converted most of the land to agriculture and released maybe trillions of tons of greenhouse gas in the atmosphere, there are 8 billions of us working on it. And what did we do? Increased the global temperature 2 degrees? Made the sea level rise a couple of meters?
It may be bad for us, but compared to terraforming a planet like Mars, that's nothing, and we have the entire humanity industrial complex to do it while on mars, we need to build everything, starting from a hostile environment.
Talking to computers and expecting computers to answer coherent English was science fiction 4 years ago. Don’t lose faith
I wouldn’t go that far. It was pretty clear a long time ago that humans spending so much time filling the internet with content was going to eventually enable neural networks to pretend to communicate.
The advancements required to arrive at modern LLMs and the tech needed to get humans safely to Mars or live safely on the Moon are orders of magnitude in difference.
Keeping humans alive is hard.
I would not be so pessimistic. Look what the https://en.wikipedia.org/wiki/Cyanobacteria have done for our atmosphere.
Maybe we’ll turn all of Mars into paperclips with our efforts! Glorious paperclips. First Mars, then the universe!
If you can kick off self-sustaining biological processes it’ll happen on its own eventually, but you’d just be looking at generational time scales to do it.
Of course you’ll probably have lots of side-effects.
> In that sense then the term "terraforming" is on equal footing with alchemy
NASA has proposed using "synthetic biology to take advantage of and improve upon natural perchlorate reducing bacteria. These terrestrial microbes are not directly suitable for off-world use, but their key genes pcrAB and cld...catalyze the reduction of perchlorates to chloride and oxygen" [1].
[1] https://www.nasa.gov/general/detoxifying-mars/
Which dome construction material would be transparent to sunlight but block ionizing radiation?
1) Why do you need sunlight?
2) If you have a source of hydrogen: water. Bonus as you don't have to make the dome hold pressure. A layer of water of the right depth will generate the force needed, the structure only needs to keep itself level. The only pressure holding is outside that, enough to keep the water from boiling. And, well, it's water--if it's hit by a rock that isn't too big you'll just have hole in the top layer, easily fixed. The same general idea would work on the Moon but the water is far from transparent if you pile up enough of it and you need a lot of hydrogen.
Well, I did wrote "gives sunlight" and that is a valid reply to it. But ... I would need sunlight actually. That seems somewhat possible with light tubes, but the much nicer solution, a transparent dome to still see mars clouds at day and the stars at night, is indeed not possible with current materials.
Since the perchlorate is generated by reaction with sunlight, it might be limited to a surface layer.
Well, I guess that's what regolith means.
Regolith is all the loose stuff, everything that's not bedrock, even if it might be quite deep.
Rocket fuel for the taking?
Sadly we underestimate the liveability of this Earth. Muskism makes people believe to the false premise that we can just buy a new planet, make it habitable with magical tech. Supported with pseudoscientific buzzwords like Terraforming etc. So we can recklessly consume this planet and jump to our new home when this one depletes. No need to care about our current home because it's a jumping board. Interesting as an old Sci-Fi fantasy so it attracts smart people, but if you really think about it's just lies and stupidity.
Musk was also into the solar panels and EVs so it's not all trash the planet. Even if living on Mars or Venus isn't practical we might develop interesting tech trying.
Wasn’t the solar panels thing just some financial fraud scheme?
Not exactly, it was a normal solar panel business started by Elon's cousins (SolarCity), but it wasn't going well, and in the end it was bought by Tesla for much bigger money than it was worth (let's say it was a bailout for Elon). Today Tesla solar panels are maybe 0.1%-1% of the business, they stopped giving any data on it years ago.
If so, they are still going https://www.tesla.com/solarpanels so I guess not
floating colony on venus I heard was debunked, but that was also GPT 4.1 which was misaligned so I should seek a different source, from people, when I revisit this chain of thought
Mars is so bad, y'all.
Calcium perchlorate is only slightly toxic. Not good for you, but living in an environment with background radiation levels 50x higher than on Earth may be your bigger worry...
Still, I'm pretty sure we have plenty of people who wouldn't mind giving it a try.
Personally, I suspect all anoxic environments will turn out to be unhealthy for humans. You'll have a bunch of reactive stuff about that on Earth would have been neutralized long ago.
> That will require that humans never come in contact with the regolith or things that touched it.
It’s really only a concern if you ingest it.
If this fact piques your interest, the book Delta-v by Daniel Suarez glances off this fact and uses it to justify exploring asteroid mining instead of a colony on Mars.
I'm not impressed with his science.
Or effective decontamination performed in the airlock. There was a recent demonstration of an electrostatic repulsion device reducing dust on suit fabric which might help with sticking. And an air shower like used for clean rooms does not seem too far out.
Is that required?
Could the suit itself be used as a type of airlock, to leave outside things outside?
For example, mounting yourself onto a wall, then the back/whatever of the suit opens to the inside, and you hop out? (yes, there would be some dust recovery required, but minimal in comparison)
The challenge with the "suits stay outside" model is that you basically need some kind of airlock between the suit hatch and the ship hatch. You might imagine both hatches get contaminated when the suit is detached. Then when you dock, that whole between-hatch space needs to be decontaminated before you can open the two hatches, because the outside of the suit hatch brought that stuff into the airlock.
Someone else linked to this: https://en.wikipedia.org/wiki/Space_Exploration_Vehicle#Spec...
edit: in that context^ search for "SEV suitport design" find NASA has written some docs on the matter, eg https://ntrs.nasa.gov/api/citations/20130013652/downloads/20...
> mounting yourself onto a wall, then the back/whatever of the suit opens to the inside, and you hop out?
Isn't there a plan for the Artemis lunar rover to be configured this way? The outside of the suit never comes inside the rover.
there's a great PBS Space Time for that (of course)
https://www.youtube.com/watch?v=O5FqozA4IpA
TIL
This is a big perk of the newer lunar rover design, wherein the suits stay outside the vehicle - https://en.wikipedia.org/wiki/Space_Exploration_Vehicle#Spec...
There has been some great research into laser or solar sintering of regolith, and one of my first questions was if the resulting material is safe for humans.
https://www.nature.com/articles/s41598-023-42008-1
> "I think one of the most aggravating, restricting facets of lunar surface exploration is the dust and its adherence to everything no matter what kind of material, whether it be skin, suit material, metal, no matter what it be and its restrictive, friction-like action to everything it gets on [...] the simple large-tolerance mechanical devices on the Rover began to show the effect of dust as the EVAs went on. By the middle or the end of the third EVA, simple things like bag locks and the lock which held the pallet on the Rover began not only to malfunction but to not function at all. They effectively froze. We tried to dust them and bang the dust off and clean them, and there was just no way. The effect of dust on mirrors, cameras, and checklists is phenomenal. You have to live with it but you're continually fighting the dust problem both outside and inside the spacecraft. Once you get inside the spacecraft, as much as you dust yourself, you start taking off the suits and you have dust on your hands and your face and you're walking in it. You can be as careful in cleaning up as you want to, but it just sort of inhabits every nook and cranny in the spacecraft and every pore in your skin [...]" Eugene Cernan, Apollo 17 debrief[1]
An interactive microscope of regolith.[2] Like tiny broken glass, hard as rock, and sticking to everything like static-charged packing peanuts.
An old tech memo and paper.[3][4]
[1] https://an.rsl.wustl.edu/apollo/data/A17/resources/a17-techd... page "27-28" 258, 50 in pdf. Lots of other mentions of dust. [2] interactive microscope of regolith https://virtualmicroscope.org/sites/default/files/html5Asset... [3] The Effects of Lunar Dust on EVA Systems During the Apollo Missions https://ntrs.nasa.gov/api/citations/20050160460/downloads/20... [4] IMPACT OF DUST ON LUNAR EXPLORATION https://adsabs.harvard.edu/pdf/2007ESASP.643..239S
As a huge space nerd, I would like to point out that space, and other planetary bodies appear to really suck.
It seems to be under-reported that the Earth is pretty nice.
Sadly, it's populated.
Hey, in other under-reported news: until the Earth reaches 100% de-population... it can in-fact get worse!
Let's take a moment to appreciate that we still live on a non-depopulated planet. The Peter Thiel has not yet achieved its ultimate goal.
They describe the dust on the moon as,
> Fine like powder, but sharp like glass
Sounds scary. But totally worth it!
"In addition the Moon has no atmosphere and is constantly bombarded by radiation from the Sun that causes the soil to become electrostatically charged." - You can use a magnetic or electric field to push the soil away
Have any of them developed cancer from the space asbestos yet?
Even with actual asbestos, the risk goes up a lot with duration and intensity of exposure. Probably, the risks of getting cancer from a brief exposure is fairly low, and combined with the ridiculously small sample size of only 12 people to ever set foot on the moon, it's natural that none of them got "moon cancer". That said, with asbesto, it's still possible to get cancer even from brief exposures:
> Although it is clear that the health risks from asbestos exposure increase with heavier exposure and longer exposure time, investigators have found asbestos-related diseases in individuals with only brief exposures. Generally, those who develop asbestos-related diseases show no signs of illness for a long time after exposure. It can take from 10 to 40 years or more for symptoms of an asbestos-related condition to appear. [1]
[1] https://www.cancer.gov/about-cancer/causes-prevention/risk/s...
Only 4 are still alive, all in their 90s so that’d be a long time - even if some do have cancer at this stage it’s not likely to affect life expectancy I guess.
We also have to remember that those astronauts were some of the most physically fit individuals in a nation of hundreds of millions which may skew the expected medical outcomes. Especially if we assume they always had the best healthcare available, if from nothing else than doctors asking similiar qiestions about the effects of space travel.
That's just simply not true at all, I don't know where you're getting this idea. Literally every Olympic athlete was more fit that an any astronaut ever.
The military does not survey the population and then select the fittest. So, as a function, it cannot actually perform as you say.
It's the same with F1. "We have the best drivers in the world!" You have the best drivers from the self-selection mechanism you impose on the sport. There are zero reasons to think these categories have good overlap.
They don't need to have sampled the entire population to have ended up with some of the most x individuals of the nation of y population size, they just need a large enough pool that the top end up among some of the best.
The exposure was brief, too. Wikipedia says mesothelioma has been known to develop from exposures of "only" 1 month. That's a scary short time if it's in your home or workplace, but comfortably longer than an Apollo mission. Could be an issue for a future base, though.
It definitely puts a damper on my personal enthusiasm for visiting the moon hotel, or even encouraging researchers to live there.
I mean Neil Armstrong literally smoked and did not "believe" in excercise so they were absolutely not the most physically fittest people. They were just freaks in terms of enduring a lot of stress tests. Physical endurance is just one aspect they train for. Other aspects were much more valued like them being military flight pilots/smart enough to understand the systems/mentally strong enough to not break down etc. You were not selecting for absolute raw fitness for the apollo missions.
They didn't select for pure physical fitness but they were already selected for fitness as a pilot and then again when they were selected from the pilots to train as an astonaut. Its not like they just picked arbitrarily from the potential pool of candidates and gambled on getting better than average.
Part of what makes asbestos (and also fiberglass) dangerous, isn't just the sharpness but also the long shape which means that macrophages can't engulf them.
Moon dust is still problematic since although smaller it also can't be digested by macrophages and it's believed it would accumulate in the lungs, building up on repeated exposure.
Sounds to me like the threat would be silicosis.
Isn't this why NASA is developing the Electrodynamic Dust Shield [1] system?
[1] https://www.nasa.gov/image-article/nasas-dust-shield-success...
we have similar problems with volcanic ash on earth
Exactly, but the lack of a water cycle on the moon means that all the dust is sharp and always will be.
It will irritate human mucus membranes whenever it comes in contact. Irritate lungs, eyes, skin.
It degrades rubber seals.
I walked up to the flows on Fagradalsfjall when it was erupting a couple of years ago, and I found the cinereous, sulfurous air to be very medicinal and clearing. I'm not sure it'd have good for me for more than a few hours, but as it was, it was great. I occasionally wish I were able to just have a chamber with that air in it.
There are some saunas on Iceland that expose you to earth gasses, might be exactly the kind of chamber you are after. I've visited one, and it was unfortunately cold for a sauna because that's naturally varying too.
If you want to get depressed about all the problems with trying to colonize Mars, I recommend A City on Mars: https://www.acityonmars.com/
It's by the cartoonist of Saturday Morning Breakfast Cereal and his wife (the one with an actual science PhD). https://www.smbc-comics.com/
> If you want to get depressed about all the problems with trying to colonize Mars
I had the opposite reaction. I thought it set forward a realistic set of challenges we have to solve and experiments we have to do before building anything more than a research outpost on Mars. That, in turn, makes a permanent Moon base more valuable.
Standout problems were low- and zero-g trauma medicine, plumbing (something Artemis II started working on) and mammalian reproduction.
This is on my reading list. I've read synopses of it, and I don't think it's going to change my mind a lot. I'm still long-term pro-space-exploration, but even before this book I'd come to the conclusion that this is a lot harder than naive nerds tend to think. I think it's worth doing and probably will be done eventually, but it's gonna take a while.
I've had the thought for some time now that the most viable path to settlement in space -- if humans actually decide they want to do it -- is to settle space. Not the Moon, or Mars, or Venus, or anything else, but space itself.
In space you can build big rings and spin them for 1g gravity. We don't know if 1/6 or 1/3 gravity is enough for us to reproduce and prosper, but we know 1g is. Your environment is hermetically sealed and you control what comes in and out. You could, once you get good at this, actually create hyper-habitable environments tuned to be ideal for human life. People aren't tracking in nasty asbestos-like regolith or perchlorates or anything else you don't want.
Most reasonable near-mid term proposals for living on Mars or the Moon I've read about call for spending most time underground. Going there to do that seems pointless. Living in space itself could be much nicer.
The interior of such a ring would look nothing like this very Hollywood "luxury hotel" thing, but this little short film gives you a sense of what the relationship to the external space environment might be like:
https://www.youtube.com/watch?v=iiPmgW21rwY
Radiation is still an issue, but there's ideas for that that could work for a ring in hard space vacuum that don't work as well on a planet. One is to put a big superconductor around the ring and give it a magnetosphere. The whole habitat is a big electromagnet. Most cosmic rays and solar particles are charged. The power requirements are not as great as you'd think.
For resources asteroids are probably better than planets. The solar system is full of asteroids that appear, from what we've seen, to be incredibly rich in raw materials, and these bodies have such low gravity that you could literally pull up next to them and go dig stuff out of them. The delta-V requirements of sending stuff back to your space-city are literally at the scale of "throw it real hard." Their low mass also means you don't have to dig deep and the heavy elements didn't sink to the core. You're going to find gigantic amounts of stuff like gold, platinum, pure iridium, fissile materials, etc.
Free living space habitats could move around. There could be moving towns and cities, more or less, that could tour the solar system and pick up resources and rendezvous with each other. Think steampunk style traction cities in space, kind of.
Politically you leave behind at least some of terrestrial politics. I'm not naive enough to think people would never find anything to fight about. We're good at coming up with stuff to fight about. But the notion of battling over land pretty much goes away. Space is called space for a reason. Culture wars become less relevant if everyone's town is mobile and if you don't like your neighbors you just move your whole "pod" around. Resources seem very abundant. I don't see a ton of resource competition unless we discover some critical or massively valuable resources that genuinely are rare and available in only a few places.
In the very long term, this path leads to the evolution of an actual spacefaring civilization rather than simply a repeat of terrestrial politics on another planet. Generation ships to the stars would be a natural evolution of this. After doing this for a few hundred or a few thousand years, we'd get so good at it that the idea of a caravan of these mobile cities departing for Centauri or Tau Ceti becomes imaginable and not a total suicide mission.
Compared to this I think going to Mars is a dead end. Even if we go there and survive and prosper, now we're just doing planetary civilization again. We're back to squabbling over dirt. The real evolutionary leap is doing something different. Fish didn't come on land to stay fish.
But there's also an argument that there's no point in trying until we at least have a couple of key technologies: fusion, very good automated manufacturing, and very good robotics. Fusion is key for enabling scalable power and mobility. Automated manufacturing and very good robotics are probably key to self-sufficiency.
Trying to do the "real space age" before the key technologies exist might be akin to, say, trying to start the EV revolution with lead-acid batteries or the PC revolution with vacuum tubes. While it's technically possible to try, it's just not going to "take."
"The toxic side of the Moon" - https://news.ycombinator.com/item?id=47768039
When life gives you lemons, don't make lemonade
Sounds similar to asbestos.
That’s such a weirdly specific detail but also kinda fascinating. Imagine going to the Moon and the first thing you notice is “huh… smells like gunpowder.
I just had a filling replaced at the dentist yesterday and when he was grinding away at it to shape it, I would get a terrible whiff of something like gunpowder. It was quite disturbing.
But now I can just tell everyone my tooth is filled with moon dust.
Cue Cave Johnson: “The bean counters told me we literally could not afford to buy seven dollars worth of moon rocks, much less seventy million. Bought 'em anyway. Ground 'em up, mixed em into a gel. And guess what? Ground up moon rocks are pure poison. I am deathly ill.”