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.
I read it in Buzz Aldrin's book. He mentioned getting rid of all the samples if that happened. I would think the bigger problem would be moon dust all over their suits, but he didn't describe a plan for that.
He said they thought the odds of that happening were remote though, so I guess they decided to risk it with the suits. Apparently he mentioned the problem to his dad who accidentally told a reporter sitting next to him on a flight leading to a big media cycle about "flaming moon dust" prior to the mission.
Throw all their samples back outside, then very carefully sweep the inside of the LEM and throw the broom & dustpan out too?
In theory, they could have been equipped to partially pressurize the cabin with (say) helium - which would allow some sort of vacuum cleaner to work. But that could have added a fair bit of mass (by the LEM's very tight mass budget standards).
This sort of scenario, which was thought too improbable to plan for, even by an organization as psychotically obsessed with astronaut safety as NASA, is exactly why human spaceflight was important for exploration. Because astronauts could improvise a sensible solution and the tech couldn't.
But you could pour water at the fire from across the room!
Lower gravity is giving the defender an advantage over the elements... at least until it gets low enough for things to start floating, when this flips around. In microgravity, water turns into floating blobs, but fire turns into actual floating fireballs.
Water blobs vs. fireballs. Pretty sure there's a nice videogame idea hiding in there somewhere.
Improvise. Adapt. Overcome or perish. One of the first man in orbit almost died because his suit couldnt fold its arms in vacuum. The enterprise moment where you encounter something new and unforseen must be scary as fuck.
Oxygen if the third most abundant element in the universe.[1]
The Moon minerals contain plenty of it:
The finer regolith, the lunar soil of silicon dioxide glass.[2]
Minerals forming the lunar crust are made up of oxygen, silicon, magnesium, iron, calcium, and aluminum, along with small amounts of titanium, uranium, thorium, potassium, and hydrogen.[3]
I figure you mean free oxygen or diatomic oxygen O₂, but that stuff is rare in the universe, as it’s quite reactive, and largely irrelevant for asteroid impact chemistry extreme heat and pressure, plenty of oxygen available in the rocks smashing together.
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 detail that kills me is moon dust has never contacted oxygen in billions of years, so every time an astronaut came back inside they were essentially doing a chemistry experiment for the first time. the whole moon is just waiting to react with air
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.
> 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.
I work with industrial vacuum machinery and the big slow down in a vacuum system is coaxing out water vapor which sticks to chamber and plumbing walls like glue. My guess is dissolved oxygen in the water vapor or the water vapor itself reacting with dust particles.
Outer space smells like burnt flesh is what I've heard. Space is full of toxic polycyclic aromatic hydrocarbons which are created in novae and are everywhere in outer space in small amounts. They're the same chemicals that generate when organic compounds and fossil fuels are burnt.
Makes me wonder even more why some people really want to go and live there.
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.
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.
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.”
Anyone expecting to colonize Mars, or even send humans there, within the next 1,000 years is going to be sorely disappointed.
I told my neighbor: we could send some humans to Mars, but not expect to get them back!
Even if Mars were pre-terraformed, even if Mars were a perfect idyllic copy of Earth and a Garden of Eden just inviting humans to go there and set up bases, we could not send crews to Mars.
The final nail in this coffin was, for me, when I heard an ISS Expedition astronaut explain what NASA prohibits when they return from a long stretch on the Space Station. The astronauts are not permitted to jog or lift weights. They can't drive a vehicle or fly aircraft(!) They mustn't jump or twist their head around too fast. They must re-learn how to brush their teeth and how to drink fluids. They may feel dizzy, nauseous, or have trouble with spatial judgement. They are, essentially, helpless toddlers confined to their quarters. I mean, it is quite obvious by the way that they must drag these national heroes onto a gurney from the capsule after splash-down that their physiques are no longer normal.
The astronauts experience a lot of muscle atrophy and unique procedures in microgravity. If an astronaut can't even jog, or pass a roadside sobriety test, or go to the bathroom for themselves after an ISS mission, how, after 6 months' travel in deep space, will they accomplish anything at a Mars base, even mere survival?
Surely we could send up all supplies with autonomous vessels. Pre-stock water tanks and oxygen and air and have robots build a basic Mars-base there, before any astronaut arrives. But if the actual journey is practically incapacitating our actual human beings, the whole deal is off.
So no, we'll never get to Mars in the way that Musk and NASA promise. We'll keep sending robots eager to find out more and explore the interesting parts. The robots can bring back all the samples they want. They'll send pictures and even audio and plenty of sensor data. But humans will be lucky if we get a stable colony on the Moon (I believe that Moon Bases have their own currently insurmountable obstacles.) I think that humankind should be really happy and satisfied that we've got orbital space stations with continuous habitation now.
"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
It wasn't just lunar dust, all(?) the crews also reported smelling burning in the tunnel (tunnel connecting CM and LM), might be something to do with the docking latches
Terraforming Luna or Mars is a stupid idea due to their toxic dust. It would be a lot easier to just mine them and construct a rotating habitat in space. The space mission I want to see is one that brings out a container full of rocks from the planetary body back to Earth or to a space station for processing and construction.
To be fair, considering that there are minerals in the Moon that don't exist on Earth, it's normal that the human body experiments an allergic reaction to a set of substances that it hasn't ever been exposed to during thousands of years of evolution.
So a risk somewhat similar to diatomaceous earth and asbestos. A risk that might need to be mitigated should Moon habitation/occupation make financial sense.
Moon dust is really nasty and actually a bigger problem for astronauts and equipment than radiation which can simply be avoided by settling in magma tunnels.
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.
This sounds as if walking on the moon led to some symptoms. But if you know Chris Hadfield, he said "space has a rusty burn smell" even elsewhere. How can they conclude that moonwalking specifically led to what was described? The article has "The toxic side of the Moon", but IMO it would be more reasonable to assume that space in general is toxic, not "only" the moon. It also means that the space suits are not well-equipped - people in 50 years from now will shake their heads about that, how naive we may have been.
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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.
He said they thought the odds of that happening were remote though, so I guess they decided to risk it with the suits. Apparently he mentioned the problem to his dad who accidentally told a reporter sitting next to him on a flight leading to a big media cycle about "flaming moon dust" prior to the mission.
In theory, they could have been equipped to partially pressurize the cabin with (say) helium - which would allow some sort of vacuum cleaner to work. But that could have added a fair bit of mass (by the LEM's very tight mass budget standards).
Lower gravity is giving the defender an advantage over the elements... at least until it gets low enough for things to start floating, when this flips around. In microgravity, water turns into floating blobs, but fire turns into actual floating fireballs.
Water blobs vs. fireballs. Pretty sure there's a nice videogame idea hiding in there somewhere.
> Water blobs vs. fireballs. Pretty sure there's a nice videogame idea hiding in there somewhere.
I like the way you think. :)
The Moon minerals contain plenty of it:
The finer regolith, the lunar soil of silicon dioxide glass.[2]
Minerals forming the lunar crust are made up of oxygen, silicon, magnesium, iron, calcium, and aluminum, along with small amounts of titanium, uranium, thorium, potassium, and hydrogen.[3]
I figure you mean free oxygen or diatomic oxygen O₂, but that stuff is rare in the universe, as it’s quite reactive, and largely irrelevant for asteroid impact chemistry extreme heat and pressure, plenty of oxygen available in the rocks smashing together.
1. https://en.wikipedia.org/wiki/Oxygen
2. https://en.wikipedia.org/wiki/Moon
3. https://science.nasa.gov/moon/composition/
> 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.
I work with industrial vacuum machinery and the big slow down in a vacuum system is coaxing out water vapor which sticks to chamber and plumbing walls like glue. My guess is dissolved oxygen in the water vapor or the water vapor itself reacting with dust particles.
Makes me wonder even more why some people really want to go and live there.
https://en.wikipedia.org/wiki/Perchlorate#On_Mars
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
It seems to be under-reported that the Earth is pretty nice.
> Fine like powder, but sharp like glass
Sounds scary. But totally worth it!
[1] https://www.nasa.gov/image-article/nasas-dust-shield-success...
I told my neighbor: we could send some humans to Mars, but not expect to get them back!
Even if Mars were pre-terraformed, even if Mars were a perfect idyllic copy of Earth and a Garden of Eden just inviting humans to go there and set up bases, we could not send crews to Mars.
The final nail in this coffin was, for me, when I heard an ISS Expedition astronaut explain what NASA prohibits when they return from a long stretch on the Space Station. The astronauts are not permitted to jog or lift weights. They can't drive a vehicle or fly aircraft(!) They mustn't jump or twist their head around too fast. They must re-learn how to brush their teeth and how to drink fluids. They may feel dizzy, nauseous, or have trouble with spatial judgement. They are, essentially, helpless toddlers confined to their quarters. I mean, it is quite obvious by the way that they must drag these national heroes onto a gurney from the capsule after splash-down that their physiques are no longer normal.
The astronauts experience a lot of muscle atrophy and unique procedures in microgravity. If an astronaut can't even jog, or pass a roadside sobriety test, or go to the bathroom for themselves after an ISS mission, how, after 6 months' travel in deep space, will they accomplish anything at a Mars base, even mere survival?
Surely we could send up all supplies with autonomous vessels. Pre-stock water tanks and oxygen and air and have robots build a basic Mars-base there, before any astronaut arrives. But if the actual journey is practically incapacitating our actual human beings, the whole deal is off.
So no, we'll never get to Mars in the way that Musk and NASA promise. We'll keep sending robots eager to find out more and explore the interesting parts. The robots can bring back all the samples they want. They'll send pictures and even audio and plenty of sensor data. But humans will be lucky if we get a stable colony on the Moon (I believe that Moon Bases have their own currently insurmountable obstacles.) I think that humankind should be really happy and satisfied that we've got orbital space stations with continuous habitation now.
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/