5 ms·

A Primer on Long-Duration Life Support

101 points by zdw 7mo ago

adolph 7mo ago
This is a great read and unironically I want to subscribe to the substack, which is titled "Mars for the Rest of Us." The author is that Ceglowski of Pinboard and occasional space essays at idlewords.com, both of which make this self-recommending for me at least. It's a cliche that space exploration creates discoveries that improve life back here on Earth. In the topics discussed in this essay, water reclamation and waste recycling especially, the future solutions developed I think will lead to improvements for terrestrial living.
buildsjets 7mo ago
A note on their section on fire extinguishing - just about all aerospace fire extinguishing systems use agents with a fluorine based chemistry. Putting out a fire dissociates some of the agent, and in the presence of humidified air it recombines and forms hydroflouric acid, which will eat you from the inside out. So your air scrubbers had best do a good job at removing acid gasses. https://www.researchgate.net/publication/280646417_Acid_gas_hydrogen_fluoride_production_from_Halon_1301_and_alternative_gaseous_fire_suppressants_-_A_Review https://www.researchgate.net/publication/280646417_Acid_gas_...
- XorNot 7mo ago
  It doesn't really eat you though: HF is so small that the problem is it just traverses straight through the skin into your blood and causes fluoridosis. There's been more then a few metallurgy lab deaths because someone spilled a substantial amount of HF on themselves and didn't realize it.
emptybits 7mo ago
"The limiting factor in urine distillation is actually the high level of calcium from disintegrating astronaut bone, a nice example of how problems in space find ways to compound one another." Sobering. One of the many long term effects of life away from Earth.[1] With humanity's future probably (?) driving more of us to leave the planet, I'm glad these things are being studied. Where there's a will, there's a way. [1] "Long-term space missions’ effects on the human organism: what we do know and what requires further research" https://pmc.ncbi.nlm.nih.gov/articles/PMC10896920 https://pmc.ncbi.nlm.nih.gov/articles/PMC10896920
- imglorp 7mo ago
  They mention a botched drug study but I'm curious why that wasn't redone correctly given how many years we've been at this. And growing plants for that matter. Hop to it guys, we have to get this figured out while we have a station.
- PowerElectronix 7mo ago
  They need to come up with either spinning ships or suits that compress you enough to activate the bones (they are piezoelectric so they naturally catch calcium ions when under stress).
- sans_souse 7mo ago
  > With humanity's future probably (?) driving more of us to leave the planet, I'm I'm seeing it's becoming ever-clearer that our best and possibly only real "option" is here on Earth. That means not fixing our mess = no future.
isoprophlex 7mo ago
On water reclamation: > On the Mir space station, this used to happen organically. Collecting water was a grubby job that involved chasing beach-ball sized spheres of condensate around the colder parts of the spacecraft with trash bags before they could climb into the walls and cause mayhem. Crew members spent three to four hours a day on this dirty and difficult task. That sounds, frankly, horrible. It made me think that the average space module probably smells like moist, reheated ass, too.
- malfist 7mo ago
  Mir famously stank. Though you'd be glad to know without gravity your nose doesn't work as well
- correnos 7mo ago
  Yep! There was a submariner-turned-astronaut that mentioned the smell was pretty similar, and also that submarine deployments can be described as "breathing recycled farts for six months." At least submarines have replacement oxygen handy!
oersted 7mo ago
Curious that both average inputs and outputs match to exactly 5.74 kg. I had intuitively assumed there would be a significant difference, but I suppose that even if a lot of energy is extracted, the mass difference will be negligible, mc2 and all. I'm also surprised that the vast majority of the output carbon is in the form of CO2 rather than feces. It's all rather obvious in retrospect, it was just nice to see crystallized like this.
- birdsongs 7mo ago
  > I'm also surprised that the vast majority of the output carbon is in the form of CO2 rather than feces. Not sure if you know, but in the same vein, I was shocked when I learned ~50% of the biomass of trees is carbon (right, we knew that), but also that the carbon came from CO2 the tree respirated. Also makes total sense in hindsight, but still think it's so cool. The trees literally build their mass from the air and sunlight (and yes, obviously also water and trace minerals from the roots).
  - adolph 7mo ago
    There is a nice Feynman children's lecture about this [0] from the series "Fun to Imagine" [1] 0. https://www.youtube.com/watch?v=ITpDrdtGAmo https://www.youtube.com/watch?v=ITpDrdtGAmo 1. https://www.bbc.co.uk/programmes/p0198zc1 https://www.bbc.co.uk/programmes/p0198zc1
  - geoffschmidt 7mo ago
    And when you set them on fire, it lets the air and sunlight back out!
billfor 7mo ago
The most interesting thing I learned is that we let people who need Zoloft on the ISS. The FAA will disqualify you for that unless you jump through hoops.
- mordechai9000 7mo ago
  My guess is they stock it in case someone needs it during the mission. Not that they are sending people who are already taking it.
  - billfor 7mo ago
    If somebody needed it during a mission it would take at least 2 weeks to take effect. Those drugs are not usually prescribed for acute mental issues.
    - DennisP 7mo ago
      People typically stay on the ISS for six months.
jp57 7mo ago
Haven't many of the non-zero-g challenges been at least partly solved on nuclear submarines, that carry large crews and stay submerged for months at time? Of course there are more challenges, but you do have people living in a pressure canister for long periods.
- siruwastaken 7mo ago
  I think the difference is largely due to the fact that bringing a bit of extra weight isn't as problematic in a submarine as it is in a spacecraft. For example, you always have a water source that can give you oxygen and you don't have to worry about discarding the byproducts.
torben-friis 7mo ago
>and 1.8 kilos of dried food a day to stay alive. Isn't that a lot? A stick of bread is 0.25kg, burger patties no more than 0.2kg, and so on.
- WorkerBee28474 7mo ago
  1.8kg of common food is 5000 Calories-ish. I can only imagine that dried food is more calories per weight. So yeah, a lot.
Panzerschrek 7mo ago
A lot of problems mentioned in the article are solvable by adding more mass - for supplies and spare parts. New generation reusable rockets can allow this. In the past it was costly to launch a rocket, so systems were designed to be compact, but complex/fragile. Cheap space access changes this equation.

101 points by zdw 7mo ago

This is a great read and unironically I want to subscribe to the substack, which is titled "Mars for the Rest of Us." The author is that Ceglowski of Pinboard and occasional space essays at idlewords.com, both of which make this self-recommending for me at least. It's a cliche that space exploration creates discoveries that improve life back here on Earth. In the topics discussed in this essay, water reclamation and waste recycling especially, the future solutions developed I think will lead to improvements for terrestrial living.

buildsjets 7mo ago

A note on their section on fire extinguishing - just about all aerospace fire extinguishing systems use agents with a fluorine based chemistry. Putting out a fire dissociates some of the agent, and in the presence of humidified air it recombines and forms hydroflouric acid, which will eat you from the inside out. So your air scrubbers had best do a good job at removing acid gasses. https://www.researchgate.net/publication/280646417_Acid_gas_hydrogen_fluoride_production_from_Halon_1301_and_alternative_gaseous_fire_suppressants_-_A_Review https://www.researchgate.net/publication/280646417_Acid_gas_...

XorNot 7mo ago
It doesn't really eat you though: HF is so small that the problem is it just traverses straight through the skin into your blood and causes fluoridosis. There's been more then a few metallurgy lab deaths because someone spilled a substantial amount of HF on themselves and didn't realize it.

emptybits 7mo ago

"The limiting factor in urine distillation is actually the high level of calcium from disintegrating astronaut bone, a nice example of how problems in space find ways to compound one another." Sobering. One of the many long term effects of life away from Earth.[1] With humanity's future probably (?) driving more of us to leave the planet, I'm glad these things are being studied. Where there's a will, there's a way. [1] "Long-term space missions’ effects on the human organism: what we do know and what requires further research" https://pmc.ncbi.nlm.nih.gov/articles/PMC10896920 https://pmc.ncbi.nlm.nih.gov/articles/PMC10896920

imglorp 7mo ago
They mention a botched drug study but I'm curious why that wasn't redone correctly given how many years we've been at this. And growing plants for that matter. Hop to it guys, we have to get this figured out while we have a station.
PowerElectronix 7mo ago
They need to come up with either spinning ships or suits that compress you enough to activate the bones (they are piezoelectric so they naturally catch calcium ions when under stress).
sans_souse 7mo ago
> With humanity's future probably (?) driving more of us to leave the planet, I'm I'm seeing it's becoming ever-clearer that our best and possibly only real "option" is here on Earth. That means not fixing our mess = no future.

isoprophlex 7mo ago

On water reclamation: > On the Mir space station, this used to happen organically. Collecting water was a grubby job that involved chasing beach-ball sized spheres of condensate around the colder parts of the spacecraft with trash bags before they could climb into the walls and cause mayhem. Crew members spent three to four hours a day on this dirty and difficult task. That sounds, frankly, horrible. It made me think that the average space module probably smells like moist, reheated ass, too.

malfist 7mo ago
Mir famously stank. Though you'd be glad to know without gravity your nose doesn't work as well
correnos 7mo ago
Yep! There was a submariner-turned-astronaut that mentioned the smell was pretty similar, and also that submarine deployments can be described as "breathing recycled farts for six months." At least submarines have replacement oxygen handy!

oersted 7mo ago

Curious that both average inputs and outputs match to exactly 5.74 kg. I had intuitively assumed there would be a significant difference, but I suppose that even if a lot of energy is extracted, the mass difference will be negligible, mc2 and all. I'm also surprised that the vast majority of the output carbon is in the form of CO2 rather than feces. It's all rather obvious in retrospect, it was just nice to see crystallized like this.

birdsongs 7mo ago
> I'm also surprised that the vast majority of the output carbon is in the form of CO2 rather than feces. Not sure if you know, but in the same vein, I was shocked when I learned ~50% of the biomass of trees is carbon (right, we knew that), but also that the carbon came from CO2 the tree respirated. Also makes total sense in hindsight, but still think it's so cool. The trees literally build their mass from the air and sunlight (and yes, obviously also water and trace minerals from the roots).
- adolph 7mo ago
  There is a nice Feynman children's lecture about this [0] from the series "Fun to Imagine" [1] 0. https://www.youtube.com/watch?v=ITpDrdtGAmo https://www.youtube.com/watch?v=ITpDrdtGAmo 1. https://www.bbc.co.uk/programmes/p0198zc1 https://www.bbc.co.uk/programmes/p0198zc1
- geoffschmidt 7mo ago
  And when you set them on fire, it lets the air and sunlight back out!

billfor 7mo ago

The most interesting thing I learned is that we let people who need Zoloft on the ISS. The FAA will disqualify you for that unless you jump through hoops.

mordechai9000 7mo ago
My guess is they stock it in case someone needs it during the mission. Not that they are sending people who are already taking it.
- billfor 7mo ago
  If somebody needed it during a mission it would take at least 2 weeks to take effect. Those drugs are not usually prescribed for acute mental issues.
  - DennisP 7mo ago
    People typically stay on the ISS for six months.

jp57 7mo ago

Haven't many of the non-zero-g challenges been at least partly solved on nuclear submarines, that carry large crews and stay submerged for months at time? Of course there are more challenges, but you do have people living in a pressure canister for long periods.

siruwastaken 7mo ago
I think the difference is largely due to the fact that bringing a bit of extra weight isn't as problematic in a submarine as it is in a spacecraft. For example, you always have a water source that can give you oxygen and you don't have to worry about discarding the byproducts.

torben-friis 7mo ago

>and 1.8 kilos of dried food a day to stay alive. Isn't that a lot? A stick of bread is 0.25kg, burger patties no more than 0.2kg, and so on.

WorkerBee28474 7mo ago
1.8kg of common food is 5000 Calories-ish. I can only imagine that dried food is more calories per weight. So yeah, a lot.

Panzerschrek 7mo ago

A lot of problems mentioned in the article are solvable by adding more mass - for supplies and spare parts. New generation reusable rockets can allow this. In the past it was costly to launch a rocket, so systems were designed to be compact, but complex/fragile. Cheap space access changes this equation.