Plants actually use O2 themselves a lot of the time, so we would still need to truck in a whole bunch of that stuff in. Also the amount of plants needed for just a single human is huge. Most plants are rather bad at producing O2. Most of it actually comes from algae living in water, not potted plants. The YouTube channel Joel Creates did an experiment with how much algae you would actually need to breathe. It’s like a lot, a lot a lot really.
Building some place on Mars or even in orbit that such a large amount of algae could happily live is pretty hard. Hell it’s pretty hard on Earth, where you don’t need to worry about temperature and pressure going out of spec or stuff like radiation. These days we do have pretty effective LED grow lights that prevent the whole thing from becoming too hot. From movies people think space is cold, but getting rid of heat is a big problem. With that much light blasting into the water, the temperature rises and the algae will die from that at some point. So radiating away all that heat is a must. On Mars or the Moon this is easier as the surrounding rocks could be used as a heat sink.
The actual real hard part is not just building this, but building it in a way that can support human life for a long time. Systems such as these are chaotic in nature and often suffer from cascade failure modes. If a little thing goes wrong and some of the algae dies, it often cascades into a full failure where all of it dies off. So there would need to be many smaller systems, isolated as much as possible to prevent cascading failures. The system would also need to be modular enough so it would be easy to disconnect a module, completely clean and sterilize it and put it back into use. With staggered phases applied as to not have large swings in output. As these systems would be rather large in scale and have many different complex parts, a high level of automation is required.
And we haven’t even touched on getting all of this constructed somewhere and have it bootstrapped with enough water, with the right stuff in it and none of the wrong stuff. Enough reliable energy and nutrients to feed it all and transport living algae there to kick it all off.
As far as I know nobody has ever gotten close to anything like this on Earth, let alone in space or on a place like the Moon or Mars. It would be a project that rivals the original Moon landings.
It might sound like a simple enough concept and it is how we are currently living on this planet, so it should be possible. However keep in mind our planet has had huge swings in temperatures and atmospheric composition. There were many many times in Earth’s past where humans could not survive the conditions and we evolved here.
Difficult and stupid aren’t the same thing. There aren’t many goals on the same scale of human progress.
The attempt would likely teach us lessons about our own atmosphere and maintaining it. Learning the failure conditions of a biosphere and how to avert disaster seems extremely relevant for the upcoming decades.
OK, let me rephrase, because i’m misrepresenting the book.
Colonizing Mars is extremely, insanely complex and we have no idea how to even start, and there are SO many better places that we need to try first unless we’re just willing to throw away lives (and trillions of dollars). It goes pretty deeply into all the stuff we either don’t know but need to know, or know but can’t fix, and of course there’s all the stuff we don’t know we don’t know. It discusses the insane logistical effort you need just get the bare minimum going, and how it’s not remotely like living there for a year, or colonizing a new country.
Plants actually use O2 themselves a lot of the time, so we would still need to truck in a whole bunch of that stuff in. Also the amount of plants needed for just a single human is huge. Most plants are rather bad at producing O2. Most of it actually comes from algae living in water, not potted plants. The YouTube channel Joel Creates did an experiment with how much algae you would actually need to breathe. It’s like a lot, a lot a lot really. Building some place on Mars or even in orbit that such a large amount of algae could happily live is pretty hard. Hell it’s pretty hard on Earth, where you don’t need to worry about temperature and pressure going out of spec or stuff like radiation. These days we do have pretty effective LED grow lights that prevent the whole thing from becoming too hot. From movies people think space is cold, but getting rid of heat is a big problem. With that much light blasting into the water, the temperature rises and the algae will die from that at some point. So radiating away all that heat is a must. On Mars or the Moon this is easier as the surrounding rocks could be used as a heat sink. The actual real hard part is not just building this, but building it in a way that can support human life for a long time. Systems such as these are chaotic in nature and often suffer from cascade failure modes. If a little thing goes wrong and some of the algae dies, it often cascades into a full failure where all of it dies off. So there would need to be many smaller systems, isolated as much as possible to prevent cascading failures. The system would also need to be modular enough so it would be easy to disconnect a module, completely clean and sterilize it and put it back into use. With staggered phases applied as to not have large swings in output. As these systems would be rather large in scale and have many different complex parts, a high level of automation is required. And we haven’t even touched on getting all of this constructed somewhere and have it bootstrapped with enough water, with the right stuff in it and none of the wrong stuff. Enough reliable energy and nutrients to feed it all and transport living algae there to kick it all off. As far as I know nobody has ever gotten close to anything like this on Earth, let alone in space or on a place like the Moon or Mars. It would be a project that rivals the original Moon landings.
It might sound like a simple enough concept and it is how we are currently living on this planet, so it should be possible. However keep in mind our planet has had huge swings in temperatures and atmospheric composition. There were many many times in Earth’s past where humans could not survive the conditions and we evolved here.
Yup. Trees are basically carbon neutral.
There’s a great book called “A City on Mars” and it’s mostly about stuff like this. Why colonizing mars is absolutely stupid
Difficult and stupid aren’t the same thing. There aren’t many goals on the same scale of human progress.
The attempt would likely teach us lessons about our own atmosphere and maintaining it. Learning the failure conditions of a biosphere and how to avert disaster seems extremely relevant for the upcoming decades.
OK, let me rephrase, because i’m misrepresenting the book.
Colonizing Mars is extremely, insanely complex and we have no idea how to even start, and there are SO many better places that we need to try first unless we’re just willing to throw away lives (and trillions of dollars). It goes pretty deeply into all the stuff we either don’t know but need to know, or know but can’t fix, and of course there’s all the stuff we don’t know we don’t know. It discusses the insane logistical effort you need just get the bare minimum going, and how it’s not remotely like living there for a year, or colonizing a new country.
NASA should let me put a plastic Koi pond on Mars and dump in a ton of algae killer, it’ll cover a hemisphere in a week.