Chuck Darwin on Nostr: Mars’s surface has perchlorate concentrations of about 0.5% by weight. On Earth, ...
Mars’s surface has perchlorate concentrations of about 0.5% by weight.
On Earth, the concentration is often a millionth that amount.
For NASA, that’s a devastating issue.
The ultimate goal of the agency’s Artemis program is to land astronauts on Mars.
And for the last decade, the agency has pursued a long-term plan of establishing an “Earth independent” human presence on the Red Planet.
More ambitiously, if less plausibly, Elon Musk, the chief executive officer of SpaceX, has stated that he expects a million people to live on Mars in the next 20 years.
Any notion of an independent Mars means the perchlorate problem must be solved, because humans have to eat.
Resupply missions are, by definition, Earth dependent, and hydroponics are inadequate for feeding people in large numbers.
“We can sustain crews of 10, maybe 20, very comfortably with hydroponics,
but it doesn’t scale much larger than that,” says Rafael Loureiro,
an associate professor at Winston-Salem State University who specializes in plant stress physiology.
Hydroponics systems must be built on Earth, and they require energy-inefficient pumps and constant monitoring for bacterial and fungal infections.
“Once the system is infected, you lose your entire crop, because it’s a closed-loop system,” he says. “You have to discard everything and reset.”
The only real path forward, says Loureiro, is farming the land: “The perchlorate problem is something that we will inevitably have to deal with.”
There is no soil on Mars. Just dusty, poisonous regolith—the mixture of loose rock, sand, and dust that makes up the planetary surface.
On Earth, the regolith is replete with billions of years’ worth of broken-down organic biomass—soil—that just doesn’t exist on Mars.
To grow food there, we can’t just drop seeds in the ground and add water. We will need to create a layer of soil that can support life.
And to do that, we first have to get rid of those toxic salts.
There’s more than one way to remove perchlorates.
You can burn them out; the compounds break down around 750 °F, but for that, you’ll likely need power sources like nuclear reactors, and a lot of ancillary equipment.
You can literally wash the perchlorates from the regolith, but, Loureiro explains, “the amount of water that you need to do that is ungodly, and water is a limited resource as far as we know.”
That process would likewise take a significant amount of energy. “That’s something that’s not feasible long term,” he tells me.
The ideal solution is not something dependent on heavy machinery.
Rather, it would rely on something small—microscopic, in fact.
NASA and the National Science Foundation are funding research into how future astronauts on Mars might use microbial life not only to remove perchlorates from the planet’s dirt,
but also to shape and enrich the regolith into arable soil.
The work builds on years of effort to do the same thing in different places on Earth, and if successful, it will improve farming on two planets for the price of one.
https://www.technologyreview.com/2024/10/17/1105135/mars-farming-soil-food-humans-farming-agriculture/
On Earth, the concentration is often a millionth that amount.
For NASA, that’s a devastating issue.
The ultimate goal of the agency’s Artemis program is to land astronauts on Mars.
And for the last decade, the agency has pursued a long-term plan of establishing an “Earth independent” human presence on the Red Planet.
More ambitiously, if less plausibly, Elon Musk, the chief executive officer of SpaceX, has stated that he expects a million people to live on Mars in the next 20 years.
Any notion of an independent Mars means the perchlorate problem must be solved, because humans have to eat.
Resupply missions are, by definition, Earth dependent, and hydroponics are inadequate for feeding people in large numbers.
“We can sustain crews of 10, maybe 20, very comfortably with hydroponics,
but it doesn’t scale much larger than that,” says Rafael Loureiro,
an associate professor at Winston-Salem State University who specializes in plant stress physiology.
Hydroponics systems must be built on Earth, and they require energy-inefficient pumps and constant monitoring for bacterial and fungal infections.
“Once the system is infected, you lose your entire crop, because it’s a closed-loop system,” he says. “You have to discard everything and reset.”
The only real path forward, says Loureiro, is farming the land: “The perchlorate problem is something that we will inevitably have to deal with.”
There is no soil on Mars. Just dusty, poisonous regolith—the mixture of loose rock, sand, and dust that makes up the planetary surface.
On Earth, the regolith is replete with billions of years’ worth of broken-down organic biomass—soil—that just doesn’t exist on Mars.
To grow food there, we can’t just drop seeds in the ground and add water. We will need to create a layer of soil that can support life.
And to do that, we first have to get rid of those toxic salts.
There’s more than one way to remove perchlorates.
You can burn them out; the compounds break down around 750 °F, but for that, you’ll likely need power sources like nuclear reactors, and a lot of ancillary equipment.
You can literally wash the perchlorates from the regolith, but, Loureiro explains, “the amount of water that you need to do that is ungodly, and water is a limited resource as far as we know.”
That process would likewise take a significant amount of energy. “That’s something that’s not feasible long term,” he tells me.
The ideal solution is not something dependent on heavy machinery.
Rather, it would rely on something small—microscopic, in fact.
NASA and the National Science Foundation are funding research into how future astronauts on Mars might use microbial life not only to remove perchlorates from the planet’s dirt,
but also to shape and enrich the regolith into arable soil.
The work builds on years of effort to do the same thing in different places on Earth, and if successful, it will improve farming on two planets for the price of one.
https://www.technologyreview.com/2024/10/17/1105135/mars-farming-soil-food-humans-farming-agriculture/