4 ms·

So just plain regolith was used? I wonder if it was augmented by fertilizer how much of a difference it would make (a la The Martian)?

deleted 4y ago
[deleted]
gwill 4y ago
"Each well contained 900 mg of regolith material layered over a 0.45-micron filter and Rockwool wick and was sown with 3-5 Arabidopsis seeds suspended in water" looks like it was as true to the source as possible. wish they had another 12 grams to test with fertilizer.
- lathyrus_long 4y ago
  They applied "nutrient solution of 0.125× strength MS nutrient solution, pH 5.7 (Murashige and Skoog)". The salts in that make a typical complete hydroponic fertilizer. https://en.wikipedia.org/wiki/Murashige_and_Skoog_medium https://en.wikipedia.org/wiki/Murashige_and_Skoog_medium
  - gwill 4y ago
    oh shoot, my bad. if that was in the article i missed it.
kataklasm 4y ago
A few years ago I was writing a (semi-)scientific paper ("Seminarfacharbeit") with two other students as part of the high school graduation process (Abitur) in Germany. The general topic was water and air recycling/purification and plant nurturing for long duration space trips such as a trip to Mars. In the course of writing the paper we had access to a Mars regolith simulant with a very analogous chemical composition to real Mars regolith. We experimented with growing tomatoes, soybeans, radish, spinach and some salad variant I don't remember the name of, each with and without fertilizer. We did'nt have a lot of time and not enough regolith simulant to get significant results, but after a month tomatoes, soybeans and radish showed large growth, with sprout shoots of up to 20cm. We also controlled lighting to be more similar to Mars, although there isn't much difference in daytime lengths. Unfortunately we weren't able to control the atmosphere to be similar to Mars atmosphere, so take our results with a grain of salt.
- tagami 4y ago
  Grain of salt is an interesting comment as most regolith simulants do not include the perchlorates
jillesvangurp 4y ago
I'm guessing that they would have added some simple nutrients and tried with plants you would find in e.g. deserts that are used to grow in very low quality soil. Over time, you could probably make the soil richer simply by supplying simple nutrients and chemicals and letting nature do its thing. The importance of that is that there would be no need to transport many tonnes of earth soil. Though using some of that would probably help bootstrap soil production. Chemical fertilizers are mainly produced using simple chemicals (hydrogen, ammonia, phosphates, etc. So, you could see that happening on e.g. Mars which probably has most of what you'd need in some form. I guess the Moon would be more challenging as it has no atmosphere and lacks elements like nitrogen and carbon.

deleted 4y ago

[deleted]

gwill 4y ago

"Each well contained 900 mg of regolith material layered over a 0.45-micron filter and Rockwool wick and was sown with 3-5 Arabidopsis seeds suspended in water" looks like it was as true to the source as possible. wish they had another 12 grams to test with fertilizer.

lathyrus_long 4y ago
They applied "nutrient solution of 0.125× strength MS nutrient solution, pH 5.7 (Murashige and Skoog)". The salts in that make a typical complete hydroponic fertilizer. https://en.wikipedia.org/wiki/Murashige_and_Skoog_medium https://en.wikipedia.org/wiki/Murashige_and_Skoog_medium
- gwill 4y ago
  oh shoot, my bad. if that was in the article i missed it.

kataklasm 4y ago

A few years ago I was writing a (semi-)scientific paper ("Seminarfacharbeit") with two other students as part of the high school graduation process (Abitur) in Germany. The general topic was water and air recycling/purification and plant nurturing for long duration space trips such as a trip to Mars. In the course of writing the paper we had access to a Mars regolith simulant with a very analogous chemical composition to real Mars regolith. We experimented with growing tomatoes, soybeans, radish, spinach and some salad variant I don't remember the name of, each with and without fertilizer. We did'nt have a lot of time and not enough regolith simulant to get significant results, but after a month tomatoes, soybeans and radish showed large growth, with sprout shoots of up to 20cm. We also controlled lighting to be more similar to Mars, although there isn't much difference in daytime lengths. Unfortunately we weren't able to control the atmosphere to be similar to Mars atmosphere, so take our results with a grain of salt.

tagami 4y ago
Grain of salt is an interesting comment as most regolith simulants do not include the perchlorates

jillesvangurp 4y ago

I'm guessing that they would have added some simple nutrients and tried with plants you would find in e.g. deserts that are used to grow in very low quality soil. Over time, you could probably make the soil richer simply by supplying simple nutrients and chemicals and letting nature do its thing. The importance of that is that there would be no need to transport many tonnes of earth soil. Though using some of that would probably help bootstrap soil production. Chemical fertilizers are mainly produced using simple chemicals (hydrogen, ammonia, phosphates, etc. So, you could see that happening on e.g. Mars which probably has most of what you'd need in some form. I guess the Moon would be more challenging as it has no atmosphere and lacks elements like nitrogen and carbon.