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Study: Potatoes can grow on Mars

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Re: Study: Potatoes can grow on Mars

#62

From the article: "The box mimics the day-night patterns of Mars, as well as its temperature, air pressure and atmospheric composition." Wait, really? They're growing plants in what's practically a vacuum and at subzero temperatures? Really? That seems... stupendously unlikely... to me. Not that I wouldn't love to be wrong, mind. Anyone have a link to actual data? Everything linked to is just press fluff. Update: Act…

On the Cody's Lab YouTube channel, Cody did expose potato plants to Martian atmospheric pressure for short periods of time. Apparently, potato plants can survive a decompression event, so long as you get them back to an Earthlike environment promptly. https://www.youtube.com/watch?v=z8VPvBr4ppU I doubt they could survive extended exposure, though.

So does this mean the environment was only partially simulated? It sounds like we're assuming Martian potatoes will be grown in pressurized environments.

Re: Study: Potatoes can grow on Mars

#65

But how do they simulate Martian gravity?

The box full of potatoes is falling from a great height with a fairly large parachute? That wouldn't really give the potatoes a very long time to demonstrate growth, though.

just enough time for them to think "oh no, not again" really

Re: Study: Potatoes can grow on Mars

#66
post #62

Earlier quoted context omitted.

On the Cody's Lab YouTube channel, Cody did expose potato plants to Martian atmospheric pressure for short periods of time. Apparently, potato plants can survive a decompression event, so long as you get them back to an Earthlike environment promptly. https://www.youtube.com/watch?v=z8VPvBr4ppU I doubt they could survive extended exposure, though.

So does this mean the environment was only partially simulated? It sounds like we're assuming Martian potatoes will be grown in pressurized environments.

Given an inexpensive transparent material with very high tensile strength and resistance to weathering in the Martian environment, I could see a passive pressurization/thermal regulation scheme for greenhouses on the surface of Mars that relies only on, say, a heat source, some valves, and some consumable gasses. I could imagine such schemes using mainly water as an input.

That said, such a material would be asking for a lot. Then, there's also the UV and other radiation to consider.

Re: Study: Potatoes can grow on Mars

#67
post #52

From the article: "The box mimics the day-night patterns of Mars, as well as its temperature, air pressure and atmospheric composition." Wait, really? They're growing plants in what's practically a vacuum and at subzero temperatures? Really? That seems... stupendously unlikely... to me. Not that I wouldn't love to be wrong, mind. Anyone have a link to actual data? Everything linked to is just press fluff. Update: Act…

I ran a similar experiment at home, albeit with a fern rather than potatoes and without simulating martian light. My fern started to perish (and it was a well established plant). The biggest problem I'm facing at the moment is that Mars is extremely nitrogen deficient. https://reprage.com/post/marsarium-9 https://www.reddit.com/r/Colonizemars/comments/5vi52v/inspir...

That reminds me of an Asimov story, "Founding Father", involving ecosystem change on a planet by stranded astronauts.

Re: Study: Potatoes can grow on Mars

#68

Earlier quoted context omitted.

Celsius at least has a family of units that mesh with it precisely. To heat one cubic centimetre of water up 1°C takes 1 Joule. It also essentially weighs 1 gram at normal temperatures. How many BTUs does it take to heat up one cubic foot of water by one degree Fahrenheit?

It takes one BTU to heat one pound of water, one pint, one degree Fahrenheit. The units may be arbitrary, but they still line up.

Yeah, but a pound of water is not a cubic foot. A pint has nothing to do with inches.

Re: Study: Potatoes can grow on Mars

#69
post #8

I think this article is wrong about the temperature. There is little information available but here is the original press release http://cipotato.org/press-room/blog/indicators-show-potatoes... From what I can gather they used soil from some Peruvian desert and increased the CO2 in the chamber. But there is no mention of simulating the -80F night temperatures typical on Mars.

Potatoes, especially sweet potatoes have been cultivated at high altitude for centuries in South America. You are probably right about -60C being too low, but if they provide some shelter potatoes could handle very low overnight temperatures without needing the amount of climate control that other crops would need. Which is one reason why they are looking at this crop.

You may be able to grow potatoes on Mars, but growing them in the Andes doesn't really get you that much closer to Martian conditions.

Average pressure on Mars is about 0.6 kpa which is a trifle less than the pressure at Cusco which is approx 65 kpa pascals. Mt Everest is still about 37 kpa.

I believe you'd have to go about 50km above sea level to hit the average pressure of Mars.

Re: Study: Potatoes can grow on Mars

#70
post #62

Earlier quoted context omitted.

So does this mean the environment was only partially simulated? It sounds like we're assuming Martian potatoes will be grown in pressurized environments.

Given an inexpensive transparent material with very high tensile strength and resistance to weathering in the Martian environment, I could see a passive pressurization/thermal regulation scheme for greenhouses on the surface of Mars that relies only on, say, a heat source, some valves, and some consumable gasses. I could imagine such schemes using mainly water as an input. That said, such a material would be asking f…

Just replace/recycle it regularly.
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