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A Real-Life Space Botanist Comments On the Potato Garden In 'The Martian' (cnet.com)
MarkWhittington writes: In the hit movie, The Martian, stranded astronaut Mark Watney famously survives on Mars by creating a potato garden using Martian soil mixed in with composted human excrement. According to a story in CNET, NASA believes that the movie is on the right track as far as astronauts growing their own food on long-duration space missions. However, some caveats exists concerning how the film depicted space agriculture.
If you're wondering how Matt Damon eats or breathes, and other science facts.
LALALALA
You should remind yourself it's just a show I should really just relax.
AntiFA: An abbreviation for Anti First Amendment.
I'd be more interested in his take on maritime law.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
btw, that movie ending was terrible. Iron man, really? The book had it right.
"This is where Bruce Bugbee, director of the Plants, Soils & Climate Department at Utah State University, enters the picture."
The guy should really take over the Entomology Department.
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
What is it with these people, that they have to comment how their jobs are represented in movies or tv series.
Did you ever hear a cowboy or lawyer complain?
You routinely mix *real* science and *fiction* in this type of writing.
Every Si-Fi Movie I've seen in my lifetime had assumptions or plot devices which where hopelessly impossible based on known physics. The trick is to make the story engaging enough so that the majority of people reading/watching will suspend their thinking about reality and science and just enjoy the story. My favorite example was "Gravity" where orbital dynamics where simply ignored wholesale, mainly because what would take weeks/months/years to develop in reality, needed to happen on much shorter time frames for the sake of the story. If you liked the movie, I'll bet you didn't notice this the first time you watched it. You suspended scientific reality, and it doesn't really matter. It was a movie...
So, who cares if the scientific reality doesn't quite match the story? Of course it's always interesting when the author is clever enough to keep the impossible technology to a minimum, but let's face it. If it took hours to shuttle down/up from a ship in orbit, decades to get to the next solar system and decades to get a message to/from headquarters the stories would be really slow paced.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
besides, I don't see the guy making specific predictions about what would happen. What someone should do is use the data we have on martial soil to duplicate the setup and see what happens.
Also, I think that the martian light issue isn't a deal. Even in the book, the station would have to be opaque so it is purely a question of whether he had sufficient artificial lighting inside the station. I don't recall if that was a addressed in the book or not but it would have been overly bright and hard to watch so wouldn't be emphasized in the movie.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
I'm very surprised that the producers didn't consult experts with practical experience growing potatoes on Mars. Typical Hollywood bullshit.
The nutrient levels in martian soil are lower than on earth, but they are not zero. With some work, which Damon's character does in the film, it is not inconceivable for someone with sufficient botanical skill to accomplish what he does... (although I do suspect it would take more effort than what the film depicted).
File under 'M' for 'Manic ranting'
It wasn't composted. It was sealed in plastic in a box sitting outside, frozen. He was just growing pooptatoes.
The issue with martian soil as presented in the movie isn't that it doesn't have enough nutrients, it's that it has a lot of poison (perchlorates).
This is a good read:
http://www.space.com/21554-mar...
But those nitpicking details could be crucial in real life.
Biosphere II's numerous points of failure proved that part. Materials used in construction, unanticipated environmental considerations like simple condensation problems or oxidation, and ecological relationships between competing organisms proved too much for the engineers and scientists to anticipate.
Sustainability is a popular subject taught in western public schools and based on similar assumptions to those of other Cartesian reductionist approaches to 'the sciences'. But as the climate skeptics argue, earth's ecology is not static, and it's rate of change fluctuates so that in human generational terms those fluctuations may seem irrelevant to us in the short term. Part of this myopic view is rooted in our relative ignorance and hubristic belief that 'We' can always bail ourselves out of whatever jam the world holds. The latest popular belief system has it that Science! will save us.
Until recently, our world has been large enough to allow us the freedom to splinter into various groups, traveling away from each other and establishing sociopolitical outposts and trying to develop different approaches to living, not that the basic parameters for living have varied all that much. But now that Homo sapiens numbers are (probably) approaching the carrying capacity of the earth and our ecological impact is actually effecting changes to the basic chemical and energetic makeup of the troposphere, we can actually see that ecological management and environmental responsibility are necessary to ensure a healthy relationship within our primary biosphere.
The prospect of attempting to establish and manage a sustainable effort off-planet may actually be more relevant to the long term survival challenges we face right here on good 'ol Terra firma. Let's hope that the lessons we leaned at Biosphere II and during our relatively brief history of experimentation with agriculture, engineering, chemistry and physics allow us the freedom to learn from the inevitable failures we'll encounter outside our own little spaceberg.
captcha=anarchy
We've grown plants in regolith simulant.
So it's not like we don't already know that the answer is "yes".
http://journals.plos.org/ploso...
It's like you didn't even listen to the parent.
Martian regolith contains perchlorates. It's toxic. We're not talking about nutrient levels. It's up to 2% by mass perchlorate ion. Perchlorates are rocket fuel. Literally, they've actually considered harvesting them to make propellant on Mars. They're also quite toxic, impeding thyroid function at a couple dozen parts per million quantity in water. They're toxic to plants too.
You can't just, like in the book, take some martian regolith, take some manure, sprinkle on some dirt for bacteria (which was BTW a pointless step given the crop choice and the bacteria already present in the manure), mix it all together and call it a growth medium. First you have to bake the regolith to break down the perchlorates. Then you have to rinse it to remove the extra salts. Then if you have a reverse osmosis system you could add the water back in. There's still no guarantees then that it'd be fertile/have all of the needed nutrients in approximately the right ratios, but at least it's not guaranteed to be a health hazard to both you and your plants.
"Oh, goodness. Look at my wrist, I have to go." "But what about your clothes?" "I don't love these."
So, how many planets has the so-called "Real-Life Space Botanist" done any work on?
Sounds very theoretical for real-life.
'nuf said.
By the way, how much perchlorate was in the regolith simulant?
The problem with simulations is that they are just that---simulations.
Nutrient deficiency would not be a problem. He had plenty of vitamin tablets. IIRC the potatoes were simply calories.
:-)
And I'm going with the idea that the regolith was processed to remove perchlorate off screen, didn't need to bother viewers with those details.
File under 'M' for 'Manic ranting'
Perchlorates may lead to health problems but likely not deadly. According to some groups, perchlorate affects only the thyroid gland. Because it is neither stored nor metabolized, any effects of perchlorate on the thyroid gland are fully reversible. Some other studies suggest that perchlorate may have pulmonary toxic effects as well. In this article it is mentioned that exposure could be managed. As for using the soil for agriculture, there are several technologies can remove perchlorate, via treatments ex situ and in situ. Ex situ treatments include ion exchange using perchlorate-selective or nitrite-specific resins, bioremediation using packed-bed or fluidized-bed bioreactors, and membrane technologies via electrodialysis and reverse osmosis. In ex situ treatment via ion exchange, contaminants are attracted and adhere to the ion exchange resin because such resins and ions of contaminants have opposite charge. It may be beneficial to process it. Researchers have proposed a biochemical approach for the removal of perchlorate from Martian soil that would not only be energetically cheap and environmentally friendly, but could also be used to obtain oxygen both for human consumption and to fuel surface operations. In any event, precautions will have to be taken but the presence of perchlorates in the soil does not appear to be 'show stopper' at this point.
Today's vices may be tomorrow's virtues.
Right.... and like I said, it would require some work to make happen.
My point being that it's not at all impossible
File under 'M' for 'Manic ranting'
“It's mostly iron oxides. And iron makes stuff red, like rust. So it would be pretty hard to just take soil the way he did in the movie and put a little bit of composted human waste on the plants, and magically grow these great potatoes."
I'm not a botanist, so maybe I need the remedial version, but what does iron making stuff red have to do with any of this? Are there other qualities of Martian soil that would make it bad for growing things besides the red color?
Perhaps in primitive settings human waste was only used to fertilize a field that was being left fallow that year? Perhaps composting was required?
‘Boil it Cook it, Peel it or Forget it’ will do the trick.
Depends on the crop. Low, leafy crops like lettuce are succeptible to rain splatter from the ground. Root crops are also out, for obvious reasons.
Perchlorates weren't a confirmed thing when Weir wrote the novel, I'm fairly sure.
Martian regolith contains perchlorates. It's toxic. We're not talking about nutrient levels. It's up to 2% by mass perchlorate ion..
First you have to bake the regolith to break down the perchlorates. Then you have to rinse it to remove the extra salts. Then if you have a reverse osmosis system you could add the water back in....
From what I read the perchlorate content is 0.5-1.0%, which is still a lot, but there is no need to "high-ball" the estimate. Watney would have known about this quite well, and could very well chosen soil at the low end of the range.
Also the perchlorate removal process could be a lot simpler than you assert. As the article above points out: "Perchlorate salts are very soluble in water...". Simply leaching the soil through his evaporative recovery cycle could remove perchlorates just fine (although the length of time to do this would likely be a problem giving his limited quantity of water).
Your reference to "reverse osmosis" mystifies me. The water is being recovered by simple condensation is quite pure.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
I just want to say, most people have no idea how many plants one must grow in order to survive. If you, 1 adult, want to get most of your calories from a plant, a potato is a decent choice. You can plant 5 kilos of potatoes in a 30 meter row, and expect ~ 90,000 kC. Since they take 90-120 days to mature, in order to have a continuous supply, you'd want maybe twice this many, along with lots of other plants that supply calories, protein, vitamins, and flavor. Two rows of potatoes are about a meter wide, so you're looking at 30-40 m^2. You have to dedicate about 1/25 of your potato crop to seeds, and have a good place to store them. This is also assuming that you are great at growing potatoes, nothing goes wrong, and you plant them every week and harvest them every day.
Due to low light on Mars, you might divide this yield in two. Probably the way it would go is the initial harvests would be smaller until you figured out which varieties yielded more. I'd want 80 m^2 just for potatoes, per person. Then there's all of the other plants. I'd plan on having a 250 m^2 facility, per person, at least.
The movie took lots of liberties and simplified (or eliminated) the detailed explanations in the book. The book did not use plastic and duct tape.
The movie took lots of liberties and simplified (or eliminated) many of the detailed explanations in the book. Don't look at the movie for scientific accuracy; it isn't. The movie is a product of Hollywood after all.
Read the book. It's far more rewarding.