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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.
It wasn't composted. It was sealed in plastic in a box sitting outside, frozen. He was just growing pooptatoes.
I'm very surprised that the producers didn't consult experts with practical experience growing potatoes on Mars. Typical Hollywood bullshit.
I'll tell them to post their technical questions on slashdot next time.
Well, they tried, but I was in the middle of delivering manure to the site, and didn't get back to them in time.
Sig ?
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.
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.
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
Also, 450kg of potatoes would lock up ~360L of water, and I expect that the plants would have maybe another 100L in foliage.
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.