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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.
btw, that movie ending was terrible. Iron man, really? The book had it right.
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.
That is not just a show. Too many people want to watch that movie because it's almost scientifically accurate, well, accurate enough that one can make a point in discussing any minor mistake.
Linux is for people who don't mind RTFM.
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's scientifically accurate in that "it's possible to grow plants on Mars, just not in the way done in the movie and certainly not in the way done in the book".
As for the way done in the movie:
Not to mention that the room, as shown in the movie, can easily be calculated to be significantly too small even if it was getting Earth light. But at least the situation in the movie (one order of magnitude too little energy to sustain a person) is better than in the book where potatoes are being grown on normal room lights ;) Most people don't realize how much vastly dimmer it is, from an energy perspective, inside than outside - our eyes compensate for it, otherwise you wouldn't be able to see details in bright areas and dim areas at once. But that little "nitpicking detail" - 2-4 orders of magnitude too little light, give or take - is indeed critical to plants growing, and especially to them producing energy to store that humans can eat.
Had Weir had any experience whatsoever with growing caloric plants indoors, he would have realized this and there are many things he could have done in his design to ensure that the plants would get enough sun. The best option is exactly what the actual botanist above mentions: solar concentrators. A solar thermal power plant is a perfectly plausible way to generate electricity on Mars and Watney - had he been given a solar thermal farm and habitat with lots of transparent plastic - could have redirected heliostats to reflect large amounts of light into the habitat and stripped off insulation (adding it back on every night) to compensate for the dramatically increased heat load. That would have thus avoided the solar to electricity losses and the electricity to light losses, giving an order of magnitude more power, as well as avoiding the need to have quantities of lights onboard hundreds of times brighter (and correspondingly more power-hungry) than you actually would ever find. And it's plausible he could have taken existing heliostats and aluminum scrap and significantly boosted their parabolic area and thus light output (assuming the drive mechanism could take the additional load or he could modify it to).
But, that's not how it went.
There's tons of other things that would have killed the plants grown as described in the book (getting caloric crops to grow right in sealed spaces indoors is difficult even in controlled circumstances, there's such a huge range of things that can suddenly and dramatically wipe them out - which is why, as mentioned in TFA, NASA has a whole department researching the topic to try to create the controlled conditions to prevent this), but let's just stick to the most fundamental aspects here for now. The light was, pardon the pun, the most glaring problem. ;)
"Oh, goodness. Look at my wrist, I have to go." "But what about your clothes?" "I don't love these."
Unlike a lot of other "science fiction" books/stories, Andy Weir seemed to make a genuine effort to get as much right as possible, and did his best to drag along the film producer. If all of science fiction was at this level, it would be a miracle. And as you've pointed out, where the science does fail, it fails in such a way as to spark discussion and interest in the real science. I don't feel like my intelligence was insulted after having watched/read it, or that errors and omissions were a result of laziness or "the audience is too dumb/doesn't care anyway, so why bother". (Although the book was better than the movie in that regard.) If anything it served as a launching (punnnns) point for learning more about growing food on Mars and other similar problems.
The truth is somewhere in the middle.
I'd argue that the film still qualifies as the first mainstream Science Fiction movie. They made a real effort to get the details right, to the point where (at least for the film version), it's reasonable suspension of disbelief, rather then the usual "fantasy movie with spaceships and explosions".
I like your idea about the heliostats, and that could have added more challenges, as he's now taking a big hit to his available electric power. It will be interesting to see what NASA comes up with to do this on purpose. I've been in a house that uses "light pipes" to collectors on the roof for daytime lighting, and that works quite well. Concentrating light from a suitable large collection area into the room sure seems like it would work. Of course you have to be careful to keep it stable in a windstorm, so a bunch of lightweight panels sticking up from the roof of a lightweight structure is asking for trouble, but with fiber optics you'd have more options.
Farming is never a sure thing, but at least you'd be free of insects.
Socialism: a lie told by totalitarians and believed by fools.
Well not exactly. In the book explains that the HAB had excellent CO2->O2 converters. Mars Atmosphere is 95% CO2. It just requires energy, which comes from solar panels. So he had near infinite O2.
-spoilers-
The chemical conversion he does involved turning O2 and Hydrogen into H2O, which basically just involves burning Hydrogen. But burning hydrogen is very dangerous, so he puts on his spacesuit and empties the room of all the O2 (which requires a good bit of tricking the computer system). And slowing feeding the system just enough O2 and H to burn into water.
Unfortunately he forgot that his spacesuit slowly leaks out O2 when he breaths out. So the room slowly filled with O2 until it reached a critical point and the entire room exploded. Much bigger explosion than in the movie apparently.