Good point about the nitrogen being utilized as fertilizer. I believe in the book he mentioned ammonia, but I can’t remember whether or not he mentioned taking advantage of that in his farming operation.
I am kind of disappointed Watney did not mention seeing deimos and phobos, how they would look to him in the martian sky.
Nitrogen would be plentiful in human waste and is efficiently recycled in natural systems. Part of the whole business with growing and establishing the soil microbiota is establishing a nitrogen cycle. Some bacteria take organic nitrogen from amino acids, urea, and metabolize it to produce ammonia. Other bacteria metabolize ammonia and produce nitrites and nitrates. Denitrification (conversion of nitrates to nitrogen gas) would occur at a negligible rate since it typically only occurs in the absence of oxygen.
Essentially all of the nitrogen that is in the (presumably) high-protein rations will eventually be usable as fertilizer, as long as the water recycling system doesn’t dump all that urea somewhere un-recoverable. And if it does, Whatney can just pee on his compost pile…
That is a lot of shit.
No, wait, I didn’t mean it that way. 
They were seen in the film, however.
True, but remember the only bacteria that Watney has available are his own intestinal and skin flora which are not optimal for producting nitrates in most biologically available form for most plants. The packaged sterilized sewage he recovered and mixed with the Martian regolith will provide a source of nitrates and nitrites along with his own waste, but given the mass of his crop and the protein load that he needs, generating additional nitrogenous fertilizer would assure a healthy and ample crop. Producing ammonia from MMH should be a fairly easy redox reaction.
Stranger
His attitude was to hate Mars for trying to kill him, and fighting back at it. He was not about to appreciate the beauty of the place, because that would start the process of accepting his death.
And in the book, he described navigating by Phobos.
Hrmm. I’m not sure I got that strong of a vibe from him about his feeling toward Mars. In the book and film, he seemed to react to the entire circumstance (and by extension, the planet) as a formidable foe and adversary that he was determined to beat. He certainly had his highs and lows, especially in the book, but always seemed to respect and appreciate where he was stranded, especially when he overcame certain technological roadblocks.
Ahh, right. It’s been over a year since I’ve read it. I think I’ll read it again, especially in light of the movie, I can flesh out my imagination and orientation better.
Thank you, Dr. Freud.
He said as much in the book. Don’t thank me.
Book-Watney also had a sample of Earth soil with a healthy microbial community, into which he gradually mixed in more sewage and Martian soil to allow the soil microbes to proliferate. And potatoes, having a relatively low protein content, aren’t as nitrogen hungry as most crops.
In the spirit of the book, here’s my back-of-the-envelope figures for nitrogen fertilizer needs:
Recommended amount of nitrogen fertilizer is 200 lbs/acre for potatoes, which is probably in excess given that in typical farming most of the nitrogen is lost to runoff. That works out to only be ~500 g for the 25 m^2 hab growing area. If each of the astronauts is eating a high-protein diet with 100 g of protein per day, on balance they’re excreting 16 g of nitrogen every day. From the very start, that’s 6 * 5 *16 = 480 g of nitrogen in all of the sewage recovered from the first five days of the mission. Exactly what is needed for the entire crop of potatoes. And over the medium and long term all the nitrogen in his food and a nontrivial portion from his body will end up as potential fertilizer.
Most (?) of the nitrogen will be urea however, so if that was discarded somewhere irrecoverable by the water recycling system, Watney would definitely benefit from making some fertilizer from a little of the hydrazine. (To nitpick, in the specific scenario where there’s no nitrifying soil bacteria, ammonia isn’t a useful fertilizer. You’d need to make nitrate instead)
I went to see it last week with some of my favorite geeks. I made us a potato feast for dinner after, with Potatoes au Gratin with red peppers and chilis, potato leek soup with roasted shallots and garlic. and cottage pies in potato boats. LOL!
Many people grew mushrooms in their homes or root cellars. They also ate misc plants like grass seeds sprouting by the road. Anything they passed by that might be edible they’d grab it. My Great-Uncle spoke of people dying with their mouths green from trying to eat blades of grass.
I’ve started another thread on this here. It seems to me that the simulation can’t possibly be correct in saying that both Plan 2 and Plan 3 would have the same return time from Mars to Earth. Please switch to that thread to discuss that point, this one is already going in too many directions!
In the book he was supposed to be doing some less than urgent calculations for another project. When the boss takes him to task about neglecting those, Purnell asks to take some vacation time; then he uses the time to concentrate on Hermes.
Are you assuming that they didn’t send another MAV and then delay a bit to let it juice up? Or did I miss a statement to that effect? I don’t remember anything about that. And frankly I doubt the Chinese would have settled for anything less than their astronaut actually landing on Mars. That was pretty much the deal.
IANAMilitaryL, but it’s my understanding that Courts martial rule on the letter of the law. They don’t have the kind of leeway that civilian jurists do. Only the judge has the option of mercy.
A friend of mine went to a Scottish boarding school in which everybody only used last names. She couldn’t bring herself to change it when she married because it was so ingrained. She had a problem adjusting to hearing her first name when she came home that first Summer.
I don’t think anyone on Hermes would have been triable by a court-martial. The mission commander and pilot were former Navy, I think; NASA doesn’t have current-duty military personnel on its missions. Of course, the policy may change in the next 30 years.
Lewis and Martinez were both active-duty, Lewis in the Navy and Martinez in the Air Force ISTR. That’s why they discussed being court-martialed for mutiny. NASA certainly does include active duty personnel on missions.
Sure it does; there are many past and current astronauts who are active duty military seconded to NASA on assignment which is counted as time in rank, and they could be held accountable for any number of transgressions regarding behavior and conduct. However, the NASA missions are under civilian control and unless there was some aspect of a mission that fell under military jurisdiction (e.g. deployment of a surveillance satellite or some other military mission) and so the UCMJ doesn’t apply to failure to adhere to “orders” from a civilian supervisor. They could be charged with violations of NASA protocol and subject to administrative discipline within the authority of NASA (up to being terminated and released back to their parent service), subject to civil suit for damages, and if the behavior was egregeous enough they could be charged by their parent service with conduct unbecoming an officer or similar, but mutiny is not a valid charge.
Practically speaking, all of outer space (above the Karman line) is extraterritorial and it would be new law to try to prosecute anyone for any crime committed in space. It hasn’t been a problem so far, but it’s only a matter of time before someone gets fed up with the food and smell on the ISS…
Stranger
No, one was current Navy and the other current Air Force in the book and I’m pretty sure in the movie too.
They don’t have any problems prosecuting Americans who committed crimes on far away military bases or aboard airliners in flight, do they? I can’t see this being a big issue except perhaps some squabbling over venue, since Federal prosecutors will want to file in a courthouse with judges biased in their favor.
No, I think the problem that may eventually arise is when there is the realistic possibility of someone committing a crime and never coming down to where they may be placed under arrest. If the technology ever exists to build fully independent colonies, and some jerks in the asteroid belt commit some serious crimes and never have to return to earth, what can be done? Any mission to send a vessel with cops onboard to arrest them would be catastrophically expensive and dangerous.