Skip to main content

How did Mark Watney manufacture oxygen in The Martian?


The oxygen level throughout the movie remained at 20%. Why?



Answer



He had a machine called an oxygenator in the Hab. Throughout the book, a lot happens with this machine and it is the reason he has to cut a hole in the top of one of the Rovers to carry it. He brings it with him to the lander (Ares IV) site which explains the oxygen during that long drive and there.


It should be noted that the book focuses a lot on the fact that if you breathe in a sealed environment, you will die of carbon dioxide poisoning long before you can deplete the oxygen. Removal of CO2, therefore, is more important on the whole.


He has a large but limited amount of disposable filters which can trap CO2, and greatly extend the amount of time he can breathe a limited quantity of air. It doesn't replenish oxygen though so he still needs to get oxygen from somewhere.



The oxygenator works by cooling air to very low temperatures and decent pressure. It then separates gases based on their condensation/sublimation temperatures. This is how compressed gases are produced and is probably the most effective way to do it in bulk.


In real-life there are also filtration systems which can separate gasses as gasses (this is often used for putting N2 in bags of chips for example). On the ISS, they perform electrolysis to separate water into oxygen and hydrogen but that would make no sense on Mars as he has very limited water supplies.


Comments

Popular posts from this blog

languages - Do we ever see written English in the Star Wars films?

In Empire Strikes Back , we see a transcription of what R2's beeps and bloops mean, but it's not English (sorry for the low quality, it's from the 2004 DVDs): I'd assume it's what Basic looks like when written, but is there some point in the the Star Wars films we see written English instead? (This sort of spun off from a discussion in How do people understand astromech droids? .) Answer At one point there was English but it has been phased out in subsequent versions of the films. Chris Gould at DVD Active did a comparison of all versions of each of the Star Wars films, and in his comparison of Episode 4 , there are a couple of screenshots showing how the power gauge for the Death Star tractor beam was changed. I imagine there are probably more to be found in his other comparisons but I haven't got around to reading those yet.

Was the "pure soul" of Harry's what had really hurt Voldemort?

In the Order of the Phoenix, Voldemort possesses Harry, and it hurts. Greatly. I think that Dumbledore explained that it was because Voldemort's rotten soul was incapable of assimilating Harry's pure soul, that Voldemort didn't understand the love and friendship etc that Harry has in his heart. But, I think it was a lie. Remember that in Deathly Hallows, while looking for information regarding Horcruxes, it is discovered that it is in fact possible to merge a soul fragment back, but that the process was extremely painful. Now then, if Voldemort tried to possess Harry, and Harry had a fragment of Voldemort's soul, I think that it could have been the true cause of Voldemort's pain: the fact of having his soul so close of another fragment. I think that Dumbledore knew that fact, but had to lie to Harry because it was inappropriate to let him know that he had one of Voldemort's soul fragments at the moment. Is that right? Or was it truly the pure soul of Harry's...

star wars - What "exactly" happens when someone turns to the Dark Side?

When I saw the original Star Wars saga as a kid, the concept of the Dark Side imprinted in me was quite simple. You did a bad thing, so you're a bad person so you go to the Dark Side and keep doing bad things. Now, obviously this doesn't hold true in reality. In my mind it is perfectly reasonable for Luke to kill the Emperor and Vader and then just flee the Death Star and rejoin the Alliance. After all they are at war, those are enemy officers that have captured him and are taunting him by threatening with death of all loved ones and the whole operation was intended to kill the Emperor anyway. The same would hold true for Anakin. He could have killed Mace Windu to save the Chancellor and Padme but that doesn't mean he's going to then go mad and kill all Jedis including children. It doesn't add up from a merely psychological point of view. He had a set of objectives and that made him want to keep the Chancellor alive (quite valid by the way, Mace Windu is quite clums...

star trek - Warning regarding forward saucer section in Nemesis?

In Star Trek: Nemesis , just before the Enterprise rams into the Scimitar, Picard sends a text message from his captain's chair arm pad to Troi — who is manning the helm in lieu of the crewman who was just blown out through what was once the view screen — indicating that she should put full impulse on standby. (Literally, if you watch the scene closely, Troi's console prefaces the order with "TXT MSG" !) My question is: Did Picard also somehow warn crew members in the forward saucer section about what was about to happen? The ramming of the Scimitar was a heat of the moment decision. Considering that he also resorted to calling the auto-destruct sequence shortly after (which ended up being offline), he probably was of the mindset that any losses would be acceptable in order to hault Shinzon's march to Earth. Still, I'm curious. Answer The original script indicates that he called for the crew to " brace for impact ". Whether that call (or the comma...