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Preventing Sick Spaceships
An anonymous reader writes "The official NASA home page has a writeup on one of the lesser-known dangers of living on a Space Station: space germs. 'Picture this: You're one of several astronauts homeward bound after a three-year mission to Mars. Halfway back from the Red Planet, your spacecraft starts suffering intermittent electrical outages. So you remove a little-used service panel to check some wiring. To your unbelieving eyes, floating in midair in the microgravity near the wiring is a shivering, shimmering globule of dirty water larger than a grapefruit. And on the wiring connectors are unmistakable flecks of mold.' The article goes on to describe the unlikely circumstances that form these micro-ecologies, and what astronauts do to deal with the situation."
Does this summary remind anyone else of a certain Voyager episode?
In all seriousness this is an interesting issue I've never heard about before. You'd think the media would be all over this as an actual new space story, it's been so long since anything new was really done (new in the sense of something you'd never think about). This begs the question of whether astronauts and their equipment should be decontaminated before going into space, sure there are microorganisms in their bodies but it would still probably be beneficial.
This also makes me wonder if NASA plans it's airflow so as to avoid situations where air is being blown into an area that the astronauts rarely visit and that is beneficial to bacteria, perhaps air flow could become a big part of space vessel designs so that situations like this are avoided?
All in all an interesting story.
There are two kinds of fool One says 'This is old therefore good' Another says 'This is new therefore better'- Dean Ing
Well not really, but we seem to live best in a natural habitat - city dwellers have higher rates of asthma, there are always cases of sick buildings on the news(bad vents, mold, chemicals), and now fungus eating away at the structure of our space craft. We are really good at building big shiny metal boxes that look like they will stand up to anything, but a little bacteria and the whole thing crumbles. This is a pretty decent justification for 'Leviathan' type spacecraft - partially organic - capable of adapting to organic issues in a way that a metal box just fails.
The rock, the vulture, and the chain
Eight year round trips to Mars are never going to work. Name me one voyage that lasted longer than even one year without having to dock in some fashion.
We will never be able to fully explore, experiment and gather resources in out solar system if trips between planets take 5+ years. We need to look into saner proplusion systems that seperate the ground to orbit engine from the interplanetary engine. Even sci-fi shows seem to have grasped that fact.
May the Maths Be with you!
Before anyone mods me down for trolling consider this: do you really think it would be a good idea for astronauts to exist in a completely sterile enviroment for years on end? What do you think this would do for their immune systems? At the very least they'd be seriously impaired by the time they came back to earth and possibly they could even die of some common microbe that is of no concern to people with healthy immune systems. At the worst their immune system could go into auto immune disease mode and then you could well end up with your spacecraft arriving at mars with just corpses strapped in the seats.
Seems odd that with all that recycling, simple dehumidification would be such a problem. All you need is a cold surface and ventilation across it. Standard dehumidifyers use closed system evaporation to produce this effect, but I bet the hull of the ship on the dark side gets pretty cold. I'm sure it would be easier to take advantage of the existing heat loss, rather than using energy for a compressor.
"Knowledge is the only instrument of production that is not subject to diminishing returns" -Journal of Political Econom
Given the lead-in to the article, wouldn't "How could they cut the power, man? They're animals!" be more appropriate?
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The greatest problem in dealing with air recirculation on a space ship or a space station is the weightlessness. No gravity - no convection. From there on hot and cold pockets are free to form around the place and there is no means to deal with them. Same for local humid pockets, same for condensation. The last is the worst. In the presense of gravity the chilled air will flow away from the cold object and be replaced by new air. Same for water. It will drip somewhere. In weightless conditions it will just sit there and provide nice environment for rust and rot. And evolve. In an accelerated manner under the influence of cosmic radiation. The rumour goes that some of the moulds on Mir around the end of its lifetime could eat plastic (or at least the plastifier out of it).
IMO from one point onwards this problem alone can justify any of the classic "spinning wheel" designs. It may end up cheaper building something big enough to spin it compared to dealing with the environmentals in a medium size station (or ship).
Baker's Law: Misery no longer loves company. Nowadays it insists on it
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Us airplane drivers are very familiar with the phenomena of carburetor ice. Simply running the air through a venturi (or maybe a vortex tube?) will reduce the pressure and temperature sufficiently to dehumidify it. Then you can redirect the fast moving air to "sling" the water out, which carries much more mass, thus momentum, to where ever you wish. I don't know if this has been tried and dismissed as impractical.
What?