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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."
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.
Or something even simpler learned from the Navy: if you keep the bilges dry and don't allow standing water to form anywhere then you don't get crazy growth--except the slime molds that grow on the inside of the hull due to condensation on the cold steel. For spacecraft this translates into designing your atmospheric systems so that you don't get water droplets anywhere and having your astronauts be able to inspect and clean all enclosed areas completely and regularly. For those who are familiar with Navy terminology: commence field day! For those who aren't it means you get to clean extra hard for an additional 4 hours a week (compared to your normal 1 hour per day cleanup).
If the Navy can keep growth to a minimum under a steam powered water distillation unit (lots of water, lots of microbes, and lots of heat, lots of minerals, and difficult to clean) then astronauts can keep it clean in space.
The way to be sure that you don't get wet is to have the correct ventilation. This is easy to say but complicated to implement. One way is to configure ventilation to pass dehumidifiers and let the dry air be released in the electric compartments and allow it to leak out into the occupants space from where it is collected, cleaned and dehumidified again. On long-term space missions it will be a critical issue to re-circulate all water and not vent it into space.
Another more complex way is to seal off all electronics and use an inert gas in all electronics compartments. However, this is a very complex solution and it will certainly be hard to keep it safe and sound for a mission that will last for years.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
It's not a 'new' space story - not if you are actually familiar with the state-of-the-art, as opposed to feeding at the teat of the mass media. It's a well known issue - NASA was studying it as far back as Skylab. Heck, Michael Collins (yes that Michael Collins) used it as a plot point in his book Mission to Mars back in 1990!
putting them in vacum raises a number of issues
1: EVA doesn't suit tight spaces or fiddly tasks, that means you have to make everything MUCH bigger to allow it to be maintained by EVA than to allow it to be maintained in a habitable atnosphere.
2: EVA is slow, putting on the suits takes a long time and all work done in them is much slower than that same work would be in a habitable atonosphere.
3: EVA is considered risky. Not as risky as takeoff or landing but certainly not something to be done without great care and a lot of planning.
4: vacum is unfriendly to many types of electronic assemblies (though this can be avoided by carefull choice of materials). Its also unfriendly to any pipes carrying liquids or gasses for several reasons including the fact that (assuming the pipes ultimately serve stuff inside the space station) that the relative pressure between inside and outside the pipes will be much higher.
5: vacum-non vacum boundries are a bitch to take wiring through (think a large metal lump with carefully machined brass pins individually incased in glass for insulation embedded in it).
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
Without gravity, lots of things become very difficult to do. A lot more money should be thrown into researching physics and finding out how to control/simulate gravity.