Propelling a spacecraft to get us to another planet is just one challenge. Another is making sure we have the resources to stay alive on board our spacecraft while we make our way to our destination. Even a visit to a nearby planet would require months of travel. With weight and space at such a premium, how do you determine how much water to bring and how do you manage it?
To say that every drop of water aboard a spacecraft is precious is an understatement. On board the International Space Station there are systems that recycle 93 percent of the water used [source: NASA]. The processes purify water so that it may be used repeatedly, reducing the need to send up more water from Earth.
That means gray water -- the waste water produced after cleaning dishes, clothes or even people -- can be made into drinking water again. But that's not all! Even sweat and, yes, urine are processed. Everything is filtered out and only pure water remains.
The waste water moves into a distiller. The distiller rotates in order to simulate gravity -- otherwise contaminants in the liquid wouldn't separate. Water passes through a filtration system that uses materials like charcoal and chemical compounds to bond with contaminants, letting only the water pass through.
A long space flight won't have the chance to pick up more water along the way. Conserving every drop possible will be a necessity. And some of that technology may even find its way into systems down here on Earth.
Author's Note: 5 Green Technologies for Interplanetary Space Travel
Green technology and interplanetary space travel may seem like a strange combination, but it makes sense. Green technology is all about finding environmentally-friendly and efficient ways to achieve goals. Interplanetary travel by necessity requires efficiency and safety. It's fun to imagine crossing the galaxy in a spaceship kitted out with replicators and holodecks, but it's a safe bet that our early days of space travel will be more about making every effort count.
More Great Links
- Brauenig, Robert. "Rocket Propellants." Rocket and Space Technology. 2008. (March 28, 2012) http://www.braeunig.us/space/propel.htm
- Brumfiel, Geoffrey. "Experts Fuss Over Cost Of Nuclear Fusion Research." NPR. July 27, 2010. (March 27, 2012) http://www.npr.org/templates/story/story.php?storyId=128778289
- Carter, Lynn. "If Mars is only about 35-60 million miles away at close approach, why does it take 6-8 months to get there?" Curious About Astronomy. Cornell University. May 2003. (March 28, 2012) http://curious.astro.cornell.edu/question.php?number=547
- Coffey, Jerry "How Long Does it Take to Get to Mars?" Universe Today. June 4, 2008. (March 28, 2012) http://www.universetoday.com/14841/how-long-does-it-take-to-get-to-mars/
- Environmental Protection Agency. "Hydrazine." January 2000. (March 27, 2012) http://www.epa.gov/ttn/atw/hlthef/hydrazin.html
- Heussner, Ki Mae. " One-Way Mars Mission: Would You Boldly Go?" ABC News. Jan. 13, 2011. (March 28, 2012) http://abcnews.go.com/Technology/mission-mars-boldly/story?id=12607453#.T3THimEV3GF
- Irvine, Dean. "Express lift to the stars." CNN. Dec. 4, 2006. (March 28, 2012) http://edition.cnn.com/2006/TECH/space/09/18/space.elevator/
- Jones, Willie. "A Fusion Thruster for Space Travel." Ieee Spectrum. August 2011. (March 27, 2012) http://spectrum.ieee.org/aerospace/space-flight/a-fusion-thruster-for-space-travel
- LaMonica, Martin. "A reality check on nuclear fusion at MIT." CNET. June 29, 2011. (March 27, 2012) http://news.cnet.com/8301-11128_3-20075206-54/a-reality-check-on-nuclear-fusion-at-mit/
- NASA. "Green Flight Challenge." (March 29, 2012) http://www.nasa.gov/offices/oct/early_stage_innovation/centennial_challenges/general_aviation/index.html
- NASA. "Recycling Water is not Just for Earth Anymore." Nov. 17, 2008. (March 28, 2012) http://www.shermanstravel.com/perfect_trips/American_Southwest
- NASA. "Space Shuttle and International Space Station Frequently Asked Questions." Feb. 24, 2008. (March 28, 2012) http://www.nasa.gov/centers/kennedy/about/information/shuttle_faq.html#14
- NASA. "Water on the Space Station." Nov. 1, 2000. (March 28, 2012) http://science.nasa.gov/science-news/science-at-nasa/2000/ast02nov_1/
- Park, Robert. "Voodoo Science." Oxford University Press: Oxford, U.K. 2000.
- Saeta, Peter N. "What is the current scientific thinking on cold fusion? Is there any possible validity to this phenomenon?" Scientific American. Oct. 21, 1999. (March 28, 2012) http://www.scientificamerican.com/article.cfm?id=what-is-the-current-scien
- Smithsonian. "Apollo 11." National Air and Space Museum. (March 27, 2012) http://www.nasm.si.edu/collections/imagery/apollo/as11/a11facts.htm
- Steitz, David and Newton, Kimberly. "NASA Seeks Proposals for Green Propellant Technology Demonstrations." Feb. 8, 2012. (March 27, 2012) http://www.nasa.gov/home/hqnews/2012/feb/HQ12-046_TDM_Green_Propellant.html
- The Space Elevator Reference. http://spaceelevator.com/
- Wolfram Alpha. "What is the distance between Earth and Mars?" (March 28, 2012) http://www.wolframalpha.com/input/?i=distance+between+earth+and+mars
- Wolfram Alpha. "What is the distance between Earth and Venus?" (March 28, 2012) http://www.wolframalpha.com/input/?i=distance+between+earth+and+venus
Wolfram Alpha. "What was the distance between Earth and the Moon in July, 1969?" (March 28, 2012) http://www.wolframalpha.com/input/?i=distance+between+earth+and+the+moon+july+1969
HowStuffWorks looks at what the cleanest cities are doing to avoid a 'bad air day.'