During the flight of STS-126 in 2008, we carried upthree refrigerator-sized pieces of equipment. One was a toilet for the NASAside of space station. There was already one on the Russian side, so this onegave us redundancy. In the past, when the toilet broke, all work had halteduntil we fixed it. No other single piece of equipment fell into this categoryof importance. The oxygen generator could break, and maybe in a day or two wewould fix it; same with the carbon dioxide scrubber. But when the toilet broke—nowthat was serious.
The second piece of equipment we carried up was a smallchemical plant. It contained a distillation apparatus, catalytic reactors,pumps, filters, and plumbing. It was a chemical engineer’s dream. The liquideffluent from the toilet was plumbed to the inlet of this machine.
The third piece of equipment was a new galley. Itsported an injection port for filling our drink bags and rehydratingfreeze-dried food with our choice of hot or room-temperature water. It also hada hot box for warming thermally stabilized meat pouches (canned meat withoutthe can) and a small refrigerator—not for science samples, but for the crew’sfood. The inlet to the galley was plumbed into the outlet of the chemicalplant. This completed what we call our regenerative life support system. Simplyput, what goes out one end is processed, reworked, and put back in the otherend.
Water is an essential ingredient not just for us, butfor all life forms that we recognize. And water is always in short supply on aspacecraft. There may be water shortages in some places on Earth, butspaceflight redefines the meaning of the word “desert.” Closing the water loopwill therefore be essential technology when humans venture away from Earth forlong periods of time. If the toilet fails on a mission to Mars, the crew willrun out of water and die. Earth orbit, where spare parts and engineeringknowledge are close by, is the ideal place to refine this technology andproduce equipment that is truly robust. I call this engineering research; it iscomplementary to scientific research, and is one of the more importantactivities that we conduct on space station.
Nowhere on Earth do we recycle urine using portablemachinery. Not in Antarctica, not on ships at sea, not in our driest deserts.We choose to let Earth do the recycling, not a machine. Our recycling system onspace station is not a one-time demonstration, nor a test of astronauts’ability to handle the “yuck factor.” It’s a day-in, day-out operation, designedas an integral part of the overall spacecraft water balance. With thistechnology, we are truly on the frontier, and we have serial number 001 of acomplex machine. Of course it breaks down—constantly. And of course, we arealways fixing it. Of course there is a steady stream of spare parts arrivingfrom Earth. Any new technology is like this. The first crews arriving at Marswill thank us for our urine-stained hands.
Morning is a time for comfortable habits, and so it ison space station. Each morning I float out (“getting up” is obviously agravity-centric expression) and do my daily routine. I can hear the rumbles ofthe chemical plant. It vibrates the deck rails and gives your feet a massage atthe same time. Then I float over to the galley and make a bag of coffee. Konais one of my favorites; I can feel the caffeine race to my brain and stimulatemy thoughts. It occurs to me that our regenerative life support equipment isreally just a fancy coffee machine. It makes yesterday’s coffee into today’scoffee.
Don’s blog alsoappears at airspacemag.com.