Journey to Red Planet may need green thumb
Space travel now, even going to the moon, is like a camping trip, says University of Illinois Professor Luis Rodriguez.
You pack up food, water, oxygen and everything else you need and take it along with you.
If you're on the space station, you might get supplies from a space shuttle periodically, or a care package in the form of a Soyuz capsule from Russia.
You don't have to grow your own tomatoes.
But astronauts on a trip to Mars, something the Bush administration envisions happening in the next 25 years, may need a green thumb.
Rodriguez, a UI agricultural and biological engineering professor, is one of the scientists working with NASA to figure out how a Mars mission could grow at least some of its own food for what likely would be a three-year round trip. It takes six months to get to the Red Planet and another two years for the Earth and Mars to align again for the six-month trip back.
In addition to gardening in space, Rodriguez and colleagues are studying water- and waste-recycling systems designed to reuse, well, pretty much everything. A four- to six-person Mars crew would likely need to turn its wastewater back into potable drinking water.
Some of the technology also should be of use in static moon or Mars bases and to earthbound farmers, who face challenges similar to those of space travelers, Rodriguez said recently.
"We're constantly under pressure here to do more with less, increase production, reduce costs," he said.
And on less acreage as more and more farmland is converted for development.
Rodriguez was a research scientist at NASA's Johnson Space Center in Houston before joining the UI faculty this fall. His lab studies complex systems, especially involving biological, chemical and physical components, by taking advantage of computing power to model them in detail as never before.
The UI researchers, in a NASA-funded program, are looking at such questions as what systems on a Mars flight would absolutely need to have a backup, and how long it would take to fix those that break down, for example to regrow a bacterial culture being used for waste treatment.
Reliability is a key factor. Three months out and halfway to Mars, travelers wouldn't have the option to abort to Earth.
In the computer models, the researchers can study how different parts integrate with each other and inject failures to see how the systems might recover, among other things.
Rodriguez said there are good reasons for wanting to grow stuff en route, or on a moon or Mars base in preparation for a trip, not the least that it's hard to conceive of hoisting enough material from Earth by rocket to supply a three-year journey.
Plants also can use up some waste, as fertilizer, and consume toxic carbon dioxide while producing life-giving oxygen.
Moreover, from a reliability perspective, crops and other biological components like bacteria used in waste processing have the advantage of being resilient. They can take some environmental instability and bounce back, Rodriguez said.
In addition, there could be psychological benefits from having plants, a link to home and a source of fresh food, along on the trip.
But crops require resources such as light, water, temperatures like those on Earth, day and night cycles – a lot of them in short supply, if not unavailable, in space. Some things you might grow, like corn or wheat, also require processing before they're eaten. All of that is subject to payload and power limitations.
NASA is looking more at pick-and-eat produce, in essence "a salad machine type system as opposed to a calorie crop type system," Rodriguez said.
He and other researchers for the space agency are examining ideas ranging from greenhouses employing hydroponics and supplemental lighting to completely enclosed growing chambers, "a box that can mimic Earth."