2005 Year in Review

Farming in Space?

Source: Luis Rodriguez, 217-/333-2694

How do you produce food on Mars? And what happens to all of the waste that builds up during a three-year trip?

These are just some of many life-support issues that a University of Illinois researcher is grappling with as he helps NASA prepare for extended trips to Mars.

"NASA's new goal is to go to Mars," said Luis Rodriguez, professor of agricultural and biological engineering. "But the technology they're working on is about a decade away from preliminary testing, hopefully on the surface of the Moon."

Rodriguez came to the U of I from the Johnson Space Center in Houston, where he recently won a NASA grant, a Research Announcement, for his work on new life-support systems. He said these systems are new because there is a major difference between the anticipated mission to Mars and missions made by the space shuttle today.

"Right now, space travel is like a camping trip," he said. "Astronauts take all of their supplies with them--their oxygen, their water, their food. If something's needed at the space station, the space shuttle or the Soyuz from the Russian space agency can fly up on a regular basis and bring them supplies."

However, regular re-supply trips to Mars aren't possible, said Rodriguez.

"A one-way trip to Mars takes six months," he said, "and the planets align so that you can only do this six-month, one-way trip every two-and-a-half years. A round trip to Mars takes three years. And it's not currently possible to 'pack' three years of food."

So NASA is focusing much of its effort on developing systems and technologies that will allow astronauts to produce their own food, among other things. Crop production and processing is particularly challenging, said Rodriguez, because crops require a long list of resources, including light, water, fertilizer, carbon dioxide, Earthlike temperatures, day and night cycles, and crew time.

"Light is the only resource that exists on Mars in any useful form, and even that would have to be supplemented, since Mars is much further from the sun and light intensity is lower," said Rodriguez. "Everything else must be provided from Earth."

A Mars greenhouse, using hydroponics and fertilizers brought from home, and providing supplemental lighting and sufficient atmospheric pressure, is one system being considered for crop production. Another is a series of completely enclosed, well-insulated growth chambers that can more easily moderate temperatures and mimic a suitable environment for a crop, though at a much higher energy cost.

Post-harvest processing is also a consideration. Although some vegetable crops are essentially pick-and-eat, other crops, (such as grain, oil and protein) require multiple steps before edible foods are produced.

"Even though crop production and processing is labor intensive," said Rodriguez, "it should provide a strong psychological benefit to the crew, serving as a tangible green reminder of home during a long voyage."

Recycling resources is another issue NASA must address.

"All wastewater will need to be cleaned back to potable drinking water standards," said Rodriguez. "Oxygen and the atmosphere need to be maintained, so the carbon dioxide that is exhaled needs to be recycled back into breathable oxygen--and on down the line."

The challenge, said Rodriguez, is to figure out ways to do all these things reliably.

"That's the key here. When you're halfway to Mars, when you're three months out, the Earth is nothing but a star and Mars is nothing but a star. There is no abort-to-Earth option," he noted.

"So we're looking for new ways to design these different systems so that we can get there and come back with a fair amount of reliability--or at least acceptable risk. We want to develop the right technologies and design the proper systems, and then be able to measure those systems in such a way that we can put a number on what reliability is."

Rodriguez concluded, "It's hard to get bored working with NASA."

by  Editor, theCity1.com
December 11, 2005