By D.A. Barber

The ability to grow food in extreme places will play an important role in future human space exploration. In fact, UA researchers are currently working on designs for a Martian food growth chamber. But for now, they are pleased to help improve the diets of scientists living and working at the South Pole.

The Controlled Environment Agriculture Center (CEAC), part of the University of Arizona College of Agriculture and Life Sciences, recently sent a “greenhouse” food production chamber to be incorporated in the new, almost completed Amundsen-Scott Research Station at the South Pole in Antarctica where temperatures can reach lows of minus 118 degrees Fahrenheit.

For seven to eight months of the year, the temperatures are so low that aircraft cannot land and no one can come or go. The UA growth chamber arrived just before the station closed for the winter.

“Station opening is in September, the start of the Austral Summer, and the dedication for the new research station and growth chamber was in November,” says Gene Giacomelli, UA professor of agricultural and biosystems engineering, and director of the Controlled Environment Agriculture program at the UA.

The ultimate goal of the food growth chamber is to provide a better quality of life for researchers by providing fresh salad crops and an environment where they can experience full spectrum lighting and plants that will help others understand how people can adapt to living in seclusion without seeing the sun for five and a half months.

“The main purpose for including the food growth chamber in the new station is also the psychological effect that it has on the station personnel,” says Giacomelli, who helped design and manage the project.

The CEAC is an interdisciplinary research, education and outreach facility located at the UA Campus Agricultural Center. Students and faculty from the College of Agriculture and Life Sciences, including agricultural and biosystems engineering; agricultural education; soil, water and environmental sciences; and plant sciences, currently participate in its programs.

But in the frozen wasteland where the sun doesn’t shine from March to July, scientists who endure the harsh winters have been craving a supply of fresh romaine lettuce, cucumbers, herbs, tomatoes, and sweet and hot peppers. Previously every few weeks during the Austral Summer, salad and fresh veggies were delivered to the station along with the air cargo, but those deliveries stop during the eight months of isolation during the southern hemisphere winter.

With that in mind, in February 2004 scientists got their wish with the delivery of the UA food growth chamber, which was constructed so the crew could easily manage it.

Funded by a $450,000 grant from Raytheon Polar Services Corporation via the National Science Foundation (NSF), the chamber is unique in several respects.

“This is the first time the NSF had designated that in the design of this new research station there would be a place to grow food. So when we bid for this contract we were given a floor plan and they said ‘this is how much space you have and what utilities are available,’” says Giacomelli.

The unit, measuring 18 feet by 28 feet, isn’t technically a “greenhouse,” as it uses no sunlight. Instead, artificial light is used to grow food in a fully enclosed and controlled environmental chamber to protect it from the harsh elements. And with no bugs, diseases or weather changes, keeping the nutritional levels and the water flowing in the hydroponic environment, it is a system where plants live solely in trays filled with water. Lettuce, herbs, tomatoes, cucumbers, and sweet and hot peppers are being grown in a re-circulating nutrient solution that is recycled over and over through the system of trays. The apparatus also provides the plants with carbon dioxide, which is shipped to the station as compressed gas and then pumped into the chamber.

Because of contamination concerns, the Antarctic Treaty states that soil, animal or plants are not allowed onto the southern ice, so the station staff are sent packed, sterile seeds. “From the day the seeds are started, it will take about 100 days to get the first tomato,” says Giacomelli. A head of lettuce would take about 30 days before it could be harvested.

The crop yields will be adjusted to the size of the current station population, which will include 200 people during the Antarctic’s three-month summer, and 30-40 people the remainder of the year.

“The lights, designed and manufactured by the Sadler Machine Company of Tempe, Ariz., are the most unique part of the whole design: high-pressure sodium lamps that are water-cooled,” says Giacomelli. Since high pressure sodium light bulbs radiate large amounts of heat during operation over time, each bulb is placed in a system of clear quartz glass water jackets, where water runs around the light fixtures collecting and removing this radiated heat from the lighting and acts as a cooling agent for the chamber. The cooler temperatures are practical to use in the confined space of a growth chamber where plants can get close to them and not be damaged by excessive heat. “The lamps were tested with support from NASA Advanced Life Support at Johnson Space Center, whose interest is in food production in space,” he says.

Automated controls for air temperature, light, humidity, watering and nutrients will enable researchers to know when things are doing well and when they are not.

“When the communication link has been completed between the new building and the rest of the world, we (the UA) will be able to see information on a daily basis of exactly what’s going on in there,” says Giacomelli, who notes that the parameters of the environmental controls could even be changed from campus if need be.

Besides raising leafy green and fruiting vegetables, the food growth chamber is equipped with a sitting room separated by a transparent wall so researchers can relax and enjoy the sight of lush green plants and more importantly ­ the artificial sunlight.

About two-thirds of the chamber is used for the crops, while the other one-third allows people to sit and absorb the artificial light for psychological benefits. That’s important since their health can suffer from seasonal affective disorder (SAD), brought on by a lack of full-spectrum natural light during six months of total darkness.

“The lights were not designed spectrally for people, they were designed for plants,” says Giacomelli. “But the intensity ­ the brightness of the lights ­ is what’s important.”

Part of the UA’s commitment to the National Science Foundation is to provide 18 months of educational training to the South Pole station occupants. A Webcam will allow Giacomelli and other faculty and students to aid the South Pole team when the plants are ailing. And starting next fall, Giacomelli hopes to integrate the Internet educational experience with his UA students.

The UA is no stranger to development of food production facilities within hostile environments. In the early 1970s controlled environment vegetable production greenhouses were successfully operated with university designs in the deserts of the Middle East and northern Mexico.

In Antarctica, UA researchers hope the lessons learned from their innovations in hydroponic food production and controlled environment agriculture will move the technologies that are changing the greenhouse industry around the world, and beyond. Including on Mars.

UA beat out Arizona State University and two NASA groups for the “Phoenix project” to Mars ­ dubbed NASA’s first Scout mission in its Mars Exploration Program. It will be launched in 2007 and land in May 2008. The Phoenix project is yet another UA-designed-and-built unmanned spacecraft capable of landing on Mars to conduct the tests on the Red Planet’s icy north pole crust to test for clues on the history of water, and search for environment suitable for microbes. Giacomelli is discussing with the Phoenix team the possibilities.

“We all know what’s going to follow the robots down the road,” says Giacomelli. “We want to demonstrate to the world that the UA can take the next step and start caring for people in space.”

One scenario is to send a mocked-up growth chamber to Mars after Phoenix lands and let the robots set it up growing crops as a demonstration of what could be available from a full-scale chamber when a manned mission lands.

“The most important thing is what it would be able to do is mine the carbon dioxide from the Martian atmosphere and the plants convert it to oxygen and begin storing it for people,” says Giacomelli.

Meanwhile, between the South Pole growth chamber project and testing the possibility of the Phoenix robot accomplishing such a chamber assembly plan, Giacomelli hopes to have a viable demonstration project for Mars missions down the road.

Design and construction of the chamber was a cooperative effort with the CEAC and its small business subcontractor, Phil Sadler of Sadler Machine Company, which was responsible for the mechanical fabrication of the growing systems and lights. Undergraduate and graduate students assisted in the drafting, engineering, and labor components of the effort, gaining valuable, real-world experience. And UA farm and support personnel assisted in making this chamber a successful endeavor.

Lane Patterson, a recent graduate in Agricultural and Biosystems Engineering, who was highly involved with the chamber design and testing, was hired by Raytheon and will arrive at the South Pole facility in February to support operations.