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UA greenhouse out of this world

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UA greenhouse out of this world

July 12, 2012

There are many reasons for gardening's renewed popularity: an aging population with more time to spend gardening, increased cost of buying food in grocery stores, the proven negative effects pesticides and chemicals have on our bodies, understanding of the important role plants play in providing our planet with clean air and water, and knowledge of the simple joys gardening provides which offer calmness to our increasingly complex lives. “Back to nature” is no longer a fad but a way of life.

Even astronauts may someday be gardening. The University of Arizona's scientific research staff, headed by Gene Giacomelli, director of Controlled Environmental Agriculture, has designed a lunar greenhouse that may travel on missions to the moon and elsewhere.

Plants grown in the greenhouse will absorb carbon dioxide and replenish oxygen used by the astronauts. They will also provide clean drinking water by recycling distilled urine through the plants' systems to produce clean water vapor which can be drunk. Vegetables raised in the greenhouse will provide at least 50 percent of the nutritional requirements of the astronauts, with the possibility of fish/shrimp aquaponics providing the other 50 percent. The 3Rs — reduce, reuse, recycle — work just as well in space as on Earth.

Funding for the current phase of the UA lunar greenhouse project comes from a NASA grant that will also allow experimentation with other types of controlled environments. Since 1999, when then-governor Jane Hull recommended funding of the Controlled Environment Agriculture program at the UA, the university has been a leader in the research of controlled environments such as greenhouses for specialized crop production.

Because of the moon's harsh conditions, the lunar greenhouse will be buried beneath the surface. Water-cooled lamps or sunlight piped in using fiber optic cables will give the plants necessary sunlight for photosynthesis. The goal is to show that vegetables can be grown in space and can be incorporated into the diet of astronauts working on long-term missions. A diversity of crops grown in the lunar greenhouse will provide a diversified diet for the astronauts.

“The moon has one-tenth the gravitational pull of Earth, but that is enough to allow plants to grow successfully in the greenhouse. Even asteroids have some gravity and can serve as greenhouse locations,” Giacomelli said.

When asked where the idea for a lunar greenhouse originated, he said, “A small businessman in Tempe, Phil Sadler, owner of Sadler Machine Company, came up with the idea and built a prototype in his machine shop. Working with the University of Arizona for over 14 years, his concept has evolved into the UA Lunar Greenhouse Outreach and Teaching Module, which was on display mid-June through July 4 at the San Diego County Fair.

“Our hope is to present this exhibit to as many people as possible over the next few years. Since the fair's theme this year was ‘Out of This World,' our Lunar Greenhouse Outreach and Teaching Module fit right in. Last year, over 1.5 million people visited the fair; and this year, I expect even more people attended. The venue was a great opportunity to educate the public concerning fundamentals of hydroponic gardening, the importance of recycling Earth's resources, especially its nutrients and water, and helping people realize there is not an endless supply of resources on Earth. We must use what we have wisely,” Giacomelli explained.

Alex Kallas, founder of Ag Pals, a nonprofit organization in San Diego, was the spokesman for the lunar greenhouse at the fair. Ag Pals presents educational programs to schools and organizations concerning agriculture and its importance to our environment.

“I was excited to be able to help the University of Arizona present this remarkable project. The concept has now moved from academia to the general public. That is exciting. At the fair, we met people who drove in from Arizona and northern California just to take a look at the greenhouse and learn more about it. It is always exciting when we can answer questions and help people gain a better understanding about the lunar greenhouse and how important recycling is on Earth and in space,” Kallas said.

“Knowledge gained from this project will have many benefits here on Earth,” Giacomelli added. “We are finding that there is great potential for this type of greenhouse to be added to a family's home to help provide clean air and fresh food. This could relieve some of the pressure on farmers to provide food for Earth's growing population. Gardening in greenhouses with controlled watering can help improve the sustainability of life on Earth. Controlled environments can also be a good location to grow plants used in the pharmaceutical industry. Gardening can become a part of a person's life and can give back so much.”

From the outside, the lunar greenhouse reminded me of a slinky. Its tubular shape was covered with a special plastic and a thermal blanket. The sealed aluminum door on one end of the greenhouse was opened, and I peeked inside. I saw rows of green vegetables growing hydroponically using a system of cables strung the length of the greenhouse from which sealed membrane envelopes filled with nutrient-rich water were hung. A variety of vegetables were growing in the envelopes. The water supply to the envelopes came from a 100-gallon tank, with a series of drip lines slowly adding nutrient-rich water to the plants on a continual basis. As crops are harvested, new ones are started.

Giacomelli said, “Another positive benefit of the lunar greenhouse for lunar missions would be the reduction of food, water, etc., carried on board the space vehicle to feed the astronauts. Instead of carrying thousands of pounds of food supplies, packets of seeds, as much fertilizer as the weight of each astronaut, water to start the greenhouse, and a lightweight greenhouse system would be carried. The greenhouse can be folded down to 1 meter. When open, it expands to 5.5 meters in length and 2.1 meters in height.”

After a long day of moonwalks, astronauts could spend time harvesting in the greenhouse as a way to relax and enjoy a bit of nature from back home. However, the gardening system is all computerized and controlled from Earth, so is self-maintaining.

In the future, using the controlled environment of greenhouses for farming here on Earth could be one means of protecting the Earth's water resources. Drip line irrigation could save significant amounts of water which are normally lost using traditional irrigation. Traditional irrigation methods work best for certain crops, but farmers in the future will be taking many lessons learned from outer space gardening and applying them to their operations in order to best utilize our limited water and land resources. The UA lunar greenhouse definitely proves that gardening really can be “out of this world.”

Karen Bowen is a master gardener and member of Yuma Garden Club. This column is sponsored by the Federated Garden Clubs of Yuma. For more information, go to