From its beginning, mankind has looked up to the stars and wondered what secrets the vast expanse held. Despite the best efforts of scientists through the ages and the advancing leaps and bounds of technology over the last several decades, space holds her cards close to her chest.
But a couple of projects and breakthroughs from Utah—a tiny speck on a little blue planet in a big, big universe—could help shed some light on some of those mysteries.
Green Thumbs in Space
For all the stories of brave space explorers, manned spaceflights are fraught with complication, from the effects of zero gravity on the body to the challenge of having and storing enough supplies to keep both spaceship and pilot on track. For long flights or colonization, producing food is a mandatory challenge to address. Over the last three decades, Dr. Bruce Bugby, a professor of agriculture at Utah State University, has been trying to find a solution.
Bugby has spearheaded multifaceted studies on growing plants in space, a project recently popularized by the news in August that astronauts had just had their first “space salad,” and later in the year by Matt Damon’s depiction of growing plants on Mars in The Martian. Helping plants survive and thrive in space comes with its own challenges, he says, but a lack or change in gravity is not one of them.
“The lack of gravity is not a critical issue for plant growth. It might be for people—all people have lost calcium from their bones; we’re still working on what to do with people in microgravity, but the plants seem to do just fine,” he says.
That immunity to gravitational challenges comes with a caveat: watering the plants. On Earth, when a plant is watered, the excess moisture drains out the bottom. Not so in space, where any extra water just sort of floats in the soil around the roots.
“We’ve killed a lot of plants in space by overwatering them,” Bugby says.
Because water won’t even drain as far as from the top of the soil to the roots, a prescribed amount of water is delivered directly to the root area through a syringe. The plants’ water needs are measured by moisture sensors in the soil.
Plant growth is controlled by the strength of the lights overhead and the length of time they shine on the plants. This, too, is more difficult in space—not because of any factors that make turning on a bulb more difficult, per se, but because when plants grow, they need carbon dioxide. In that respect, they also function as a sort of natural air filter, Bugby says, but it needs careful calculation to make sure the rate of plant use of carbon dioxide matches that rate of exhalation by astronauts, and that the rate of astronaut use of oxygen matches what plants are giving off.
Bugby started his research on plants in space in 1981, part of a four-university effort to study the possibility and mechanics of growing crops in space and in colonies. NASA lacked sufficient equipment for its own experiments, so Bugby, a plant physiologist, and his co-researchers built and installed elaborate growth chambers to study plants’ reactions to their environments.
“It was an exciting time. The space program was going big then, and went that way for more than 20 years,” he says.
Several years ago, as NASA was facing serious budget cuts, the steady stream of funding for the project all but dried up to a trickle. While the project is not what it was, the work continues, Bugby says, both on campus and in space.
The trick about space, or colonizing another planet somewhere, is making sure all of the resources are available—and stay available. And finding out how to make that work, even in the barest of situations, takes a lot of trial and error.
“We don’t think about stuff now—something breaks in your house and you run to Home Depot and get a part and fix it because we’ve done it so many times. But if you backpedal to coming to Utah in handcarts, there wasn’t Home Depot—people had to make it work or figure it out. That’s the way it is in space,” Bugby says. “It’s the nature of doing something new for the first time anywhere. That’s what research is. People think research is so expensive. That’s because we don’t know what we’re doing. We’re trying new things. We do our best to predict what’s going to happen and then we have to test it. Sometimes we get it right, and sometimes we have to try other things.”
Besides air being recycled between people and plants like a gaseous tennis match, water has to be filtered for ever-recycled use. The number and kinds of plants, too, are limited based on space for growth and the water available. For this reason, Bugby says, a lot of the research has gone into figuring out which plants give the most bang for the proverbial buck.
Any diet for long-term space travel would have to be vegan, he says, as any kind of livestock is out of the question—the extra land to grow enough food to feed them negates any benefits they bring to the table. In addition to being animal product free, the diet couldn’t include fruit trees, which take up too much space. Other foods, like tomatoes and strawberries, need to be weighed for the psychological benefits they’d bring with their variety with their relatively low yields. With dense, nutritious crops and careful recycling and controlled but continuous growth rates, a family of four could survive on less than a quarter acre of growing space, he says.
“It’s even more limited than a traditional vegan diet. Then we start to ask—what will we grow?” Bugby says. “We’ll grow potatoes. We’ll grow wheat, we’ll grow rice—these are staple products that have fed people for centuries.”
The Osiris Rex Mission
While Bugby’s research has been centered around how to help feed the future, Utah State University’s Space Dynamic Laboratory has entered into a cooperative venture focused on better understanding the distant past, with hopes the information gleaned there will help with upcoming projects.
The SDL designed and developed the three focal plane arrays—sensitive, high-tech cameras for research and navigation—for Osiris Rex, a University of Arizona-led project launching next September. Osiris Rex will travel to Bennu, a well-known and well-studied asteroid in orbit around the sun, and take close-up pictures of the face of the asteroid, as well as touch down to take samples of the soil on its surface, says Dr. Jed Hancock, director of the civil space division of SDL. It will return to Earth in 2023, landing in Tooele County’s West Desert.
The focal arrays developed by SDL will help Osiris Rex find the asteroid and then map the surface and document the landing site. They took three years to develop, in no small part because of the heavy demands placed upon equipment for space missions.
“You have to understand that the electronics have to survive space for seven years. They’re out in an environment where there’s radiation and they have to survive temperature extremes. You also have to build and design so it can survive launch from a rocket. When a rocket takes off, there’s a lot of shaking that goes on. These electronics have to be designed and tested thoroughly to make sure they’ll survive in space,” he says. “You have to do all these things using as little power as possible. In space, power is a limited resource.”
Bennu is one of about six asteroids with carbon on their surface that are within a relatively close range. Although it has been extensively studied from a distance, little is known about its geography, Hancock says, and because it contains carbon, it could give clues about the beginning of life.
“By studying the soil from this asteroid, scientists can better understand the formation of our solar system and potentially have a time history, a time capsule of the origins of life, where this asteroid contains carbon,” he says. “When we observe asteroids from the Earth, we can see them but we can’t see them in detail. [The Osiris Rex mission] gives us a close-up perspective of what an asteroid is really like. It’s like observing New York City from a magazine. It’s a lot different to stand on the streets.