To survive a round-trip journey through the Earth’s atmosphere and into outer space, astronauts must have with them a few things: gear, food, water and clean air.
About four years ago, Amy Grunden, an assistant professor in microbiology, started a project to help them get at least the last two items on that list.
She started her project, which she described as “a little complicated,” in collaboration with Wendy Boss, a plant biology professor, and a team of students who were or are enrolled in extreme biology courses.
Its main goal was to develop a plant that could live through harsh conditions natural to space travel but that could also provide astronauts with clean air and water.
“Wendy and I thought about the fact that NASA has these target man missions where they go to the moon and Mars for an extended period of time,” Grunden said. “But NASA doesn’t really have bioregenerative resource systems.”
These systems, she said, provide clean air and water by scrubbing out carbon dioxide and replacing it with oxygen. That sort of life support system is most likely going to be plant based.
“The big problem, though, is that there’s lots of different environmental extremes that these plants would be exposed to on space missions,” Grunden said. These problems include elements like radiation, low pressure, high levels of carbon dioxide and fluctuating temperatures. “There’s no good plant system available.”
To face these elements head on, and without dying, plants need to be nearly indestructible.
“Basically, we’re trying to design plants that are going to be a lot hardier. Ones that have less of a chance of failing in space,” she said. “If you send man missions they’ve got to have a source of food and life support system. If it’s going to be plant-based, it’s got to be really robust.”
So Grunden and Boss turned to extremeophiles — plants that can survive, and even thrive, in extreme environmental conditions.
The team received funding from the NASA Institute for Advanced Concepts, which funds “really high-risk, out-there, forward-thinking projects,” Grunden said. “They claim they fund revolutionary research that couldn’t get funded otherwise.”
With that new capital, they looked to create an extremeophile from a regular tomato plant.
“We took special genes that we knew were responsible for allowing these organisms to thrive and introduced them to plant genomes,” she said. “The plants then are given a kind of protection against these extremes.”
The genomes they first used were Arabisopsis, which is a small, flowering weed that can be used as a model plant — a plant that “everybody studies when they want to figure out an aspect of physiology of the plant.”
Arabisopsis is already a plant that is hard to kill, but when Grunden and her collaborators injected genes from extremeophiles into the weed, they found that it could tolerate heat, high light and drought stresses.
With those results, they sent a proposal to the USDA, asking it to fund a project that would perform the same experiment on the tomato, a plant that is more appropriate for a bioregenerative life support system.
About five weeks ago, Grunden and Boss received a letter from the USDA stating the funding had been approved.
The gene added to the tomatoes, Grunden said, is an antioxidant that helps the plant deal with environmental stresses.
Stress a plant incurs causes it to release reactive oxygen species, which can shorten the plant’s life span. Antioxidants injected into a plant detoxify those reactive species, Grunden said, making the plant more stable and, in turn, more beneficial to astronauts.
And the potential application isn’t just in outer space. Grunden said such an experiment can be used on Earth, too, to make plants drought resistant so they can better deal with temperature changes.
“That’s why the USDA funded us,” Grunden said. “Agriculture may need to have something like this to improve the way crops deal with environmental stresses, which is an international cause. That seems to be how a lot of research that’s being done for space ends up being used here on Earth.”
Modifications like this can allow plant biologists and farmers to improve the way they grow plants, she said. Such a process can provide “greater density and greater yield, which means you can feed more people.”
Isaac Owolabi, a senior in aerospace engineering who worked at NASA’s Langley Research Center in the summer of 2007, said the application of space technology on Earth can not only provide cheaper and more accessible technology to the general public, but also can bring a divided nation together.
He mentioned the first time man landed on the moon in 1969, noting that it was an event that united a nation divided by racial issues and the ongoing Vietnam War.
“That was one of our proudest moments in our nation,” Owolabi said. “It’s something everybody could say, ‘I had something to do with that.'”
According to NASA’s 2008 fiscal year budget, they will spend more than $17 billion. Although this is more than the budget in previous years, Grunden said the United States is starting to lag behind other countries in space exploration.
“If we don’t continue doing good research, we’re going to be left behind,” she said.
