Summer internship with NASA proves rewarding for Elon native
Taken at face value, the typical commencement speech would seem to suggest that the purpose of college is either to “shoot for the stars” or else “plant the seeds” for a future profession.
Only the most fumbling of speakers would even think to combine these mixed metaphors into a single oration. Yet, this collision of rhetoric has found a natural nexus in one undergraduate from Alamance County who has spent this summer, literally, sowing the ground for a career in the space program.
A student in Biological and Agricultural Engineering at N.C. State, Sawyer Exum is currently an intern at NASA’s Kennedy Space Center, where he has devoted his time to research on the production of space crops.
For many people, the mere mention of “space crops” may conjure up memories of Matt Damon’s character in The Martian. For those who are a bit fuzzy on this decade-old blockbuster, Damon plays a member of an ill-fated expedition to Mars who’s accidentally marooned on the surface of the Red Planet. He nevertheless survives the ordeal thanks, in part, to his ingenious use of human waste to grow his own potatoes.
It wasn’t long after this movie’s release that the references to “poop potatoes” had become a staple of late-night comedians. But to Exum, this now-dated punchline is overshadowed by the scientific achievement of producing food in such an otherworldly setting.
“Growing crops in space is the hardest ver sion of agriculture there is,” Exum acknowledged from Cape Canaveral earlier this summer. “[There is] high CO2, low pressure, no soil, no sun. Even the water has to come from somewhere, whether you’re on the space station or a Moon base.”
As grueling as gardening may be beyond the balmy bubble of Earth, the cultivation of space crops has been an ongoing preoccupation for the U.S. space program. Over the years, NASA has experimented with food crops in low-gravity environments like the International Space Station. It has also established greenhouses in the American desert to mimic the marginal conditions on the surface of Mars.
So, it wasn’t much of a departure for the space agency when it received an internship application from Exum that expressed an abiding interest in the production of space crops.
By the time he left for Cape Canaveral in June, the rising senior had learned that he’d been assigned to work on a project that attempts to grow hydroponic lettuce using the chemical ammonium as fertilizer.
A compound related to ammonia, ammonium is a rich source of the nitrogen that plants need to survive. It is also slightly acidic, although it has other properties that give it an edge over nitrate-based fertilizers for use in low orbit.
According to Exum, the goal of the hydroponic lettuce project is to find ways to improve the plant’s tolerance to ammonium. He added that, when he first heard he’d been assigned to this venture, he didn’t know just how deeply involved he’d be in the work.
“I thought I’d be assisting. Instead, I’m contributing,” he conceded, “and my mentor has been phenomenal. He’s taught me how research actually gets done at NASA, which is not something you learn in a classroom.”
Alongside his contributions to the research at NASA, Exum’s internship has allowed him to become familiar with spectrophotometry, LED lighting systems, 3-D printing, and other cutting-edge technology. It has also introduced him to some of the space program’s biggest celebrities, including SpaceX’s Crew-11 and the crew members of Artemis II.
More importantly, the past couple of months have solidified Exum’s sense of where his own future is heading.
[Story continues below photos of Exum in N.C. State lab.]
“This experience has clarified that I want to pursue research and a career in controlled environment agriculture and waste recycling,” he explained. “Further out, I want to apply to the astronaut corps one day.”
As exotic as this vision may seem to some people, it makes perfect sense to Sawyer Exum’s dad, Steve.
A professional photographer who also serves on Elon’s town council, Steve Exum acknowledges that Sawyer’s internship with NASA has proven an ideal fit for his son’s idiosyncratic interests.
“He was always interested in agriculture,” the elder Exum elaborated in a recent interview. “I also think that the challenge of trying to grow something in a very harsh environment appeals to him…I think he has the idea that he’d have a piece of land and just live off the grid.”
If all this sounds a little like Mark Watney – the name of Matt Damon’s alter ego in The Martian – it isn’t exactly dispelled by Sawyer Exum’s own thoughts on the film.
In fact, Exum turns a scientist’s eye on the “poop potato” phenomenon that so many others have been content to pump for its scatological humor.
“Potatoes were a great call,” he goes on to elaborate. “They have a huge calorie yield, and you grow them from spare potatoes instead of seeds.
“Mars dirt isn’t soil; it’s crushed rocks with a side of toxic salt,” Exum continues. “Watney’s plan was to fix that with the crew’s freeze-dried poop…but he skipped the good stuff. Almost all the nitrogen a person produces leaves in urine. So, he had a fertilizer supply on tap the whole time and went with an option that’s mostly germs.”
