by Linda Herridge
NASA Kennedy Space Center
Red romaine lettuce and other fresh vegetables could be on the menu for astronauts in the future. NASA astronaut and Expedition 40 Commander Steve Swanson harvested the first fresh vegetable crop, Veg-01, on June 10 from the Veggie plant growth system on the International Space Station (ISS).
“I was all smiles watching Swanson harvest his space lettuce, and I noted a great deal of excitement among the other crew members,” said Trent Smith, a project manager in the ISS Ground Processing and Research Project Office at Kennedy Space Center.
The following day, researchers harvested a control version of Veg-01 inside the Payload Development Laboratory at Kennedy’s Space Station Processing Facility (SSPF). The ‘Outredgeous’ red romaine lettuce was grown on the space station and in the control laboratory for 33 days.
The ground team was able to monitor Veggie on the space station through a downlink in the SSPF. Veggie experiment procedures on the space station — including activation of the plant pillows containing the red romaine lettuce seeds, delivering water and monitoring plant growth — were precisely mirrored on Earth in the control lab.
One of the goals of Veg-01 was a hardware test of the growth system, according to Gioia Massa, NASA project scientist for Veggie, also in the ISS Ground Processing and Research Project Office. Another goal was to get some baseline data for food safety of the plants.
“We want to know if there is anything on the station that might grow in the plant environment that could be harmful for the crew,” Massa said. “We’ll be doing microbial analysis of the plants, some of the plant pillows and the bellows from the Veggie growth system.”
On the space station and in the control lab at Kennedy, the tops of the lettuce were cut away from the plant pillows and swabbed for microbial samples. The pillows and bellows also were swabbed. The plants, sample swabs and a couple of the plant pillows were packaged and placed in a minus 80-degree freezer for storage.
“Our samples will be frozen until the flight samples return on the SpaceX’s fourth commercial resupply mission,” Massa said. “Then we’ll be able to do analysis on both of them.”
Researchers will measure the antioxidant, anthocyanin and mineral levels in the lettuce. According to Massa, red romaine lettuce tends to have higher levels of antioxidants than other leafy greens; higher antioxidants help counteract the effects of radiation in space. The data will be shared with NASA flight surgeons, the astronaut crew office and microbiologists at Johnson Space Center in Houston, with the hope of approval for the crew to grow and eat a red romaine lettuce crop in orbit.
“Our end goal is for food production, and Veggie is our first step for NASA to be able to achieve food production systems for space,” Massa said. “We’re looking at developing what we call a pick-and-eat capability for space station within the next few years.”
Besides having the ability to grow and eat fresh food in space, there also may be a psychological benefit. The crew does get some fresh fruits or vegetables, such as carrots or apples, when a supply ship arrives at the space station. But the quantity is limited and must be consumed quickly.
“We think that having that additional component of fresh food grown on the station would make the crew generally happier, and hopefully healthier,” Massa said. “It’s something to look at. It’s something that changes with the passage of time.”
Massa said a dedicated team at Kennedy, including engineers, scientists and project managers, worked on Veggie for several years. Engineers and scientists at Orbital Technologies Corp. (ORBITEC) in Madison, Wisconsin, built the Veggie hardware and worked with NASA to prepare it for flight.
“Veggie has lit a spark in everyone that’s been involved with it,” Massa said. “It’s been exciting for the crew. It’s been exciting for the team in the Payload Operations Center.”
What’s on the horizon for Veggie? The plant growth system now is available for other scientists to propose experiments, and a number of them are being reviewed for the future.
“We do have a list of other crops that we think could grow well in Veggie. Different crops could be grown in different sizes of plant pillows,” Massa said. “We’re even doing some research on dwarf plum trees to see if those might be able to grow in Veggie.”
An experiment going up to the space station on SpaceX’s fifth commercial resupply mission will use Veggie as a platform to grow Arabidopsis, a small flowering plant related to mustard or cabbage. Arabidopsis is of particular interest to plant biologists because its entire genome sequence has been modeled, and changes to one of those model organisms are easily observed.
One experiment is from the University of Florida in Gainesville, and the other from the Nobel Foundation in Oklahoma. Both will grow Arabidopsis in petri dishes using Veggie’s LED lights, not pillows.
According to Massa, these dishes will be harvested in orbit and fixed or preserved to allow investigators to look at different gene expressions related to developmental cellular biology.