This week on the menu for astronauts aboard the International Space Station: a purplish-green sample of romaine lettuce, the first plant ever to be grown and eaten in space.
Of course, growing food in a low-gravity environment with little sun or water is a bit more complicated than planting gardens here on Earth. Astronauts must grow the plant in rooting “pillows” containing the seeds. They are grown in a unit with a flat panel that gives off red, blue and green lights using LEDs — which are responsible for the plants purple hue.
The lettuce that the astronauts will eat Monday is the second batch grown on the space station. The first was sent back down to the Kennedy Space Center in Florida in October of last year, where it was analyzed for safety. Scientists at Kennedy gave the produce a thumbs up, and a second batch of lettuce was activated in July.
“There is evidence that supports fresh foods, such as tomatoes, blueberries and red lettuce are a good source of antioxidants,” said Ray Wheeler, a researcher at Kennedy, in a statement. “Having fresh food like these available in space could have a positive impact on people’s moods and also could provide some protection against radiation in space.”
The astronauts will eat half of their lettuce crop, setting aside the rest to be packaged and frozen for analysis. They also have a batch of zinnias to grow, which will also be used to study how flowering plants can grow and pollinate with little gravity.
It’s not like astronauts on the space station never get any fresh food. The crew does get produce like apples and carrots whenever a supply ship is launched, but that’s limited and they must eat it quickly, according to a NASA payload specialist.
Being able to replenish food sources during much longer voyages would be essential for future space travelers, not only for nutritional needs but also to give astronauts something to do. It also gives crew members a living vestige to remind them of Earth.
“The farther and longer humans go away from Earth, the greater the need to be able to grow plants for food, atmosphere recycling and psychological benefits,” said Gioia Massa, also a scientist from Kennedy, in a statement. “I think that plant systems will become important components of any long-duration exploration scenario.”
NASA scientists also said that studying how plants grow with LED lights could help in growing food on Earth. The space station’s technology could be applied to urban plant factories or other scenarios in which plants are grown using electric light and where water needs to be tightly conserved.
In addition to taking breathtaking photos of Earth and the moon, the International Space Station has long been home to biology experiments. Crew members take advantage of their unique low-gravity and high-radiation environment to see how it affects living things like flatworms, mouse embryos and squids.
Whisky makers have also been interested in how microgravity can affect the aging process or change the taste of the alcohol. The Japanese distillery Suntory is also sending up samples of whisky to the station, following up on a sample of Ardbeg Scotch Whisky that sat up on the station for 1,000 days.