Astronauts hoping to eat salads during their interplanetary travels got some good news this week. NASA scientists have been examining the red romaine lettuce grown on the International Space Station (ISS) and just determined that it’s not only safe to eat — it’s also just as nutritious as lettuce grown on Earth (h/t New York Times).
The lettuce was grown from 2014 to 2016 in Veggie, a hydroponic growth chamber onboard the ISS. NASA scientists have been examining samples culled from Veggie and comparing them to romaine grown here on Earth under similar agricultural conditions (same humidity, temperature, etc). Today they released a paper which states that the two lettuces had similar nutritional values, though the space-grown lettuce had higher levels of (unharmful) microbes, likely due to their proximity to the astronauts.
Of course, astronauts cannot survive on lettuce alone; nor will they be able to rely on packaged food for multi-year journeys (the trip to Mars will take at least seven months, one way). Since 2016 Veggie has also grown other plants including mizuna and cabbage. NASA scientists are working to launch the Española chile pepper into space, which would make it the first fruiting plant grown and harvested on the ISS. And over at the University of California, Riverside they’re hard at work developing tomatoes with smaller stems and leaves that would be better suited to space travel.
Interplanetary dining exploration goes far beyond fruits and vegetables. In December astronauts baked sugar cookies on the ISS with Zero G Kitchen’s special oven. SpaceX is flying coffee and hemp cultures into space this year to see how zero gravity will impact the plants’ growth. On the protein front, Aleph Farms has successfully grown animal muscle tissue cells on the ISS. Japan is also experimenting with new ways to feed astronauts through its 30+ company initiative, Space Food X.
According to the NASA study, this Romaine experiment indicated that “leafy green vegetable crops can produce safe, edible, fresh food to supplement to the astronauts’ diet.” Good to know that space travelers will have a salad to balance out their space cookies and wine.