Have you ever wondered what astronauts eat in space?
According to the NASA website, they are able to choose from a wide range of food items, including “fruits, nuts, peanut butter, chicken, beef, seafood, candy, brownies, etc.”, provided in non-perishable forms.
And soon, astronauts will be able to enjoy nutrient-rich, space-grown lettuce as part of their meals.
How Is The Lettuce Grown?
From 2014 to 2016, astronauts at the International Space Station (ISS) successfully grew three batches of lettuce. The lettuce was grown in a vegetable production system called “Veggie.”
Three important units make up the system:
- plant pillows, which are sealed packages for plants to grow in, with ceramic clay in them instead of soil. The ceramic clay stays together in zero-gravity, and stores air and water better than soil;
- LED lighting, used to replace sunlight;
- a watering system, which involves astronauts injecting water into the plant pillows.
The lettuce grew undisturbed for 33 to 56 days. When finally it was harvested, astronauts wiped the vegetable with sanitary wipes (washing products in zero-gravity is impossible) and ate it, or sent samples back to Earth for analysis.
Scientists confirmed that “space lettuce” contains as many nutrients as lettuce grown here on Earth. In fact, the experiment revealed that the space lettuce is richer than regular lettuce in a certain compound called phenolics. Phenolics are good antioxidants, which keep the body safe from diseases.
The lettuce has more bacteria, because of the small, humid package it lived in, although there were no signs of dangerous bacteria in the batches grown in the ISS.
Why Is This Exciting?
The experiment’s success is significant for future space pioneers: now we know that produce can be grown in space for long-term missions, such as a future trip to Mars.
In the pre-packaged foods currently available to astronauts, nutrients and flavor perish after they’ve been stored for a while. Eating bland, nutrient-poor food for long periods could have an impact on astronauts’ physical and psychological well-being, potentially triggering health problems such as weight loss and depression.
But growing vegetables and fruit would lead to a healthier, richer diet, and astronauts would also benefit from caring for the plants. Plants are crucial for generating oxygen and removing carbon dioxide. In a closed system like the ISS, plants are important in keeping the air fresh.
There are still some things that need figuring out though. To have a healthy diet, astronauts will need to produce a variety of vegetables and fruits. But how will they recycle the inedible parts of the plants? And how will they wash the products in a cleaner and more efficient way?
Scientists continue to ponder these questions, but in the meantime, NASA plans to keep experimenting with other plants, such as wasabi mustard, Chinese cabbage, bok choi, and kale.
Sources: NASA, Guardian, NYTimes, Engadget