On Nov. 11, 2020, NASA astronaut Kate Rubins photographs the first major milestone of the Plant Habitat-02 (PH-02) experiment aboard the International Space Station. The investigation studies the growth of radishes in a microgravity environment. NASA chose the radish because it’s a model plant: both nutritious and edible, having a short cultivation time, and being genetically similar to Arabidopsis, a plant frequently studied in microgravity.
Growing inside its Advanced Plant Habitat for 27 days, the plants require little maintenance from the crew. The growth chamber contains LED lights, a porous clay material, and a controlled system for releasing fertilizer to deliver water, nutrients, and oxygen to the plant’s roots. Cameras and more than 180 sensors in the chamber allow researchers at NASA’s Kennedy Space Center in Florida to monitor plant growth as well as regulate conditions such as water distribution, moisture levels, and temperature.
The crew aboard the orbiting laboratory is slated to harvest the radishes later this month. Samples will then be returned to Earth for researchers to better examine how well the radishes grew.
With plans to explore the Moon and someday Mars, NASA is gaining a better understanding of how to grow fresh produce in space for crew on long-duration missions farther from home. As part of the Artemis program, NASA plans to establish sustainable exploration on and around the Moon by the end of the decade, and will be able to send crew supplies from Earth. Future astronauts bound for Mars will travel for about two years before returning to Earth and will have to carry all the supplies they need for the duration of the mission. Learning how to grow food closer to home aboard the space station will help determine which plants thrive the best in microgravity and offer the best variety and nutritional balance for a Martian menu.
Photo credit: NASA/Kate Rubins