How might Earth’s plants survive on another planet?

Canadian students are going to be among those looking for the answer through a project growing plants on the International Space Station.

The mission “ExoLab-9,” from the California-based organization magnitude.io, is set to launch on a SpaceX resupply ship on August 29, allowing students from ages kindergarten to Grade 12 to learn about how plants grow in space.

Dianea Phillips is a science education consultant based in Montreal; she is principal investigator for Canada with magnitude.io and ExoLab, and a frequent collaborator with The Royal Astronomical Society of Canada’s Montreal Centre. She said Canada has been involved with ExoLab since 2019, and the ExoLab-7 and ExoLab-8 projects that saw Canadian students participate were valuable collaborations for those isolated at home during the pandemic.

“The primary question involves, how will we be able to feed future explorers on long term missions?” she said. “Earth is the mothership, but we need to consider that Earth may not be our only home in the future. At the same time, we must turn our eyes to food sustainability here on Earth as well.”

Similar in concept to “CubeSats” — small satellites that perform Earth observations or other experiments in space — the ExoLab program will launch the plants to the space station inside of a 10-centimetre cube. Unlike a CubeSat orbiting in space, however, the ExoLab cube will be perched inside the space station at the United States National Laboratory section, where autonomous experiments run without too much need for busy astronauts to check in.

Lighting sensors, carbon dioxide readings and images will all be used to monitor the plant growth, with the information sent down through an internet connection. Students at schools around the world can check in — including those Canada, Germany, South Africa and Sri Lanka, to name a few. 

ExoLab-9 is the ninth mission from magnitude.io, which started in 2013 to engage students in science, technology and engineering. While early attempts at programming CubeSats didn’t work out, plant-based ExoLab experiments using the same CubeSat size have been working well on the ISS since the first such launch in February 2017. The initial mission studied Arabidopsis thaliana — a plant used often in space exploration missions, allowing for students to compare their data to past missions.

Phillips said the students are asked to “stretch their imagination,” thinking about what humans need to know to live or thrive on another planet and how to plant a garden in the bare regolith of Mars.

“We consider the questions: How might we take red clover (trifolium pretense), fix the nitrogen and create nodules that will store nitrates — then convert what a plant can use to grow?” Phillips said about ExoLab-9.

Just like astronauts, plants face their own challenges when leaving Earth. Increased radiation may alter growth patterns. Microgravity changes the ways in which roots pick up water. The enclosed environment of the space station may make it difficult to grow in the same way as in the free air of a field on Earth. 

Learning about such plant behavior will be crucial as Canada joins other nations in the NASA-led Artemis Accords, which aims to put people on the Moon later in the decade. Far away from the resupply ships that space station astronauts depend upon, NASA anticipates plant growth will be crucial for the settlement’s food and the astronauts’ well-being, among other factors. 

If all goes to plan on the lunar surface, any “lessons learned” could be brought to an eventual human Mars settlement, Phillips said.

Phillips said students need to bring cross-disciplinary skills to the table – like research, observation, digital literacy and critical thinking skills – to add to science and social science disciplines such as astronomy, history and engineering. Arts also is crucial, she noted. Working together in teams adds the critical skills of time management, leadership and problem solving, among other things, that they will need in post-secondary education and the workplace.

Phillips said the program is always looking for more students and teachers to join, adding that this will be a valuable opportunity for students interested in solving a real-life space problem: that of keeping astronauts fed and happy on other worlds.

“Somewhere, someone holds the answer to plant and soil viability — and our ExoLab space farmers are going to find it,” she said. 

This biweekly column by Canadian science and space journalist Elizabeth Howell focuses on a trending news topic in Canadian astronomy and space.