Feeding the Future for Light-Years to Come
Mars. After the Moon, it’s the next milestone in space for humankind. Plans are already in motion for the first manned missions. But the biggest stumbling block remains the amount of time, mass and energy it will take to get there. A mission to Mars means a thirteen to eighteen month round trip. Astronauts won’t be able to rely on supplies from back home or an in transit re-supply to keep going. Instead, they’ll need to grow their own food in space.
I’m currently in my final undergraduate year studying environmental science at the University of Guelph, working to advance the bio-regenerative life support system for use in space. Cultivating plants on future space missions isn’t just a matter of providing food for astronauts; it could form the basis of an entire on-board life support system. Plants produce oxygen and filter out carbon dioxide, so in an enclosed space they are an effective atmospheric regulator. Plants are also are great at filtering out grey-water and supplying us with clean, potable water. On top of that, there’s a fantastic psychological benefit to interacting with another living organism within an enclosed area. We’ve already seen this on missions to the International Space Station (ISS), where the astronauts are known to have jostled for position over whose turn it is to do the greenhouse experiments! On a 55 million kilometer journey, caring for a little piece of greenery could go a long way to helping Mars pioneers adjust to life in space.
Supported by the Bayer Foundation’s Jeff Schell Scholarship, I recently spent eight months in Bremen, Germany, working with the DLR Institute of Space Systems EDEN Initiative under Dr. Mike Dixon (Guelph), Dr. Thomas Graham (Guelph), Dr. Matthew Bamsey (DLR) and Daniel Schubert (DLR). Here they work on bio-regenerative life systems in space. In practice, this meant spending my days in a 12 meter-long customized shipping container – EDEN ISS – which is used for controlled environment agriculture; to simulate what it would like to grow plants on the surface of the Moon or of Mars.
Here I gained hands-on experience testing a new Canadian-made technology known as ‘ion-selective optrodes’. Looking to improve on the operation of a high-performance liquid chromatographer, these are sensors that can be integrated into the aeroponic nutrient delivery system and will instantly measure the level of dissolved minerals within. Without being able to control how much nitrate, calcium, or phosphorous is in a solution used to nourish plants, there’s a strong possibility that the plants might not make it, that they’ll over-consume nutrients, or that they’ll under-produce biomass. Currently, the system is being tested at the Neumayer-III station in Antarctica: the closest, most remote place on Earth with conditions similar to what we might find on Mars.
The work being done in this field isn’t just useful for future space missions. Everything we learn in space can be applied to situations back on Earth. This has always been the case: from laser targeting tested on the International Space Station (ISS) and then applied to corrective eye surgery, to the microprocessors first used in on-board computers which are now ubiquitous in our smartphones. When it comes to agriculture, for example, learning how to maintain controlled growing environments in the depth of space will give us the know-how to improve terrestrial production techniques and completely close the air, water and food loops back home. Suddenly, people in sparse natural environments such as the Canadian Arctic or the Saharan Desert could have easy affordable access to fresh produce.
Of course, there’s still a long way to go. The biggest challenge we currently face is how heavy and energy-intensive the necessary support systems are. Right now, we would need about 50 m2 of growing area to support just one person indefinitely. On top of that, we’re still learning to deal with the impact of microgravity on plant growth and its genetics. On Earth, gravity acts on certain starch molecules in a plant’s roots, pulling them down and essentially telling the plants which way is up. But when the force of gravity is reduced in space, the plant can’t orient itself! Luckily plants are like people, with more than one sense. Thanks to work done on the ISS by Dr. Anna-Lisa Paul and Dr. Robert Ferl from the University of Florida, we’ve found that if gravity isn’t going to do the work, you use light instead: specifically, LED lights, since sunlight isn’t an option. Put these above the plants and, even in microgravity, they will grow upwards, drawn towards the light.
Feeding the Future for Light-Years to Come
This example encapsulates why space science is a really creative, exciting field to be working in right now. Getting up every day and doing something to advance the human race to such an extent is extremely rewarding. I didn’t personally fully grasp the potential of space science until a few years ago, when Canadian astronaut Chris Hadfield went on his most recent mission to the ISS. He sent a message to Canadian youth: if you try hard enough, you too can quite literally reach these same heights! And then of course when Hollywood blockbuster ‘The Martian’ was released – a relatively accurate film from a scientific perspective – it just made me even more certain about my choice of career.
I don’t think the excitement around space exploration has been this high since the Apollo missions. With the emergence of the commercial space industry, and the slow decrease in technology costs, we’ll soon reach a point where humans colonizing Mars moves from the stuff of science fiction to reality. A few years ago, I’m not sure I could have envisioned a career in this sector; now the opportunities are endless. I might not ever get to personally set foot on the Red Planet (although you wouldn’t have to ask me twice if I had the chance!), but perhaps my children will. And in the meantime, I’m going to keep working in the area of plant science, for on and off the Earth.
After all, these plants are what will keep us alive on the other side of the solar system. And who knows; perhaps, one day, they’ll take us even further.