Agricultural scientists are experimenting with growing food in space and some experts believe this could give rise to more sustainable methods of producing food at home.
Space travel may sound totally unnecessary but many inventions have resulted in great new products such as cordless tools and water filters to name just two. Now food is benefitting from humans going into space Well-known products that NASA claims as spinoffs include memory foam, freeze-dried food, firefighting equipment, emergency “space blankets”, DustBusters, cochlear implants, LZR Racer swimsuits, and CMOS image sensors.
For humanity to establish a self-sufficient presence beyond Earth, we must work out how to feed ourselves on other planets. Unfortunately, no other celestial body known to scientists is blessed with the same advantages for life as the blue marble we call home. From generating soil to pollinating crops, Earth’s ecosystems provide a bounty that has nurtured our evolution and made complex societies possible.
Most modern farming systems take this generosity for granted. At every stage of an industrial agriculture operation, Earth’s seemingly inexhaustible capacity to provide is exploited. Vast quantities of factory-made fertilisers and pesticides coax solitary crops from vast acres of land, then the produce is packaged in refrigerated containers and distributed via global supply chains. Despite increasing evidence to the contrary, the assumption appears to be that our planet will continue to absorb the waste, pollution and habitat destruction in perpetuity.
Now, though, agricultural scientists are experimenting with growing food in space, where crops must do without warmth, water and soil and contend with zero gravity and radiation, among other hazards. And some experts believe that being forced to do without Earth’s gifts will give rise to more sustainable methods of producing food at home.
You’re reading the Imagine newsletter – a weekly synthesis of academic insight on solutions to climate change, brought to you by The Conversation. I’m Jack Marley, energy and environment editor. This week, we’re discussing how the challenge of feeding space travellers will benefit life back on Earth.
“After ‘washing’ the lettuce with sanitised wipes, the astronauts first tried their salad plain, then added a little olive oil and balsamic vinegar to bring out the flavour,” writes Tanya Hill, an astronomer at the University of Melbourne in Australia. Hill is describing the first meal ever grown and eaten in space: a romaine lettuce produced on the International Space Station 400km above Earth in 2015.
“In space, astronauts use aeroponics to grow their garden,” Hill explains. “The plants are grown mostly in air, with just a very small amount of nutrient-rich water. Sunlight is provided by a bank of red, blue and green LED lights.
“The plants actually gain enough energy to grow from the red and blue lights alone — but this makes the lettuce a weird purple colour. Green LED lights, which are less efficient, were added to make the lettuce more attractive to eat. It’s a little known fact that sunlight peaks in green light,” she adds, meaning the sun gives off mostly green light in the visible spectrum.
Growing enough food to feed a Martian city would require another giant leap. Lenore Newman and Evan Fraser are experts in food and agriculture at the University of Fraser Valley and the University of Guelph in Canada, and they have studied what’s necessary to make this a reality.
On the red planet’s barren surface, scarce water, space, light and organic matter are ruthless arbiters of what can be produced. Detoxifying the Martian bedrock and freeing water frozen in the planet’s crust will be the first necessary steps. For that, Newman and Fraser say, microscopic cyanobacteria (or blue-green algae) can help – their growth releases nutrients and breaks down minerals into a rudimentary soil.
Next, advanced greenhouse technologies – such as vertical agriculture, where crops are stacked under LED lights – will produce leafy greens, fruits, vegetables and speciality crops like herbs, coffee and cocoa. Such methods would use a fraction of the space of conventional farms on Earth, and recycle the water.
“These technologies are also valuable on Earth as we attempt to shorten supply chains and improve the availability of healthy fruit and vegetables in the winter months,” the pair say.
Grains typically need a lot of farmland to grow, so the first Martian settlers may have to adjust to eating a different diet. What else is off the menu?
“Animal agriculture is notoriously inefficient. On Earth, billions of domestic animals threaten natural biodiversity, contribute to climate change, and suffer from needless animal cruelty,” they add. But while sprawling cattle ranches are out, meat may not be. Newman and Fraser say that “precision fermentation” – a process which grows animal tissue in laboratories – could produce lots of protein in vats from modified yeasts, fungus and bacteria consuming simple starches and sugars in food waste.
“On Mars – where each gram of organic matter, millilitre of water and photon of solar energy is scarce – there can be no inefficiencies,” Newman and Fraser say.
“The ‘waste’ products of one part of the system need to be deliberately used as inputs into another part, such as using the dead cyanobacteria as a growth medium for later parts of the food system. But more than the technologies themselves, it may be the mindset of building a Martian food system that will change how things are done here on Earth, where one-third of all food is thrown away.”
As climate change shortens growing seasons and slashes crop yields, research conducted in space may help farms adapt, according to PhD candidate Ajwal Dsouza and assistant professor Thomas Graham, who both study environmental sciences at the University of Guelph.
“Researchers at Nasa sent cotton seeds to the International Space Station to understand how cotton roots grow in the absence of gravity. Their findings will help develop cotton plant varieties with a deeper root system to access and absorb water more efficiently from soil in drought-prone areas,” they say.
Adjusting food production to inhospitable conditions in space and on other worlds reveals the absurd amount of waste inherent in much of modern agriculture. But according to Michael Dixon, director of the Controlled Environment Systems Research Facility at the University of Guelph, it can also help farmers recalibrate food production according to Earth’s environmental limits.
“Today, we spend millions of dollars flying perishable food to Northern Canada, such as buying strawberries from Mexico for sale in Yellowknife. This doesn’t make sense,” he says. “For food production, space exploration will enable us to learn how to grow crops almost anywhere, and with as little impact on the environment as possible.”
Original source: Jack Marley, Environment commissioning editor, The Conversation