The space gardens
Is it possible to grow plants in space? The answer, though seemingly science-fiction, is yes.
Provide astronauts with the best living conditions in their spacecraft during long missions. This is the goal of Recyclab, the technological laboratory dedicated to research housed in the Turin plant of Thales Alenia Space Italia, founded to develop techniques for the generation and recycling of food and water directly in orbit and in zero gravity.
Food supplies are at presently shipped to the astronauts from Earth, if necessary; however, when more challenging missions of space exploration, such as those that relate to the Moon or Mars (which can last several years) start, it will be impossible to send into orbit everything scientists need for their stay in space. They will face the task of producing the substances necessary for their survival at the best possible conditions.
Thales Alenia Space has been studying food supply methods for years. Surprisingly enough, there are two watchwords that stand out: nature and recycling. During missions, in fact, once the initial stocks of food have been depleted, food must be produced through the recycling of waste and the cultivation of particular species of plants and bacteria.
Recyclab has for some time been working on EDEN, a mini space greenhouse, which is a refrigerator-sized container that allowed researchers to grow seedlings of lettuce on a substrate that simulates Martian soil. The small garden, illuminated by red and blue LED lights that use and reproduce the frequencies necessary for optimal plant growth by facilitating the natural process of photosynthesis, draws carbon dioxide from the surrounding environment and employs water obtained by condensing cabin air humidity. In fact, in addition to the independent production of food the other two objectives of the project are the renewal of oxygen and water purification, which is carried out by the absorption of roots and leaf transpiration.
In its ambitious path of development towards the ISS (International Space Station), EDEN will also stop in Antarctica, an extreme environment that will make it possible to replicate extreme operating conditions on Earth that in some respects are similar to those in space. This is the goal of the new EDEN-ISS project, funded by the European Commission, with an important Italian contribution from both the industrial and scientific perspective, coordinated by the German Aerospace Center, DLR, in Bremen.
According to the engineers of the “Life Support & Habitat” unit in Turin, the base in Antarctica will make it possible to faithfully reconstruct the isolated biological environment in close contact with humans, typical of a space station, thus testing the ability to produce quality foods under extreme conditions and studying management problems and difficulties, such as cleaning control. Indeed, we must suppose that the garden, even though it is in space and cultivated “out of ground”, will certainly not be a sterile environment and it will be necessary to reconcile its convenience with the high safety standards required in space systems.
These advanced research studies, developed for cultivation in extreme environments, will help significantly also on Earth, improving the yield and reducing the environmental impact of greenhouse crops, more and more widespread, with a more efficient consumption of light, water and waste. Space is an environment with limited resources where every gram is precious.
But not only. The compact portable greenhouse in orbit will also yield another benefit: harbour growing life and provide, therefore, a fundamental function of psychological support for crew engaged in long missions away from home.