Even those of us with the greenest thumbs are baffled by the idea of growing food in Antarctica. From my tiny desk plant to my neighbor’s cabbage patch, plants generally have the same requirements: soil, sun and water. At the southern end of the planet, however, those are all scarce commodities. Nonetheless, on April 5, 2018, the team managing the EDEN-ISS greenhouse at Neumayer III announced that they had harvested 8 pounds of salad greens, 18 cucumbers and 70 radishes. This project has implications beyond just Antarctica, from moderate climates on Earth to future Mars missions.
What is the EDEN-ISS project?
Formally launched in 2015, the EDEN-ISS project is run by the German Aerospace Center (DLR). It’s made up of a consortium including representatives from academic and non-profit institutions, as well as several industry leaders. The project aims to design a bio-regenerative life support system (BLSS) that can be used for food production on the International Space Station and on future long-term manned missions to the Moon and Mars. This involves installing one cultivation system on the ISS and another in a specialized building in Antarctica. The system in Antarctica (referred to as Future Exploration Greenhouse, or FEG) should represent the challenges of setting up a base on another planet by requiring isolation from the outside environment.
Here on Earth, with manned Mars missions still far in the future, the project is thrilling the Newmayer III crew with the luxury of continuous fresh produce. However, as climate change continues destabilizing global agricultural practices, this research may prove beneficial in more moderate climates. Anything we learn about efficient use of resources could be crucial in the coming decades.
How does it work?
The FEG aims to move beyond the current state-of-the-art technologies to implement new solutions suitable for longer space missions. Soilless cultivation is considered mandatory for future missions, and EDEN-ISS is working on optimizing the yield for lower water and nutrient use systems. They’re also working to monitor ion concentrations and detect contamination in real-time.
Since reliance on sunlight is impossible, the FEG uses liquid-cooled LEDs to deliver photosynthetically ideal wavelengths to the plants in day/night cycles as necessary. Cooling the LEDs is necessary to keep the temperature stable (LEDs tend to produce a lot of heat when constantly active). However, their low energy consumption makes them stand out from other lighting options such as fluorescent or metal halide lamps.
The FEG is 1,312 feet away from the Neumayer III base, so the botanist tasked with managing the greenhouse must walk through the Antarctic weather to get there. If a particularly dangerous winter storm prevents him from getting there, the unit can be maintained remotely from Bremen, Germany.
How do they decide which crops to grow?
In the past, my gardens have been a haphazard selection of whatever I thought sounded tasty. If I was in the mood for carrots on the day I bought my seeds, then I planted carrots. For a garden with constraints as demanding as the FEG, crops must be strategically selected based on weighted criteria. The FEG is currently housing salad greens, cucumbers, radishes, strawberries, bell peppers, and several herbs.
A 2016 paper by part of the EDEN-ISS team described their methodology for choosing plants. Of course, a significant portion of the paper described the physical and biological constraints that limited selection. They mentioned that vegetables requiring little or no preparation are preferred, as well as those with the least wasted biomass. However, I was surprised to discover how much they stressed the importance of the taste and appeal of the crops. Food quality and enjoyment has a strong influence on psychological health, so longer missions must consider how much the crew will actually enjoy eating the resulting produce. For example, it has been found that the sense of taste is dulled by space flight and microgravity, so astronauts often wish for spicy food that won’t seem quite so bland.
To formally score the crops, the authors placed ten criteria into three categories (Yield, Cultivation and Quality) and weighed each category based on its relevance to the stated goal. For the Antarctica phase of the project, the goal was “the maximum amount of fresh food production, with a continuous daily flow of fresh food.” Thus, Yield was chosen as the most important category and weighed appropriately. The criteria in that category focused on light efficiency, space/time efficiency, and the mass percentage of the plant suitable for consumption. Under these specifications, the highest scoring plants were Lettuce, Cucumber, Dwarf Tomato and Chives.
The harvest on April 5, 2018 was only the beginning of the season for the FEG. By mid-May, EDEN-ISS expects the system to be producing 8-10 pounds of produce every week. Paul Zabel, the botanist who tends the greenhouse, says that the first few weeks were marred by some technical issues and a fierce winter storm, but now everything is running smoothly. “We have learned a lot about self-contained plant cultivation in recent weeks, and it has become evident that the Antarctic is an ideal test environment for our research,” he says. Meanwhile, in space, the crew of the ISS has been harvesting mizuna, red romaine lettuce and Tokyo bekana cabbage.
While the short-term results of the EDEN-ISS project are certainly interesting, the real challenge will come in the 2030s when NASA hopes to launch a manned mission to Mars. Such an expedition would take months, so a suitable BLSS must produce enough food to sustain the crew beyond the prepackaged rations. Then, someday in the distant future, perhaps the technology developed in Antarctica will be used to feed a base of permanent Mars residents.
To see more of the FEG and check out the harvest, visit the EDEN-ISS Instagram page.
Bamsey, M., Zabel, P., Zeidler, C., & Vrakking, V. (2016). Early Trade-Offs and Top-Level Design Drivers for Antarctic Greenhouses and Plant Production Facilities. 46th International Conference on Environmental Systems.
Cooke, L. (2018, April 05). Antarctic greenhouse celebrates their first harvest of lettuce, radishes, and cucumbers. https://inhabitat.com/scientists-harvest-the-first-ever-antarctic-vegetables/
Dueck, T., Kempkes, F., Meinen, E., & Stanghellini, C. (2016). Choosing crops for cultivation in space. 46th International Conference on Environmental Systems.
Zabel, P., Bamsey, M., Zeidler, C., Vrakking, V., Johannes, B., Rettberg, P., . . . Romberg, O. (2015). Introducing EDEN ISS – A European project on advancing plant cultivation technologies and operations. 45th International Conference on Environmental Systems.
First harvest in the Antarctic greenhouse EDEN ISS. (n.d.). http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-11008/1797_read-26679/#/gallery/30077