Earth is the cradle of humanity, but one cannot remain in the cradle forever.Father of Rocketry – Konstantin E. Tsiolkovsky.
Humankind has always believed in the presence of life elsewhere, and the next logical step will be space exploration and possible terraforming of other plants. Two Voyager spacecraft carrying a Golden Record of life have reached further than any manmade objects in space 1. Meanwhile, different nations, scientists, and organizations are preparing for manned space exploration. With rapid technological progress and efforts in space research and exploration by organizations like NASA, SpaceX, Blue Origin, and many others, the days of space tourism and interplanetary travel is not too far.
Since the launch of the Soviet Union’s Sputnik 1 into space, the horizon of space exploration has expanded, and with the constant breakthroughs in the processing power of computers, it is convenient to point to the possibilities of traveling far from earth. Technologically, it is possible to launch a spacecraft capable of traveling a great distance, and scientists have figured out ways of providing essential supplies to crew members for an extended time periods. While processed foods, vitamin supplements, water recycling, and producing and recycling oxygen onboard a spacecraft are sufficient for survival of the crew, long term travel can be problematic.
In 1946, maize seeds were launched in space in an attempt to study the effects of radiation on biological materials, which was followed by several biological spaceflight research 2, most notably the Salyut 7’s experiment growing Arabidopsis (Rockcress), the first plant to flower and produce seeds in space. Consequently, there has been several significant research in plant biology and food production in space. The experiments are not exactly cheap, and it begs a question, “Why not just use packaged foods, which are much more convenient than growing foods in space?”.
All of it comes down to the fact that future space travels might take years or longer. With such a stretch of time, the nutritional quality of packaged food degrades significantly, and fresh foods will bridge the gap in nutrients 3. With plants growing aboard spacecraft, it is also easier to recycle atmosphere and recycle wastewater to make it drinkable.
Furthermore, being away from earth can adversely affect crew members, leading to anxiety, depression and other psychological problems. Just like people resorting to gardening during the global pandemic for mental well-being, it is predictable that the presence of fresh greens will help astronauts cope with isolated conditions, which is crucial for the well-being of crew members and the space flight missions.
Microgravity often refers to the condition where the force of gravity is very small and far smaller than what we experience on earth’s surface. While the presence or absence of gravity can hugely impact natural processes (including biological processes), the effects of gravity on such processes are often overlooked, mainly because natural processes are generally perceived on the earth’s surface where gravity is omnipresent.
In microgravity, everything behaves differently than on earth, so the way of growing plants is also different. Such behaviors pose complications in plant growth, like the possibility of suffocating roots in microgravity as water accumulates in a place rather than flowing down. Additionally, plants perceive the absence of gravity as stress and are more susceptible to microorganisms in the absence of gravity 4.
To address such issues, special growth chambers have been developed for growing food in space, complete with artificial lights, sensors, fertilizer supply, and a controlled environment. The most notable ones are NASA’s Veggie and Advanced Plant Habitat (APH) aboard the International Space Station, which have been aiding in space plant research 5. Recently, a research team at the University of Florida demonstrated successful germination of plants in lunar soil brought back from a series of Apollo missions, further increasing the understanding of plant biology in alien soils.
Recent advancements in short parabolic flights to study impacts of microgravity on plants, research onboard the ISS, involvement of the larger scientific community, and advances in genetic research are pushing forward the possibilities of space explorations. With companies like Jeff Bezos’s Blue Origin making possible space tourism, and SpaceX’s cost-efficient technology, and NASA’s research and collaboration with scientists and universities, it is safe to say that a self-sustainable space exploration will be carried out within a decade or two while growing plants in space or alien planets.