In a game-changing technological breakthrough, scientists are creating artificial photosynthesis devices that astronauts will use on future space missions.
On our lush and abundant planet Earth, the wide variety of plant species generously churns out all the oxygen our lungs crave. But once we step beyond the confines of our world, into the vast openness of space, such as the International Space Station or the lunar landscape, we’re left to fend for ourselves. Producing our own oxygen on space journeys becomes a critical necessity.
It is with this survival imperative in mind that novel devices are under active development, ones that seek to emulate the miraculous process of photosynthesis found in our plant kingdom. These devices ingeniously use sunlight and water to generate oxygen.
A collaborative study involving teams from the University of Warwick, the University of Bremen, and EPFL has provided encouraging evidence. The research, supported by the European Space Agency (ESA), indicates that these devices could potentially operate not only on the Moon but also on the harsh terrain of Mars.
As it stands today, electrolysis is the primary technique for extracting oxygen from water, but this method relies heavily on the availability of electricity. Taking a leaf out of nature’s book, these new devices work differently.
Coating semiconductor materials with metallic catalysts, these artificial photosynthesis systems create oxygen from water and sunlight, effectively sidestepping the need for electricity.
“Water has been detected on the Moon and on Mars. This study is a significant stepping stone in devising an alternative apparatus to supply future space explorers with fresh oxygen,” explained Brigitte Lamaze, an environmental control and life support engineer at ESA.
“Finding more efficient and environmentally-friendly ways to mimic parts of Earth’s atmosphere using available resources is a promising stride towards our goal of constructing a complete ecosystem within a box.”
“At ESA, we’re ceaselessly driving the limits of our theoretical knowledge in pursuit of superior technology. This study showcases one such leap in understanding the developments necessary for pioneering space technologies,” noted ESA engineer Christel Paille.
The research team has also performed calculations which suggest that artificial photosynthesis could be viable even on Mars, where sunlight is less intense due to the planet’s greater distance from the Sun. By deploying simple solar mirrors to focus sunlight, the oxygen production process could be significantly optimized and yield greater quantities.
“Years of intensive research lie ahead before we can harness this technology in space. However, emulating the crucial aspects of nature’s photosynthesis could offer us some distinct advantages. Our study has demonstrated that the theoretical foundations are robust,” explained Katharina Brinkert, a member of the University of Warwick research team.
“Space exploration is deeply tied to renewable energy and is thus intrinsically valuable for our energy transition on Earth,” said Katharina. “The lessons learned from designing and crafting these artificial photosynthesis devices could help address our green energy challenges on Earth. They could play a pivotal role in achieving our sustainability goals, both on our planet and beyond.”
This trailblazing research is published in the journal Nature Communications and can be accessed here. The study is part of a larger project funded by the Discovery element of ESA’s Basic Activities, initially proposed through the Open Space Innovation Platform (OSIP) in response to a call for innovative ideas on sustainable hydrogen production technologies.
Photosynthesis is a chemical process that plants, algae, and some bacteria use to convert light energy, typically from the sun, into chemical energy in the form of glucose, or sugar. This process is fundamental to life on Earth, as it is responsible for nearly all the oxygen in our atmosphere and forms the base of virtually all food chains.
Here’s a closer look at photosynthesis:
Photosynthesis takes place in two stages – the light-dependent reactions and the light-independent reactions, also known as the Calvin Cycle. The former occurs in the thylakoids (disc-like structures) of chloroplasts (organelles in plant cells responsible for photosynthesis), where light energy is converted into chemical energy. The latter occurs in the stroma (fluid-filled space) of the chloroplasts, where carbon dioxide is converted into sugar using the energy generated in the first stage.
These reactions occur in the thylakoid membranes of the chloroplasts. Here, sunlight strikes chlorophyll, the pigment that gives plants their green color, and excites its electrons. These excited electrons then pass through a series of electron carrier proteins in a process called the electron transport chain. This process generates ATP (adenosine triphosphate), the energy currency of cells, and NADPH (nicotinamide adenine dinucleotide phosphate), a powerful reducing agent.
The ATP and NADPH generated in the light-dependent reactions are used in the Calvin Cycle to convert carbon dioxide into glucose. This process occurs in the stroma of the chloroplasts and does not require direct light, hence the term ‘light-independent’. The Calvin Cycle involves several steps, including carbon fixation, reduction, and regeneration, which collectively result in the production of sugar.
Photosynthesis is critical for life on Earth for two main reasons. Firstly, it produces oxygen, a gas that most organisms need for respiration. Secondly, the glucose created in photosynthesis forms the base of virtually all food chains. The plants use this glucose for their own energy needs, and when herbivores eat these plants, the glucose is passed up the food chain.
Several factors can affect the rate of photosynthesis, including light intensity, temperature, and the concentration of carbon dioxide. In general, the rate of photosynthesis increases with light intensity and CO2 concentration, up to a point. Temperature can either speed up or slow down photosynthesis, depending on whether it’s within the optimal range for the plant’s enzymes.
Scientists are also working on technologies to mimic natural photosynthesis to generate renewable energy. This involves using sunlight to split water into hydrogen and oxygen, the former of which can be used as a clean fuel source.
To sum up, photosynthesis is an extraordinary process that sustains life on Earth, providing both oxygen and food. It is an area of intense scientific research, with potential applications ranging from combating climate change to powering our future in space.