One of the major hurdles in spaceflight is the supply of food, water, fuel, and oxygen. The distance that we can travel is limited by how much we can carry. The International Space Station (ISS), orbiting about 200 kilometers above the earth relies on regular shipments of fuel and other supplies. But a satellite orbiting above the moon or a colony on Mars cannot rely on supplies from earth.
In what could be a step toward solving the problem of sustainability, scientists are trying to develop a technology called artificial photosynthesis, a way to harness sun’s light for the generation of fuel and oxygen. This is essentially similar to the natural photosynthesis, where plants convert sunlight into energy and release oxygen as a byproduct.
Researchers successfully performed photo electrochemical experiments in a microgravity environment. These involve reactions that use light and electrical properties of chemicals. Katharina Brinkert, a chemist at Caltech and her team conducted a successful experiment to create light-powered, fuel-producing chemical reactions inside the Fallturm Bremen, a Drop Tower in Bremen, Germany. This facility simulates the microgravity conditions of an orbiting satellite.
“Doing electrochemistry is already difficult,” Brinkert said. “Doing it in microgravity is even more difficult.” Thankfully, the experiments were a success, and Brinkert and the team were able to produce hydrogen gas, a source of fuel from a water-based acid solution. This has the potential to be a sustainable fuel source for long distance space travel.