Algal space food research. Bioreactor growing algae (green) for use as food in space. The light source fuels the growth of the algae. Algae-based foods are high in protein and energy. The algae would also provide a source of oxygen as it recycled the carbon dioxide in the atmosphere. This would be an essential part of a long-term, enclosed self-contained space mission. Photographed at the University of Nantes, France. The research is part of the MELISSA program of the ESA (European Space Agency).