Space hydrobiology

In addition to space exploration, manned spaceflights are aiming to prepare mankind to settle in space; however, the harsh, intense space environment poses an environmental challenge. Space hydrobiology as an interdisciplinary field that studies aquatic organisms and their ecological interactions can provide supportive measures in such situations. So far, studies can only be carried out in space for short periods, and though these studies have provided insightful knowledge, very few have reported on the impact of space conditions on aquatic organisms. Living in water their entire life, aquatic organisms have evolved many directional behaviors with obvious gravitational tropism, making them ideal models for space research. Additionally, aquatic organisms are ideal choices for the development of closed life support systems, and given their adaptability, they can serve as food sources for long-term manned flight missions. This chapter reviews the significance of aquatic organisms in space exploration and the biological effects of the space environment on these organisms to understand the fundamental biological mechanisms related to gravity and their potential to explore the outer space environment.