Bioregenerative life support systems
As the basis of bioregenerative life support systems, a simple ecosystem is being recreated whose key is the transfer of essential fatty acids from algae to higher animals via zooplankton. Therefore, it is important to develop methods that allow zooplankton to live in micro or gravity-free environments.
Gravity, as a permanent constant, exerts a strong influence on the evolution of all organisms. Thus, a wide range of gravity perception systems is also known in aquatic organisms, although there is still little research on zooplankton in this regard. Gravity is the only way for plankton organisms to orientate themselves under limited visibility conditions (water turbidity, darkness). In this context, research into the influence of altered gravitational conditions (microgravity and hypergravity) on aquatic organisms is located, which should help to subsequently develop a model for a bioregenerative life support system. In a first step, the relevance of gravity on the behaviour (gravitaxis) and life cycle parameters of the experimental organisms will be tested. One focus is on the model organism Daphnia, since both the gravity-perceiving organs have not yet been fully elucidated and the influence of gravity on the formation and reactivation of the permanent stages has not yet been researched.
The water flea Daphnia magna (left) and the ostracod (top right) used in ecological experiments (bottom right) to study the influence of microgravity on different model organisms.
From left to right: Launch of a TEXUS research rocket, A300 ZERO-G parabolic aircraft, experiment on swimming behavior in microgravity during a parabolic flight, Alexander Gerst and Samantha Cristoforetti with parts of an experiment hardware.
From left to right: The drop tower in Bremen, experiment in a drop capsule inside the Bremen drop tower, parts of the experiment hardware from the drop capsule, Random Positioning Machine for simulating microgravity.