Manned space missions lasting several weeks or even months will only be possible if transporting the astronauts’ provisions does not take up too much of the spacecraft’s energy. One solution to this problem may lie in organisms that produce essential nutrients on board. Is the answer to be found in water fleas that produce large amounts of biomass here on Earth? Biologists at the University of Bayreuth have developed experiments to test the behavior of these animals at zero gravity. These experiments have now been completed successfully on a suborbital flight carried out by the privately funded company Blue Origin. They were among the first biological experiments to be carried out on a Blue Origin flight.
Life support systems in outer space: researching astronaut food of the future
Zooplankton are tiny organisms that represent an important link in the food web of our lakes and seas: on the one hand, they feed on micro-algae, and on the other hand, they serve as a nutritious food for fish and other aquatic animals. The largest proportion of zooplankton are tiny crustaceans that are vitally important from an ecological perspective due to the biomass they create. Such organisms include in particular water fleas (Daphnia). “Many years of research with these organisms gave us the idea that they also could produce biomass in space and thus make an important contribution to astronaut food,” explained Prof. Dr. Christian Laforsch of the University of Bayreuth.
These considerations arise in the context of biogenerative life support systems (BLSS), which scientists around the world are working on with ever-increasing intensity. Such systems are artificial ecosystems that are supposed to serve as a permanent and reliable supply of nutrients for humans – not only in outer space, but also in areas afflicted by food shortage.
The latest research carried out by scientists in Bayreuth is groundbreaking in this area. Doctoral researcher Jessica Fischer recently demonstrated in the journal npj Microgravity that other zooplankton organisms, in this cases ostracods, are also well-equipped for nutrient production in a BLSS, even at zero gravity.
Zero-gravity experiments: successful cooperation with Blue Origin
Now for the first time, during an unmanned flight conducted by the American company Blue Origin, it has been tested how zero gravity affects molecular processes in the water fleas. “These effects must be known before one can use the organisms in life support systems. We are therefore very pleased that we were able to make significant progress in our research with the support of Blue Origin,” said Dr. Miriam Knie, biologist at the University of Bayreuth who witnessed the launch of the rocket New Shepard in Van Horn, Texas on 29 April 2018. Named after the first American to travel into space, the aircraft was employed by Blue Origin for the project “Scientific Pathfinder Flights”, funded by the German Aerospace Center (DLR). The project is expected to facilitate scientific experiments in outer space – especially investigations that contribute to future developments in manned space flight. This was one of the reasons the Bayreuth experiments were selected.
New Shepard landed safely approximately eleven minutes after lift-off. “In the coming weeks, we will carefully evaluate the data collected at zero gravity and compare it with our previous research results in Bayreuth. We will then have a better idea of just how well-suited Daphnia really are for use on space stations or during extended travel through outer space. We will present our findings to the public as soon as possible,” said Dr. Knie.
New findings regarding food supply on Earth
The biologists in Bayreuth are optimistic that the new measurement data will prove to be instructive with a view to further research questions. For example, to date little is known about how biological systems that are sensitive to gravity developed in the course of evolution. “But above all the experiments in space are designed to give us an understanding of the extent to which plankton organisms can be used – also on Earth – for a sustainable food supply,” explained Prof. Dr. Christian Laforsch.
Full bibliographic information
Jessica Fischer and Christian Laforsch: The influence of gravity and light on locomotion and orientation of Heterocypris incongruens and Notodromas monacha (Crustacea, Ostracoda), npj Microgravity 4, 3 (2018).