The ABS (Autonomous Biological System): Spaceflight Results from a Bioregenerative Closed Life Support System

Materially-closed aquatic life support systems containing vascular plants, invertebrate animals, algae and microbes were tested in three space flight experiments with ground controls. Termed Autonomous Biological Systems (ABS), the 0.9 liter systems were completely isolated from spacecraft life support systems and cabin atmosphere contaminants, and needed minimal intervention from astronauts. The first experiment, aboard the Space Shuttle in 1996 for 10 days, was the first time that aquatic angiosperms were successfully grown in space. The second and third experiments aboard the Mir space station had 4-month durations, in 1996-97 and 1997-98, and were the first time that higher organisms (aquatic invertebrate animals) completed their life cycles in space. Compared to the ground control ABS, the flight units showed clearer water and slightly higher total organic carbon and soluble free amino acids. ABS units from all 3 flights returned as diverse and complex ecosystems. The ABS are the first completely bioregenerative, closed ecological life support systems to thrive in space, demonstrating their efficacy for research in space biology and gravitational ecology.