The stresses imposed on organisms and communities living in extreme environments have led to the emergence of unique adaptation and survival mechanisms, that, if studied, can bring valuable new insights to our knowledge of biological processes, and could lead to the refinement of theories and the development of new ideas.
Several extreme environments on Earth bear similarities to extra-terrestrial planetary conditions, plausible for supporting life (cold or hot deserts, surface and subsurface habitats in Arctic and Antarctic regions).
Given the difficulties in accessing extra-terrestrial bodies, the study of these model systems on Earth can provide also important information in the preparation of missions that will search for life. This include direct signature of life (such as biomolecules) and indirect signals (such as geological modifications).
Another field of interest is represented by the effect of the space environment on terrestrial organisms (plants, animals and humans) to determine the feasibility of long space missions and providing the background knowledge for the development of complex life support systems.
Numerous studies have shown that as mission duration increases, the cost of supplying all consumables becomes unrealistic, and recycling becomes a necessity. In short-term mission a life support system may work as an open-loop circuit, while for long-term missions it is necessary to develop technologies which close the life support loop enabling a greater degree of self-sufficiency.
While it is possible to use physical methods alone to purify water and create oxygen from exhaled carbon dioxide, only bio-regenerative systems, involving plants, can produce food and thereby qualify as completely self-sufficient systems For this reason research is currently carried out on how to grow plants in space.
All physiological, biochemical and physical processes that are disrupted by the space environment can lead to reduced growth, premature death or malfunctioning organs, preventing the growth of plants in space for food production, and only with a global understanding of all these processes it is possible to define the parameters for their optimal growth.