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The ROSE experiments on the EXPOSE facility of the ISS

07/2001; 496:383-388.

ABSTRACT EXPOSE is a multi-user facility to be mounted outside of the
International Space Station (ISS). The tray-like structure will
accomodate among others 6 biological PI-experiments or experiment
systems of the ROSE (Responses of Organisms to the Space Environment)
consortium. EXPOSE will support long-term in situ studies of microbes in
artificial meteorites, as well as of microbial communities from special
ecological niches, such as endolithic and evaporitic ecosystems. Each
compartment is either vented, i.e. open to space vacuum, or sealed and
then provided with a defined gas environment. The experiment pockets
will be covered by an optical filter system to control intensity and
spectral range of solar UV irradiation. To achieve maximum insolation,
EXPOSE is mounted on a coarse pointing device. Control of sun exposure
will be achieved by use of shutters. EXPOSE has been selected for the
Early Utilisation Period of the ISS and will stay in space for 1.5
years. The results will contribute to our understanding of
photobiological processes in simulated radiation climates of planets
(e.g. early Earth, early and present Mars, and the role of the ozone
layer in protecting the biosphere from harmful UV-B radiation), as well
as studies of the probabilities and limitations for life to be
distributed beyond its planet of origin.

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