In order to carry long-term manned space exploration, closed-loop life
support systems are developed at ESA to enable recycling of wastes into
oxygen and food. These systems involve the use of regenerative processes.
Two studies are presented in this framework. The first one concerns the
development of an experiment to be flown onboard the International Space
Station. It aims to assess the space environment effects on a micro-organism
involved in an oxygen recycling process of a life support system, as well as
in the food chain.
It also aims to assess relevant technologies to maintain the culture and
monitor measurements, which has not yet been done for a space application.
It features as well an educational part to teach a group of European
students about life support systems. The steps to reach the final design are
presented, on both technical and procedural points of view. A set of
requirements is being defined, and a first draft design is presented for a
feasibility study. It involves a hardware description of a photobioreactor
together with its flight support equipment, and an associated flight
procedure. It is evaluated considering constraints imposed by the Science,
the crew availabilities, the resources for implementation and potential
interfaces, the safety aspects. Knowledge of such
constraints is continuously updated through frequent meetings with each of
the
parties involved. A set of three papers has been written in the frame of
this
preparation. After approval of the mission feasibility, contact is undergone
with
a contracting company to develop a deepened comprehensive preliminary
experiment design. Its status follows imposed requirements, advices, and is
closely followed up. It is presented up to Preliminary Design Review level.
The
assessed design at the Review's output still requires a short size and mass
shrinking for implementation due to Soyuz module transportation constraints,
and would then be ready for manufacturing and testing.
The second study regards the case of lunar life support systems for manned
exploration. It is envisaged in the long term to have a permanent outpost at
the
South Pole of the Moon, where settlers will be supported by greenhouse
cultures. A precursor unmanned mission known as MoonNEXT is to be flown in
the next few years to investigate a potential landing site. It will feature
a small
coupled bacterial system on top of a Lander as a lunar life support
experiment.
In both cases of greenhouse and small experiment, knowledge of the available
light at the landing site is crucial to size the system. A numerical tool to
assess available light at potential landing sites is asked to be developed.
It is
programmed with Excel and its Visual Basic coding possibility. The model has
two inputs: a date and a lunar site among four possible, selected based on
previous studies. It first calculated the solar flux reaching the Moon at
the given date using orbital dynamics. It then considers the topography
surrounding the selected site and assesses if it is susceptible to hide the
solar disk. This step is based on a comparison between a solar elevation
model (built for the occasion) and a terrain elevation model (using
available data). A comparative study of available illuminatio...
