MELISSA: 10 years of Research, Results, Status and Perspectives 2000-01-2378

Initiated in March 1989, the MELISSA (Micro-Ecological Life Support Alternative) has been conceived as a micro-organisms and higher plants based ecosystem intended as a tool to gain understanding of the behaviour of artificial ecosystems, and for the development of the technology for a future biological life support system for long term manned space missions, e.g. a lunar base or a mission to Mars.

The collaboration was established through a Memorandum of Understanding and is managed by ESA/ESTEC. It involves several independent organisations: IBP Orsay (F), University of Ghent (B), University of Clermont Ferrand (F), VITO Mol (B), ADERSA (F), University “Autonoma” of Barcelona (E), University of Guelph (CND). It is co-funded by ESA, the MELISSA partners, the Spanish (CIRIT and CICYT) and Canadian (CRESTech) authorities. The driving element of MELISSA is the recovering of edible biomass from waste (faeces, urea), carbon dioxide and minerals. Based on the principle of an “aquatic” ecosystem, MELISSA comprises 5 compartments from the anoxygenic fermenter up to the photosynthetic one (algae and higher plants). The choice of this compartmentalised structure is required by the very high level of space safety requirements and justified by the possibility to use an engineering approach and to built deterministic control strategy.

During the past 10 years a very progressive approach has been developed to understand and control the MELISSA loop. This approach starts from the selection of the microbial strains and higher plant crops, their characterisation and mathematical modelling, up to the demonstration on Earth, at pilot scale.

In this paper, we recall the main concepts of MELISSA, as well as the main objectives. A survey of the main results is presented and the main orientations are justified. At the end the new topics of research as well as preliminary development schedule will be exposed.