into the complex molecular machinery of graviperception, signal transduction and
movement control.
8.4 C.E.B.A.S.
In another approach a Closed Equilibrated Biological Aquatic System (C.E.B.A.S.)
was developed (Bluem and Paris 2001). This complex system consisted of
four components: A zoological component with fishes (Xiphophorus helleri) and
water snails (Biomphalaria glabrata), a microbial compartment with ammoniaoxidizing bacteria, a botanical compartment with the rootless, edible water plant
Ceratophyllum demersum and an electronic compartment for process control and
data acquisition. The underlying idea was that the plants harvest light energy and
produce biomass using photosynthesis.
The animals break down the biomass and produce carbon dioxide which is
utilized by the plants. The ammonia excreted by the animals is converted by the
bacteria to nitrite and subsequently to nitrate which is used by the plants as fertilizer.
The 150-L container was tested for more than 13 months. In addition, a C.E.B.A.S.
mini module was built (8.5 L). Due to space limitations there was no closed food
loop and the animals had to be fed by an automated feeder. This mini module was
flown successfully on the STS-89 and STS-90 space shuttle missions. The results
indicate that the plant biomass production was not affected by the space conditions
and that the immune system of the animals was not disturbed. In a later version the
small water plant Wolffia arrhiza was utilized which is consumed as vegetable in
Southeast Asia. The reproduction of the fish and snails functioned without problems
under space conditions for 120 days on the ISS in a mid-deck locker compartment
(Blüm 2003). However, harvesting of the various organisms had to be done by the
astronauts in order to avoid self-shading of the plants and excessive oxygen
consumption and ammonia excretion by the animals. The second problem was that
the animals had to be fed manually on a daily basis which demanded too much
crew time.
8.5 Eu:CROPIS
A new approach to the development of a regenerative live support system is the
planned Eu:CROPIS mission within the DLR compact satellite program (Hauslage
et al. 2018). A major problem in manned space flight is the processing of urine.
While water is recycled the dissolved substances (urea and salts) are discarded. The
new idea is to utilize urine as a fertilizer to grow fruits and vegetables using two life
support systems within the compact satellite Eu:CROPIS. This will be accomplished
by using a nitrifying trickle filter on a lava rock which houses bacteria, fungi and
protozoa. Euglena is used to produce oxygen and in addition, this flagellate can
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8 Bioregenerative Life Support Systems in Space Research
movement control.
8.4 C.E.B.A.S.
In another approach a Closed Equilibrated Biological Aquatic System (C.E.B.A.S.)
was developed (Bluem and Paris 2001). This complex system consisted of
four components: A zoological component with fishes (Xiphophorus helleri) and
water snails (Biomphalaria glabrata), a microbial compartment with ammoniaoxidizing bacteria, a botanical compartment with the rootless, edible water plant
Ceratophyllum demersum and an electronic compartment for process control and
data acquisition. The underlying idea was that the plants harvest light energy and
produce biomass using photosynthesis.
The animals break down the biomass and produce carbon dioxide which is
utilized by the plants. The ammonia excreted by the animals is converted by the
bacteria to nitrite and subsequently to nitrate which is used by the plants as fertilizer.
The 150-L container was tested for more than 13 months. In addition, a C.E.B.A.S.
mini module was built (8.5 L). Due to space limitations there was no closed food
loop and the animals had to be fed by an automated feeder. This mini module was
flown successfully on the STS-89 and STS-90 space shuttle missions. The results
indicate that the plant biomass production was not affected by the space conditions
and that the immune system of the animals was not disturbed. In a later version the
small water plant Wolffia arrhiza was utilized which is consumed as vegetable in
Southeast Asia. The reproduction of the fish and snails functioned without problems
under space conditions for 120 days on the ISS in a mid-deck locker compartment
(Blüm 2003). However, harvesting of the various organisms had to be done by the
astronauts in order to avoid self-shading of the plants and excessive oxygen
consumption and ammonia excretion by the animals. The second problem was that
the animals had to be fed manually on a daily basis which demanded too much
crew time.
8.5 Eu:CROPIS
A new approach to the development of a regenerative live support system is the
planned Eu:CROPIS mission within the DLR compact satellite program (Hauslage
et al. 2018). A major problem in manned space flight is the processing of urine.
While water is recycled the dissolved substances (urea and salts) are discarded. The
new idea is to utilize urine as a fertilizer to grow fruits and vegetables using two life
support systems within the compact satellite Eu:CROPIS. This will be accomplished
by using a nitrifying trickle filter on a lava rock which houses bacteria, fungi and
protozoa. Euglena is used to produce oxygen and in addition, this flagellate can
118
8 Bioregenerative Life Support Systems in Space Research