E-USOC (Spanish User Support and Operations Centre) is a centre of Polytechnic University of Madrid (UPM) specialized in Research and Development (R&D) activities in the fields of space science and technology. On behalf of ESA (European Space Agency), the centre offers the necessary assistance for the preparation, execution and post-flight analysis of space experiments to the Spanish scientific community.

E-USOC is the point of contact for the Spanish user teams developing experiments which require microgravity environment, such as the International Space Station, Space Shuttle missions, Parabolic Flights and so on. It is also the point of contact for European Users carrying out space experiments involving the payloads which E-USOC is responsible for (e.g., experiments concerning the Fluid Science Laboratory (FSL) onboard the International Space Station (ISS).

E-USOC also provides information and promotes activities in the field of space sciences and fluid mechanics, giving technical and operation support to researchers and investigation groups which want to carry out experiments in microgravity environments or in any field of research related to space science

The centre has been active for years in the aerospace field and its experience can be highlighted by the following projects:

• ESA’s Facility Support Centre (FSC) for the Fluid Science Laboratory (FSL) to be launched on board Columbus. From the FSC, FSL will be operated remotely. Besides, E-USOC will support European Scientists performing experiments onboard ISS in the Fluid Science disciplines and Spanish scientists in all scientific disciplines.
• The study of the behaviour of liquids under microgravity conditions. This is a research program started in 1974. Within this program a quite large number of experiments have been performed in space orbiting platforms (Spacelab Missions SL-1, 1983; SL-D1, 1985; SL-D2, 1993), sounding rockets (TEXUS 10, 1984; TEXUS 12, 1985; TEXUS 18, 1988; TEXUS 23, 1989; TEXUS 30, 1992 and TEXUS 33, 1994), aircraft parabolic flights and drop towers. Besides the high scientific content, this program also incorporates technological aspects: a module for experimentation with liquid bridges in simulated microgravity by using neutral buoyancy technique was developed for ESA/ESTEC to provide crew training in liquid bridges for several Spacelab experiments, and another module for liquid bridge experimentation was developed and flown for the Spanish Minisat-01 platform in 1996. Experiments on other disciplines have also been performed on crystal growth (TEXUS 29, 1991) and, for education, on basic principles of mechanics (SSM on board ISS, 2003).
• Concerning the development of experimentation facilities, E-USOC personnel conducted together with CASA in the late 70s the definition study of the Fluid Physics Module (FPM), a facility later built by FIAT and flown in Spacelab several times. Other definition studies done by E-USOC were the Phase A of the Fluid Science Laboratory in the mid 80s and TRPs in the frame of the High Temperature Facility Technology Study together with the NLR in the Netherlands.
• In the field of Telescience, E-USOC designed and manufactured for ESTEC a remote controlled Plateau Tank Facility which was integrated in the Telescience Test Bed in ESTEC to evaluate the impact of Telescience in operations with a “real” microgravity fluid science experiment.