Scientific research is mandatory for all SSD scientific staff. The Department therefore maintains a research infrastructure and environment. These facilities are also used by ESA Research Fellows, trainees and scientific visitors hosted by SSD. Engineering and technical staff and system managers provide the necessary laboratory and computing support.
Research performed in the Department ranges from science- technology developments (such as detectors), through the design, construction and testing of actual flight instrumentation, to the analysis of measurements and observations. The latter are obtained with instruments developed in-house or with external spaceborne or ground-based facilities.
Major advances can be reported in the development of superconducting tunnel junctions (STJs). These detectors promise to become the device of the future: their band-width ranges from X-rays, through UV and into the IR, and they measure the photon energies of the received radiation - all done at high efficiency. Arrayed STJs are set to become highly efficient slit- and dispersion-less imaging spectrometers.
In the past 2 years, ten instruments developed by SSD within international consortia have been delivered in preparation for their launches. For Cluster, two sets of four instruments each (EFW Electric Field and Wave; ASPOC Active Spacecraft Potential Control) were integrated and tested on the spacecraft. For the Huygens Probe that is to descend through Titan's atmosphere, the Huygens Atmospheric Structure Experiment (HASI) and the Surface Science Package (SSP) - both the result of extensive international collaborations - have been completed and delivered for integration and further testing on the Probe. Following the Ariane 501 launch failure and approval by the SPC, the fifth model of both Cluster experiments was prepared for integration on the refurbished spare Cluster spacecraft 'Phoenix'.
Experiment developments underway for launches in the coming years concern an energetic particle experiment for the German Equator-S small satellite, and a dust counter for the Japanese Planet-B technology mission.
Data obtained from SSD-related instruments during 1995-96 on Ulysses, the Japanese/American Geotail, the Russian Interball and on NASA's Polar, Wind and Compton Gamma Ray Observatory missions were available for exploitation. Following the launches of SOHO and the Italian-Dutch SAX, helioseismology and soft X-ray data also became available.
The results obtained by SSD staff from these experiments and from observations on other space- or ground-based telescopes - among them most recently the Infrared Space Observatory - are regularly reported in the refereed literature.
Proposals for SSD participation in the development of five instruments for flight on the Rosetta comet rendezvous mission were selected. The most remarkable among these is an atomic force microscope for imaging sub-µm dust particles.
First steps were also taken in research for Fundamental Physics missions. This research was actually required as part of the preparation for future missions and concerned the integrity of measurements. This included the error analysis of a projected Equivalence Principle experiment the evaluation of drag-free attitude control systems, of the charging of test masses and of the stability of rotating experiments.
In summary, SSD research has continued over the past 2 years on a broad front. In many cases this is the result of collaborations with scientists in ESA's member countries. This practice ensures that the dialogue between SSD's staff and the community at large takes place not only in study and project work, but also in the context of actually solving the scientific problems that are the basic motivation for ESA's Scientific Programme.
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