VIBRA DAMP  For experiments which are reliant upon a high microgravity quality this residual accelerations can still be too much. This is where our experiment comes into play. Our goal is to develop a assively damped experiment module for REXUS which will isolate a major part of the forces acting on the damped system. The idea is based on an award-winning diploma thesis from a former student (Manuela Franke) of the Aachen University of Applied Sciences. The thesis dealt with the possibility of passively dumping the TITUS melting furnace inside the MIR space station.   We will create a lightweight case which will fit into a REXUS standard module. During the zero-g period the only connection between the outer structure of the rocket and the damped case will be some small beam-springs. The contactless damping is based on the eddy current principle (e.g. known from the braking system of the ICE highspeed train). A permanent magnet is located in front of a plate build of an electrically conductive material, without permanent magnetic attributes.   When the magnets moves relatively to the plate, a current is inducted into the plate. The current creates an own magnetic field which acts against the original movement. This construction will make it possible to build a system with very low eigenfrequencies so that most of the stimulating forces will have a much higher frequency and because of this the system will be nearly entirely isolated from the forces acting on it. First rough calculations show that it is possible to create a system with an eigenfrequency of under 1Hz which could isolate about 95% of the forces acting on the damped system. To verify the expected results we will insert two seismic acceleration sensor packages into the REXUS module. One package will measure the acceleration within the damped system, the other will be connected to the surrounding structure.   The position and number of springs and magnets strongly depends on the mass and mass distribution of the damped experiment. As we want to create a damping system for integration of other experiments, it is not enough to create only a case in which the experiment can be connected mechanically but we have to create software tools for spring length, thickness, number and position calculation. For the damper calculation analogical software will be used.   Another important point is to create a locking mechanism which will keep the inner structure in the same position during start and landing. This mechanism has to prevent movement of the case to avoid plastic deformation of the extremely tender springs and more important to circumvent the destruction of the rocket during the start because of a free flying device inside of it.    Team: Rudolf Vetter, Andreas Gierse, Michael Lauruschkat, Lysan Pfützenreute: FH Aachen, Germany BUGS - Boom for University Gravity-Gradient stabilized Satellites The proposed experiment is the deployment of a satellite boom for gravity gradient attitude stabilization. This boom is based on a new concept exploiting rigidity properties of tape coiled spring. Due to the new technology, it has never been tested before in spaceflight conditions and ESA REXUS 7/8 campaign could provide an unique opportunity to analyse boom behaviour in operative conditions. The experiment will permit to achieve data on vibrations, shock levels and modal shapes of the boom during the deployment phase. Idea is to use this boom on board UNISAT-5 microsatellite, if proposed experiment for REXUS will succeed. UNISAT-5 is the fifth one of a series of university microsatellites manufactured by students, researchers and professors of the Group of Astrodynamics of the School of Aerospace Engineering of University of Rome “La Sapienza”. Demonstrating the possibility to exploit this boom for low cost satellites could be very useful for education and university satellites such as UNISAT ones. It could provide these satellites with nadir pointing attitude by mean of simple passive stabilization, permitting them to carry on a number of different experiments involving Earth observation. In this way these low cost satellite class could improve its scientific applications.   Team: M. Libera Battagliere, Chantal Cappelletti, Fabrizio Paolillo, Emanuele Paolini, Matteo Meschini: Scuola di Ingegneria Aerospaziale, University Sapienza of Roma, Italy Jacopo Piattoni: Alma Mater Studiorum, University of Bologna, Italy Website: http://www.bugsteam.com MONDARO - Measuring of neutral-gas density in the atmosphere by rocket The MONDARO experiment comprises three identical Pirani gauges mounted on the same ram deck of the payload. One gauge to be placed on the symmetry axis of the payload and the other twosensors has to be symmetrically mounted behind the shock front. Pirani is a sensor that utilizes thermal conductivity principle for gas density measurements. The measurements of the central gauge will yield the first successful high-resolution density measurements using a costeffective rocket-borne instrument. The measured densities of the neutral atmosphere will then be integrated assuming hydrostatic equilibrium, yielding the temperature profiles. An aerodynamical correction factors have to be applied to the density measured inside the gauges because of the shock front that arises due to the high speed of the sounding rocket. For the central sensor placed on the symmetry axis of the payload, these factors have to be calculated using the direct simulation Monte Carlo technique (DSMC). Comparison of the measurements made by the central sensor with the side-mounted ones will yield an experimental ram correction factors for suchhardware configuration. These experimental ram correction factors can further be compared with the factors calculated using the DSMC.   Team: Dörte Petzsch, Robert Püstow, Ralf Steinwehr, Robert Matschos: University of Rostock, Germany Robert Barth Websites: https://sites.google.com/site/teammondaro/home or http://groups.google.de/group/mondaro/web/rexus-07