ISS-VIEW - A SOFTWARE POOL FOR EXTERNAL SCIENCE PAYLOADS ATTACHED TO THE INTERNATIONAL SPACE STATION

In the framework of the Agreement for the Early Utilisation of the Int ernational Space Station (ISS), ESA has negotiated with NASA to have e arly flight opportunities for European payload instruments prior to th e launch of the Columbus Orbital Facility, in exchange for the deliver y to NASA of a set of items that constitute the early European contrib utions for the utilisation of the International Space Station. One of these early European contributions is the Hexapod positioning/pointing system, which is being developed under the responsibility of ESA's Di rectorate of Manned Spaceflight and Microgravity to provide a pointing platform for the NASA Stratospheric Aerosol and Gas Experiment III (S AGE III) instrument. Hexapod and SAGE III are designed to be accommoda ted on an ISS Express Pallet and have a five-year design lifetime. The y will be launched with Space Shuttle flight UF-4 at the beginning 200 2. The ISS-VIEW software tool has been developed to support the missio n analysis and to define the observational windows for Hexapod/SAGE II I, but it can also be used for other instruments. for example, it also allows one to predict astronomical or Earth-target observing opportun ities for Express Pallet payload instruments from their actual mountin g locations on the Space Station Truss. In addition to the orbital and attitude parameters of the Station, ISS-VIEW is also able to take int o account the field-of-view restrictions imposed by both the fixed and movable elements of the overall Space Station assembly.