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The space environment (i.e. cosmic rays, radiation belts, solar energetic particles, plasmas, outgassing and micro-particles) poses many threats to spacecraft and astronauts. The Space Environment Information System (SPENVIS) is a web application that provides models and tools to space engineers and scientists to model the space environment around Mercury, Earth, Mars and Jupiter but also in the interplanetary medium. In addition, it allows the users to combine and chain results between different models enabling them to calculate the potential effects of the environments specific for their (planned) mission. The effects are divided in the following categories: ionizing dose, non-ionizing energy loss, radiation damage in solar cells, single event upsets, spacecraft charging, atomic oxygen erosion, and meteoroid and debris models. Since SPENVIS’ introduction in 1996, the informatics technology has evolved considerably. In the last part of this paper, SPENVIS Next Generation is presented. The framework has been reviewed, restructured and reengineered using current web design techniques and programming methodologies, providing a new, extensible and distributed framework for the integration of current and future space environment models.

In preparation for deployment of the Galileo satellite navigation system, Europe has launched a test satellite, Giove-A. One of its objectives is to measure the radiation environment encountered in medium Earth orbit (MEO) which is a new regime for European missions. Giove-A therefore includes two radiation environment monitors: Merlin supplied by QinetiQ and CEDEX supplied by the University of Surrey. Merlin measures electrostatic charging and electron fluxes, total ionising dose, energetic proton fluxes and heavy ion linear energy transfer (LET) spectra. CEDEX monitors energetic proton fluxes, heavy ion linear energy transfer (LET) spectra and ionising dose rates. Giove-A, which was built by SSTL (UK), was successfully launched on 28th December 2005 into a 23,600 km circular, 56 degree inclination orbit. Data received since launch has been analysed and demonstrates that the MEO environment is highly dynamic due to the influence of space weather. Numerous electron belt enhancement events have been observed and the charging effects of these events been characterised. Total ionising dose is also seen to be delivered almost wholly during electron events.