The study of the high energy particle plasma outside the atmosphere, in the vicinity of our planet, has steadily improved in the last decades. The capability achieved by space experiments based on silicon microstrip detectors of identifying and tracing charged particles above few MeV, it allows the study radiation belt details not accessible before. The discovery of anomalous Cosmic Rays by the SAMPEX experiment or of quasi stable belts dominated by positrons of the order of GeV by AMS-01, are two examples of the accuracy achieved in these researches. The sensitivity achieved by modern experiments opens new frontiers in the study of the Earth magnetosphere characteristics and of its interaction with our planet. The magnetosphere properties determined, in fact, by the Earth magnetic properties. Modifications of the magnetic field would modify the characteristics of the magnetosphere, and correspondingly modify the physical observables, like the electric and magnetic fields as well as the properties of energetic particles trapped in the Earth magnetic field.Several study have shown, for example, that during a seismic event of adequate intensity, magnetic and electric perturbations are emitted and propagate in the surrounding space reaching the magnetosphere and creating measurable effects on the plasma. Other studies even suggest that a component of this perturbation could be emitted before (days/hours) the seismic event. These studies are supported by preliminary measurements done with satellites, suggesting a quite strong correlation between alterations in the Van Allen belt structures and terrestrial seismic phenomena.In this project, we propose the design and the construction of an instrument suitable to study this kind of precursor phenomena from the space, so that the existence of these effects could be established or discarded on scientific grounds.The proposed instrumentis a charge particle spectrometer, based on microstrip silicon detectors and scintillation detectors, able to determine with precision the flux and direction of charged particles trapped in the Van Allen belts, identifiying protons and electrons. This instrument would be capagle to measure in real time the dynamic of trapped particles and their variability in time. The spectrometer is also equipped with instruments to measure the electric and magnetic field variabilities from DC to 5 MHz.A collaboration of Universities involved since many years on the development of particle detectors for space will, design and build this instrument. The competence of the groups, the activity performed by this collaboration during the two previous PRIN devoted to the development of space instrumentation, the availability of laboratories equipped with advanced tools for detector qualification, would make possible the construction of this instrument at competitive cost and in a short time.