TARANIS:: A microsatellite project dedicated to the study of impulsive transfers of energy between the Earth atmosphere, the ionosphere, and the magnetosphere

TARANIS (Tool for the Analysis of RAdiations from lightNlngs and Sprites) is a microsatellite project of the CNES Myriade program, dedicated to the study of impulsive transfers of energy between the neutral atmosphere the ionospheric and magnetospheric plasmas. The science objectives include: (a) characterization of TLEs (Transient Luminous Events) and TGFs (Terrestrial Gamma-ray Flashes) including their global mapping, occurrence rates and the correspondence between both phenomena in order to determine the source mechanisms, (b) determination of triggering factors and formation conditions, (c) characterization of the parent lightning that causes TLEs and TGFs, (d) investigation of wave-particle interactions leading to precipitated (LEP) and accelerated (runaway) electrons, (e) effects on the radiation belts of low altitude sources by tracking of their variability from electron and wave measurements, (f) effects on thermospheric parameters (ionisation rate, NO,, 03, dynamics of the atmosphere) by on board measurements coordinated with ground-based observations. The project is multidisciplinary and uses complementary instrumentation including: micro cameras and photometers, X and gamma detectors, high energetic electrons spectrometers, electric and magnetic sensors. (c) 2007 Published by Elsevier Ltd on behalf of COSPAR.