ISA (Italian Spring Accelerometer): A new configuration for the Radio Science Experiment

We describe the accelerometer to be used in the Radio Science Experiment conceived for the BepiColombo space mission to Mercury. The key rôle of the ISA is outlined in order to remove from the list of unknowns the strong non-gravitational perturbations acting on the satellite. The main characteristics of the three-axis accelerometer are given, with particular emphasis on its configuration inside the planned spacecraft and to the attenuation of the thermal perturbing effects that represent one of the major difficulties in a gravimetry experiment.