Space, an Italian instrument will measure Mercury gravitational field
It will be an all-Italian instrument called ISA-Italian Spring Accelerometer that will detect stress and accelerations experienced by ESA’s satellite: it will measure Mercury gravitational field, describe the rotation state and test a few assumptions of the Theory of General Relativity.
ISA will head to Mercury onboard the European spacecraft MPO (Mercury Planetary Orbiter), one of the two spacecrafts of the BepiColombo mission and will measure the slightest accelerations of the spacecraft, remaining in operation for the duration of the cruise phase. Along with the “More” experiment, ISA will aim at increasing the performances of orbit determination in order to measure the gravitational field of Mercury.
Deputy principal investigator of the ISA instrument is Francesco Santoli from IAPS-INAF, who is in charge of system engineering for space applications, definition of space and ground-based experiments for fundamental physics, performance analysis of complex systems and mechanical ad thermal design of scientific instruments and related testing and calibration facilities.
“ISA is an instrument that measures the satellite accelerations caused by forces that push it from the outside – said Santoli – By putting together ISA’s measures and those of the orbit actually followed by the satellite, provided by the tracking system, it will be possible to calculate the gravitational field of Mercury very accurately. Moreover, the accelerometer will allow to correct the measures of the tracking system by keeping into account the internal dynamics of the satellite, caused by the movement of appendixes and fuel”.