Two satellites of the Galileo constellation, accidentally placed on eccentric orbits, allow to test one of the pillars of Einstein’s theory of gravitation: the equivalence principle. After three years of measurements and data processing, a surprising result and a new world record: the test performed is 5 times better than the one performed 40 years ago by Gravity Probe A.

The aim of this new project is to study short range interactions using atom interferometry techniques. This experiment will allow realizing precise measurements of gravity at short distance, searching for possible deviations to Newtonian gravity. Such deviations are made possible by new gravitational-type interactions with range on the order of the micrometer, as considered by various unification theories. The measurement of such interactions appears as a promising way for the observation (...)

In the context of future space missions in fundamental physics (SAGAS, STE-QUEST, OSS, ….) a coherent laser link for clock comparisons, navigation, and data transmission will be essential. This is the long term aim of DOLL (Deep Space Optical Laser Link). In a terrestrial environment a satellite to ground coherent optical link (Mini-DOLL project) has applications for clock comparison, satellite orbit determination (optical Doppler ranging) and high bandwidth data transmission by phase (...)