EUCLID : Dark Universe Probe and Microlensing planet Hunter

There is a remarkable synergy between requirements for dark energyprobes by cosmic shear measurements and planethunting by microlensing. Employing weak and strong gravitational lensingto trace and detect the distribution of matter on cosmic and galactic scales, but as well as to the very small scales of exoplanetsis a unique meeting point from cosmology to exoplanets. It will use gravity as the tool to explore the full range of masses not accessible by any other means. EUCLID is a 1.2 m telescope with optical and IR wide field imagers and slitless spectroscopy, proposed to ESA Cosmic Visionto probe for dark energy, baryonic acoustic oscillation, galaxy evolution, and an exoplanethunt via microlensing. A three-month microlensing program will already efficiently probe for planetsdown to the mass of Mars at the snow line, for free floating terrestrial or gaseous planetsand habitable super-Earth. A 12+ month survey would give a census on habitable Earth planetsaround solar like stars. This is the perfect complement to the statistics that will be provided by the KEPLERsatellite, and these missions combined will provide a full census of extrasolar planetsfrom hot, warm, habitable, frozen to free floating.