Trappist (TRAnsiting Planets and PlanetesImals Small Telescope) will study exoplanets by measuring at high precision the "brightness dips" that can be caused by objects transiting (passing in front of) their parent star.
On Wednesday, researchers using NASA's Hubble Space Telescope announced the detection of P5, a tiny moon measuring just 6 to 15 miles (10 to 24 kilometers) across.