PLATO (for Planetary Transits and Oscillations of Stars) is an European Space Agency spacecraft under construction aimed at detecting and observing extra-solar planets. The aim is to observe relatively bright stars (magnitudes 4-11), that will support informative follow-up studies such as radial velocity measurements. It will detect exoplanets through the transit method (and presumably also detect transits of known exoplanets discovered by other means), and will observe the systems to gather asteroseismology data. Both these tasks require precise photometry (which is assisted by locating the telescope in space) and short cadences. Its general design is covering a wide field using a number of small telescopes. Plans are to launch in 2026.
The name PLATO 2.0 was used for a 2014 proposed plan-update during PLATO's planning stage, which emphasized aiming for terrestrial planets in the habitable zone of Sun-like stars