Exoplanet Missions

The European Space Agency's Ariel is the first mission dedicated to surveying the atmospheres of a large, diverse sample of known exoplanets — around a thousand — chiefly by transmission and emission spectroscopy at infrared wavelengths. Selected as ESA's fourth medium-class mission and planned for launch in 2029, it aims to link atmospheric composition to how and where planets form.

PLATO is a European Space Agency mission that will hunt for terrestrial planets in the habitable zones of bright, Sun-like stars using an array of small telescopes to watch for transits, while asteroseismology of the host stars pins down their ages and sizes. Selected as ESA's third medium-class mission, it is planned for launch in 2026.