The PLAnetary Transits and Oscillations of stars (PLATO) mission is set to launch in early 2027. Its primary objective is to identify and study numerous extrasolar planetary systems, with a particular focus on terrestrial planets located within the habitable zones of solar-like stars.
PLATO is also designed to investigate seismic activity in stars, which will allow for the precise characterisation of stars that host planets, including their ages. The mission's instrument concept incorporates 24 'normal' cameras and two 'fast' cameras. These will conduct ultra-precise, uninterrupted photometric observations of hundreds of thousands of stars over several years, seeking tiny dips in light that could indicate transiting exoplanets.
The mission is planned for a 4.5-year nominal duration. PLATO aims to provide accurate determinations of planetary radii and stellar properties, alongside estimates of stellar irradiation experienced by planets. Combined with ground-based observations, it will also offer accurate planetary masses and mean densities, enabling the exploration of planetary system architectures and their evolution.
The UK plays a significant role in the PLATO mission. Professor Don Pollacco of the University of Warwick leads the PLATO Science Management team and the exoplanet science programme. UCL's Mullard Space Science Laboratory led the design and build of the electronics for the 'normal' cameras, and Teledyne e2v in Chelmsford is manufacturing the CCD detectors.