The astrophysics of the PLATO space mission
Planetary bodies orbiting other stars have begun to be characterized physically, but the next stage of the discovery process, will require an increase in sensitivities and resolutions in order to provide for data that can be used for Comparative Planetology in the real sense of the term. This means being able to perform a direct comparison, both between objects outside the Solar System, as well as with objects within our home system. We also want to understand the relation between the planet and the host star during their joint evolution.
In this context, the recently selected ESA M3 mission PLATO is going to be a unique and necessary tool.
The objective of this mission is to determine the radii and masses of Earth-sized transiting exoplanets and located in the habitable zone of solar like stars. Since these parameters are determine, so far, in terms of the Stellar masses and radii, the uncertainty in in the values of the host star are transferred into planetary uncertainties which are magnified and can be ~ 50% in some cases. The PLATO mission will measure very accurately the light curve profile of planetary transits, and, simultaneously determine the masses and ages of the host star itself through the detection of the astroseismic p-modes, and through high performance ground based follow-up radial velocity observations thus measure the masses of the transiting planet with unprecedented precision.
When launched in 2024,PLATO will provide for well determined radii, masses and ages of exoplanets of all sizes down to that of the Earth. In this talk, the rationale behind the mission is outlined, while the scientific requirements of the mission itself, and including the technology and strategy, is described in some detail.