PI: Nuno C. Santos

The discovery in the late 20th century of a New Solar System and of a multitude of new planetary systems orbiting other suns raised the field of Planetary System research into a new level. The study of Planetary Systems is now one of the hottest domains in modern astrophysics and the motivation behind the development of major ground telescopes/instruments and space missions by the main international agencies (e.g. ESO, ESA, NASA).

The team in IA is presently recognized as an international player in this field. The strong built expertise is based on state-of-the-art research in the field of Planetary Systems science, and is focused on the following research lines:

• The characterization of Solar-System atmospheres: In this context the team focuses on the problem of understanding the atmospheric circulation and climate systems, both from the point of view of planetary evolution and using Venus and Jupiter as model atmospheres for Earth-like and gas giant exoplanets. These studies will allow to use the Solar System models as a proxy for the characterization of exoplanet atmospheres (see below).
• The detection of exoplanets: this line is supported by our participation in state-of-the-art projects and missions (ESO and ESA) having the goal of finding planets orbiting nearby stars. Particular focus is given to the low mass/radius planet domain. In this context, the study if the best data reduction and analysis methods is addressed (e.g. the effects of stellar noise). Statistical studies of the discovered population of planets are also allowing to better understand the formation and evolution of planetary systems.
• The characterization of exoplanetary systems, including their internal structure, atmospheres, and host stars: this line includes the study of exoplanet internal structure and atmospheres, as well as of host star properties. This latter is fundamental for the correct characterization of the orbiting planets (e.g. for the determination of precise planet masses and radii).

Of relevance in these lines is the unique multidisciplinary approach of the team, coupling planetary system research with stellar astrophysics.

The research mentioned above is supported by our leadership position in international consortia for the development of new key instruments and missions. On the Solar System side, these include ESA's Venus Express (already ongoing) and JUICE missions. On the exoplanet side, we are now deeply involved in the ESPRESSO (ESO), Spirou (CFHT), CHEOPS (ESA), and PLATO (ESA) projects and missions. We are also paving the way towards a strong participation in a consortium proposing to ESO the construction of instrumentation for the E-ELT (HIRES).