Astronomy Tea Talk
In the last decades, exoplanet surveys have revealed the presence of giant planets (Jupiter-sized or larger) orbiting at least 5 % of Sun-like stars, a percentage likely to increase in the near future as our detection methods improve their sensitivity around the snow line. Due to their mass, giant planets have a significant impact on the dynamics of the entire planetary system, especially during their early dynamical evolution. In this talk, I will present how they shape the architecture of extrasolar systems, in particular the orbits of fellow giant planet companions, inner Earths or super Earths, and planetesimals. Giant planets can directly perturb their environment through secular interactions, scattering or resonances. Cold Jupiters can also initiate outside-in cascades of misalignments and eccentricities following close flybys of neighboring stars. I will discuss these complex dynamical mechanisms by comparing analytical expectations, N-body simulations, and actual observations, focusing especially on young benchmark systems that have been characterized with direct imaging.