Abstract :
The field of exoplanetary science has rapidly evolved over the past three decades, revealing an astonishing variety of planetary systems beyond our Solar System. The development of detection techniques such as transits, radial velocities, and direct imaging has allowed us to discover thousands of exoplanets, ranging from gas giants in extreme orbits to Earth-like worlds around ultra-cool stars.
In this seminar,I will explore some of the most peculiar exoplanetary systems discovered to date, highlighting the vast diversity of planetary architectures. In particular,I will focus on two recent discoveries in whichI have played a leading role. The first, *WASP-193b*, is an exceptionally low-density hot Jupiter, the lightest of its kind ever found and the second-least dense exoplanet across all known types. The second system, *TOI-2267*, consists of two ultra-cool dwarf stars, each hosting its ownplanetary system—planets b and c orbiting the primary star (TOI-2267 A) and planet d likely orbiting the secondary component (TOI-2267 B). Both systems, WASP-193 and TOI-2267, challenge current planetary formation models, as their properties are difficult to reconcile with the established understanding of how planets form and evolve.
These cases exemplify what we call 'the great diversity of exoplanets', a reminder that planetary formation and evolution can lead to configurations far beyond what was once thought possible.
