A recent study led by the University of Geneva has revealed the existence of a remarkable multi-planetary system known as WASP-132. This system includes a Hot Jupiter, an inner Super-Earth, and an outer giant planet, challenging prior theories regarding the formation and migration of such planets.
Hot Jupiters are gas giants that orbit very close to their stars, making their formation in these regions difficult due to insufficient gas and dust. Traditionally, it was believed that these planets were isolated, having either ejected or consumed any neighboring celestial bodies during their migration towards their stars.
The WASP-132 system, however, presents a different scenario. The Hot Jupiter in this system completes an orbit in just over seven days, while the Super-Earth orbits in approximately 24 hours. A third planet, a massive giant, takes about five years to orbit the star. This configuration suggests a more stable migration process for the Hot Jupiter, preserving the orbits of its companions.
The findings, published in Astronomy & Astrophysics, stem from extensive observations that began in 2006 under the Wide-Angle Search for Planets program. Over the years, various instruments have confirmed the existence and characteristics of these planets, including the TESS space telescope and the HARPS spectrograph.
François Bouchy, an associate professor at UNIGE, emphasized the significance of this discovery, stating that it provides a new perspective on the dynamics of multi-planetary systems. The presence of both an inner Super-Earth and an outer giant planet alongside a Hot Jupiter calls into question established models of planetary migration.
Further observations are anticipated as the European Space Agency's Gaia satellite continues to monitor the system, potentially uncovering additional planetary companions.