WASP-132 is a unique multiplanet system in that both the inner rocky planet and the newly discovered outer giant planet are in a system that includes a hot Jupiter planet. This suggests that hot Jupiter migrated via a rare dynamically cooled mechanism and helps further our understanding of how hot Jupiter systems form and evolve. .
The WASP-132 system includes hot Jupiter (in the foreground), an inner super-Earth (passing in front of the orange host star), and the cold planet WASP-132d. Image credit: Thibaut Roger, University of Geneva.
A hot Jupiter is a planet with a mass similar to Jupiter, but it orbits closer to its star than Mercury, which orbits the Sun.
Because there is not enough gas or dust for these giant planets to form where they are observed, the established theory is that they originate far from their stars and are not planets. They move inward as the system evolves.
Until now, it was thought that hot Jupiter was orbiting the star alone, as other planets in the system were ejected as it moved toward the star.
Two extra planets in the WASP-132 planetary system now cast doubt on this theory.
“The WASP-132 system is an excellent laboratory for studying the formation and evolution of multiplanetary systems,” said Dr. François Bouchy, an astronomer at the Geneva Observatory.
“The discovery of hot Jupiters alongside inner super-Earths and distant giants challenges our understanding of the formation and evolution of these systems.”
“This is the first time I have observed such a configuration.”
Hot Jupiter WASP-132b orbits its parent star every 7.1 days. Super Earth WASP-132c orbits the star in just 24 hours and 17 minutes.
The newly discovered ice giant, named WASP-132d, will orbit its host star for five years.
Dr David Armstrong from the University of Warwick said: “Finding planets inside the hot interior of Jupiter is particularly rare, so the detection of an inner super-Earth was exciting.”
“We conducted an intensive campaign using state-of-the-art instruments to characterize its mass, density and composition, revealing a planet with a similar density to Earth.”
“The discovery of this planet adds further complexity to the WASP-132 system, as the movement of hot Jupiter towards the host star due to dynamic perturbations destabilizes the orbits of the other two planets.”
“This suggests a more stable, ‘cooler’ migration path for hot Jupiter in the protoplanetary disk that surrounds young stars and is the site of planet formation.”
Regarding this discovery, paper Published in today’s magazine astronomy and astrophysics.
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nolan greaves others. 2025. Discovery of a cold giant planet and measurement of the mass of a hot super-Earth in the multiplanetary system WASP-132. A&A 693, A144; doi: 10.1051/0004-6361/202348177
Source: www.sci.news
