WASP-132
WASP-132 is a star located about away in the constellation of Lupus. It is known to be orbited by two exoplanets and one more awaiting confirmation. With an apparent magnitude of 11.938, it is far too faint to be visible by the naked eye from Earth, but can be observed using a 60-mm aperture telescope as an orangish star.
Stellar characteristics
WASP-132 is a K-type main-sequence star with a spectral type of K4V, corresponding to its effective temperature of. It is about three-fourths as large as the Sun both in radius and mass, and radiates roughly a quarter of the luminosity of the Sun from its photosphere. The star is metal-rich with a metallicity of. Its age estimate varies wildly between publications from Gyr to Gyr. The same goes for its rotational velocity, with presented values of and.In 2017, a hot Jupiter exoplanet was discovered to orbit the star, followed by a hot super-Earth in 2022 and a cold super-Jupiter in 2024. This makes WASP-132 one of the only stars with planets both near a hot Jupiter and much farther out, alongside WASP-47.
Planetary system
WASP-132b
In 2017, the discovery of WASP-132b was announced alongside that of six other hot Jupiters. It was found through the analysis of transit photometry data obtained between May 2006 and June 2012 by WASP-South at the South African Astronomical Observatory, and was subsequently confirmed by radial velocity observations by the Swiss 1.2-metre Leonhard Euler Telescope's CORALIE spectrograph and transit photometry observations at TRAPPIST.The planet is relatively small for a hot Jupiter, having a mass less than half of Jupiter's and a radius 10% smaller. Due to the host star's dimness, it was the second least irradiated hot Jupiter discovered by WASP at the time of discovery, with an equilibrium temperature of ; only WASP-59b was colder at .
WASP-132c
From TESS observations conducted in 2019, a new transit signal was found to occur every, which was confirmed to be caused by a planet with a radius 1.85 times that of Earth in 2022. Archived radial velocity data from CORALIE and subsequent observations with HARPS indicate that the mass of the planet is approximately, corresponding to a bulk density of, consistent with an Earth-like composition.The existence of this planet implies that the nearby WASP-132b is improbable to have formed via high-eccentricity migration, the way most hot-Jupiters form. This scenario involves a giant planet that formed beyond the ice line falling into an eccentric orbit due to gravitational perturbations, which takes the planet closer to the star. Over time, the orbit circularizes much closer in than the original orbit. This is deemed unlikely to have happened to WASP-132b, since the migration would leave other nearby planets scattered or even ejected from the system as the eccentric Jupiter sweeps the vicinity of its orbit clean with its gravitational influence.