Accelerated Orbital Decay of Hot Jupiter WASP-12b Linked to Star's Magnetic Field

WASP-12b, a hot Jupiter exoplanet, is spiraling into its star at an alarming rate, expected to collide in 3 million years. Scientists suggest the star's magnetic fields are causing the rapid orbital decay, dissipating tidal waves generated by the planet.

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Accelerated Orbital Decay of Hot Jupiter WASP-12b Linked to Star's Magnetic Field

Accelerated Orbital Decay of Hot Jupiter WASP-12b Linked to Star's Magnetic Field

WASP-12b, a hot Jupiter exoplanet, is spiraling into its yellow dwarf star at an alarming rate, with an expected collision in just 3 million years. This accelerated orbital decay has puzzled scientists, as it cannot be fully explained by the conventional theory of gravitational tidal waves.

Why this matters: Understanding the mechanisms driving the orbital decay of hot Jupiters like WASP-12b can provide valuable insights into the formation and evolution of planetary systems, ultimately shedding light on the possibility of life beyond Earth. Furthermore, this research could have implications for the study of exoplanet atmospheres and the potential for detecting biosignatures.

Led by Craig Duguid, the team suggests that the magnetic fields inside some stars can dissipate tidal waves generated by orbiting hot Jupiters. In the case of WASP-12b, inwardly propagating internal gravity waves (IGWs) from the planet interact with the star's magnetic interior, transforming into magnetic waves that eventually dissipate. This process causes a significant energy drain, leading to the hot Jupiter's rapid orbital decay.

WASP-12b is a unique hot Jupiter due to its extremely close proximity to its star, with an orbital period of just over one Earth day and a surface temperature of around 2,200°C. The planet orbits its yellow dwarf star at a distance of about 3.5 million kilometers in atriple-star system. "Our main result is that this previously unexplored source of efficient tidal dissipation can operate in stars within this mass range for significant fractions of their lifetimes,"stated Craig Duguid and colleagues.

The study suggests that this magnetic field mechanism could be at play in other hot Jupiter systems, particularly those orbiting F-type stars with convective cores. Further research into similar star-hot Jupiter systems could confirm this theory and provide valuable insights into the orbital evolution of these fascinating exoplanets.

The accelerated orbital decay of WASP-12b highlights the complex interactions between hot Jupiters and their host stars. With a surface temperature of approximately 2,200°C and an orbital period of just over one Earth day, this exoplanet is expected to collide with its star in about 3 million years. As scientists continue to study this unique system, the role of magnetic fields in the dissipation of tidal waves could shed new light on the fate of hot Jupiters across the universe.