Image credit: Karen Teramura, IfA/UH

SUMMARY: Planetary systems consisting of a hot Jupiter orbiting its stars within 10 stellar radii open vast territories of new investigations. Much effort has been invested in recent years, both observationally and theoretically, to understand the interacting processes taking place in such systems. Several independent studies have converged on the same scenario: that a short-period planet can induce activity on the photosphere and upper atmosphere of its host star. The growing body of evidence for star-planet interactions includes a diverse array of photometric, spectroscopic and spectropolarimetric studies. The nature of SPI is modeled to be strongly affected by both the stellar and planetary magnetic fields, possibly influencing the magnetic activity of both bodies, as well as by irradiation and non-thermal and dynamical processes, even when the planet is mature and has stopped migrating. SPI offers an indirect way to detect and, with the ongoing observations and theoretical developments, measure planetary magnetic fields, offering the unique opportunity to explore the interiors of planets, as well as set constraints on the rapid hydrodynamic escape of hot Jupiter atmospheres.

CONVENOR: Evgenya Shkolnik, IfA/UH