Eating Planets for Breakfast, Lunch, and Dinner: Signatures of Planetary Engulfment at all Phases of Stellar Evolution
Abstract
Most, if not all, TESS target stars can be expected to reside in binaries, as these stars are more massive than the Sun. Gravitational perturbations from a companion can drive a planet closer to its host star, potentially plunging the planet all the way into the star. While it is challenging to observe a planet during its plunge, we have predicted that, prior to its demise, such a planet will appear as hot as a Hot Jupiter (Stephan et al. 2018). This new class of 'Temporary Hot Jupiters' has recently been confirmed by TESS observations (e.g., HD 202772A b). As the planet is eventually eaten, it can impart distinct signatures onto the star. We follow the engulfment of planets by their host stars during different stellar life phases and calculate the changes in stellar parameters, such as stellar spin or luminosity, caused by this process. Our predictions for the observable signatures of these engulfment events will enable future and current endeavors to find post-engulfment stars, thus, advancing our understanding of planetary system architectures and dynamical evolution.
- Publication:
-
AAS/Division for Extreme Solar Systems Abstracts
- Pub Date:
- August 2019
- Bibcode:
- 2019ESS.....431907S