Amalia Karalis

Amalia’s research focuses on planet formation. Particularly, she is working on understanding the formation of a recently detected population of Jupiter sized planets around young stars from Kepler and TESS (Transiting Exoplanet Survey Satellite). Hot Jupiters are Jupiter-sized planets that are found very close to their host star. There are three proposed formation mechanisms for these gas giants: in situ formation, where the Jupiter forms at short orbital distances, disk gas migration, where torques from the disk gas cause the Jupiter to migrate to shorter orbital distances, and high eccentricity migration, where a perturber excites the Jupiter into a highly eccentric orbit and the subsequent circularization of the orbit decreases its orbital distance. The first two can occur when the star is still young, while the last process takes much longer. The detection of these young, puffy planets could indicate the existence of young hot Jupiters. However, these planets could also be smaller planets whose atmosphere have not yet cooled and settled onto their cores, making them appear very large.

Amalia’s work aims to understand the characteristics of these young planets. Particularly, she will determine the masses of these planets, which will indicate whether they are in fact hot Jupiters, formed or migrated at early times, or Neptune mass planets whose atmospheres have not yet settled onto their cores, thereby appearing puffy. This will provide a better understanding of the formation mechanisms of hot Jupiters, hinting at the dominant process for their formation.