Early Dynamical Instabilities in Extrasolar Planetary Systems

A team from the California Institute of Technology will build a full picture for the formation and early evolution of the most commonly occurring planets found around nearby stars. Over the past two decades, surveys have shown that planet formation is efficient across the Galaxy. The most common mode of planet formation appears to generate planets a few times larger than Earth, with orbital periods smaller than one year.

Scientists have further shown that systems of planets outside our Solar System exhibit a uniform pattern in their orbits and masses. The project will build a model for the formation and early evolution of these planets. The program will involve public engagement, training of graduate students, and collaborations with teachers and students from local high schools.

The proposed research program will quantify the dynamical instability-driven early evolution of Super-Earths, with an eye towards identifying scattering mechanisms, modeling physical consequences, and compiling the associated observational predictions. First and foremost, the execution of this work will answer the fundamental question of how orbital instabilities among sub-Jovian planets are activated in the proportion needed to explain their period ratio distribution.

Second, the investigators will determine whether or not instability-driven sculpting can satisfy existing observational constraints. The investigators will determine how tidal dissipation and interactions of planets with leftover debris shape the current architectures of sub-Jovian extrasolar planetary systems.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.