TAP Colloquium: Dynamical Chaos as a Tool for Characterizing Multi-planet Systems

Daniel Tamayo, University of Toronto
Monday, September 11, 2017 - 4:00pm
Kuiper Space Sciences Building, Room 312

Many of the multi-planet systems discovered around other stars are maximally packed. This
implies that simulations with masses or orbital parameters too far from the actual values will
destabilize on short timescales; thus, long-term dynamics allows one to constrain the orbital
architectures of many closely packed multi-planet systems. I will present a recent such application
in the TRAPPIST-1 system, with 7 Earth-sized planets in the longest resonant chain
discovered to date. A central challenge in such studies is the large computational cost of
N-body simulations, which preclude a full survey of the high-dimensional parameter space
of orbital architectures allowed by observations. I will discuss our recent successes in training
machine learning models capable of predicting orbital stability a million times faster than
N-body simulations, and the discovery space that this opens up for exoplanet characterization
and planet formation studies.