Exoplanets
Unusual Exoplanets
The success of wide-field time domain surveys has uncovered evidence for many exoplanet systems that differ dramatically from our own Solar System. Two particular types of systems that are studied in my group are (i) the relic exoplanet systems left over at the end of stellar evolution, once the parent star has become a dim white dwarf, and (ii) the unusual debris clouds first found in the light curve of “Boyajian’s Star.” In both types of systems, a mix of dynamical processes — from strong scatterings to Kozai-Lidov oscillations — are responsible for destabilizing the original orbits of exoplanets and associated minor bodies, and creating the unusual signatures seen by observers.
Tidal Evolution
Tidal forces couple the orbits of planets to their internal evolution. The “dynamical tide” leads to a particularly rich set of phenomenon, as it stochastically exchanges energy between the orbit and the internal oscillation modes of the planets and stars. By using asteroseismic observations, astronomers can find evidence for dynamically excited tidal oscillations directly, and the long-term evolution of the dynamical tide dictates the orbital evolution of many strongly interacting exoplanet-star systems.