Young Planets in Star Clusters
While thousands of exoplanets are known, most orbit anonymous stars in the Galaxy that are between one and ten billion years old. I have been using TESS, Gaia, and Kepler to find and study planets around stars in clusters younger than one billion years. The stellar ensembles in which these planets reside enable precise age measurements, which helps us put together a timeline for planet evolution.
Ages of Field Stars
While stars in clusters yield gold-standard ages for a select set of planets, age-dating methods applicable to field stars might let us study planet evolution for a much larger sample of planets. Rotation-based age dating is one of the most promising methods to age-date FGK stars on the main-sequence.
Complex Periodic Variables
The “complex periodic variables” are young low-mass stars that show highly structured and periodic optical light curves. They seem to be explained by clumps of circumstellar material that corotate with the star for hundreds of stellar rotation cycles. The origin and composition of this material is unknown. Resolving the issue will likely deepen our understanding of stellar physics, and clarify the circumstellar environments to which close-in exoplanets are subject early in their lives.
Dissolving Star Clusters
Stars form in clusters when molecular clouds collapse. After the gas from the birth cloud disperses, most of the stars escape the cluster’s gravitational pull and gradually populate the galactic disk. Using many of the same tools that I use to study exoplanets, I also study cluster dissolution. The near-term goals are to reconstruct the initial cluster configurations, and to understand the processes that dictate the shapes, sizes, and orientations of these loosely aggregated groups of stars. A long-term goal is to understand whether we might be able to identify and study stars in the Sun’s birth cluster.
Long-term Fates of Hot Jupiters
Tides are expected to cause hot Jupiters to inspiral into their stars and be torn apart, but it is not clear how long this takes. Beyond determining the lifespan of hot Jupiters, the answer also has implications for whether the Earth will be consumed by the Sun in the distant future.
Design and Analysis of Transit Surveys
I’m broadly interested in the design, execution, and analysis of planet-hunting surveys, particularly using the transit method.