Architectures and Weather of Exoplanetary Systems

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The first direct images of planets around other stars have imparted a major new thrust to exoplanetary science. Not only have they offered unprecedented views into the structure of other planetary systems, but they have set the stage for the direct characterization of exoplanetary atmospheres. With extreme-contrast imaging technology arriving on large ground-based telescopes in 2014, and with the James Webb Space Telescope launching in 2018, the study of exoplanets is entering a new phase. My research is well-positioned to take advantage of these science-enabling developments. I have had a long-standing involvement in the study of exoplanetary systems and the characterization of brown dwarfs: giant planets' more massive kin. My current work targets the nearest systems with known circumstellar debris disks: belts of rocky and icy material analogous to that produced by asteroid and comet debris in the Solar System. I am also conducting the largest and most sensitive study of clouds and storms in brown dwarfs to study weather phenomena on extrasolar worlds. These are NASA-funded research projects that are being carried out by various members of my team at Stony Brook University: my former academic institution. My recent move into the position of Canada Research Chair in Extrasolar Planets at the University of Western Ontario has opened an opportunity to expand and unify these projects under a broader aim. The overarching goal of my research is to create a comprehensive context for the architecture and evolution of our Solar System, and to so address the question of how unique it is in being inhabited. The concrete themes that I propose to pursue build on my current projects. I plan: (1) to directly image extrasolar planets around nearby stars and to establish their frequency over a wide range of orbital separations that overlaps with the orbits probed by Doppler and transit-planet surveys; (2) to spatially resolve the dust-and-ice morphology of circumstellar debris disks in order to reveal the dynamical interactions of the disks with embedded planets; and (3) to study the cloud cover and weather phenomena in brown dwarf and exoplanetary atmospheres in a drive to understand their atmospheric dynamics and to ultimately establish the diversity of atmospheric phenomena in potentially habitable environments. The research takes full advantage of new extreme-contrast imaging capabilities being commissioned on ground-based telescopes: the Gemini Planet Imager on the 8 m Gemini South telescope and the PALM-3000 adaptive optics system on the 5 m Palomar Hale telescope. These will allow the routine imaging of extrasolar planets, the resolved mapping of circumstellar environments, and the precise monitoring of directly imaged planets to discern the minute flux variations cased by atmospheric storms. My team has the rare advantage of access to both of these facilities, ensuring faster progress and a broader scope—covering both the northern and the southern hemispheres—for our research program. Together with support that I am seeking through an Ontario Early Researcher Award, over the coming five years I will train two postdoctoral fellows, three PhD students, three MSc students, and ten undergraduates. In the course of the program these trainees will acquire advanced technical, computational, and analytical skills that are essential for research in exoplanetary astronomy, but that also open doors for professional realization in fields well outside of astronomy or academia.