B.S. (Physics), 1995, Massachusetts Institute of Technology Ph.D. (Astronomy), 2000, California Institute of Technology
Website: http://astro.berkeley.edu/~echiang
Theoretical astrophysics focusing on the origin and evolution of planetary systems, both Extra-Solar and Solar. I am particularly interested in long-standing puzzles for which there exist quality observational data but no adequate theoretical understanding. Current research areas in which I am keen to collaborate with graduate students, undergraduate students, and postdocs include:
(1) Extra-solar Planetary Dynamics. Extra-solar planets discovered by G. Marcy and his collaborators evince surprisingly small orbits, remarkably large eccentricities, and/or strongly resonant behavior due to mutual gravitational perturbations. I seek to understand the dynamical processes that sculpt these orbits.
(2) Planetary Rings. Rings furnish the most accessible laboratories for disk dynamics; they showcase a rich interplay of forces due to interparticle collisions, self-gravity, the gravity of shepherd moons, and electromagnetic fields. Striking architectures exhibited by the Neptunian arclets, the Saturnian spokes, and the Uranian ringlets remain unexplained.
(3) Protoplanetary Disks. Disks of gas and dust surrounding young stars provide the reservoirs from which planets ultimately coalesce. Spectra and images of these systems from ultraviolet to millimeter wavelengths are modelled to understand their thermodynamic states and accretion profiles.
(4) The Edgeworth-Kuiper Belt. Pluto has only recently been discovered to be one of at least tens of thousands of asteroid-sized bodies (Kuiper Belt Objects, or KBOs) orbiting the outer Solar System. This ring contains the most pristine, unprocessed material in our planetary system and holds clues to its early evolution. Active areas of research include an ongoing 3-year census of the many dynamical families of KBOs using telescopes at Kitt Peak and Cerro Tololo, and theoretical understanding of the Belt's origins.
