Eric Agol

Title: New techniques for studying extrasolar planets

Abstract: I review several novel approaches to exoplanet detection and
characterization, including transit-timing variations (TTV), exoplanet mapping
using phase variations and eclipses, and transits of white dwarfs.
TTV may be used to characterize multi-planet systems by measuring
deviations from periodicity of a transiting planet due to the gravitational
pull of companion planets.  Many examples of systems with TTV have been
found by the Kepler satellite, with eight planet candidates confirmed by
this technique.  Infrared phase variations measured with Spitzer have been
used to characterize the climate of hot Jupiters and to make longitudinal
maps, constraining atmospheric circulation models.  I will
present the first eclipse map of a hot Jupiter based on Spitzer, which may
be a taste of what will be done with JWST.  Finally, I will look well into the
future towards studying Earth-like planets in their habitable zones.  Observations of
Earth with the EPOXI satellite show that phase variations may be used to
make longitudinal maps of habitable planets with continents and oceans,
even in the presence of variable cloud cover.  Such observations might be
carried with future large space-based occulting or coronagraphic telescopes.
I will conclude with a more speculative idea on the detection and characterization
of habitable planets around white dwarfs