Exoplanet Characterization

During the primary transit, we measure the transmission spectrum of the planet as light from the host star is absorbed by chemical species in the planet's atmosphere. These data are sensitive to the relative chemical abundances and the presence of cloud our haze particles. During the secondary eclipse, we measure the dayside emission spectrum of the planet as its light is blocked by the host star. Emission spectroscopy is sensitive to the absolute chemical abundances and the thermal profile. We observe the phase variation to map the planet's emission as a function of longitude. This probes the dynamics of energy transport in the planet's atmosphere.