Revealing Exoplanet Atmospheres With Ground-Based Transmission Spectroscopy

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

This award supports work to measure the chemical composition of ten transiting extrasolar planets (planets that appear to pass in front of their host star when observed from the Earth). The PI and his team will use the Gemini Observatory North and South telescopes to obtain optical spectra of the planets using the technique called transmission spectroscopy, which analyzes starlight after it passes through the transiting planet's atmosphere. To accomplish this, they will develop and use improved observational techniques of ground-based spectroscopy, make comparative studies of the planets, and test models of planetary systems formation and evolution. These observations will be incorporated into undergraduate and graduate laboratory classes taught by the PI. The PI will train and mentor a graduate student in technical and scientific skills. The data and analysis pipeline and atmospheric archive of the planets will be made publicly available through a web archive. This program consists of observing a subset of close-in gas giant exoplanets during transit. The observations are obtained using guaranteed time on the GMOS (Gemini Multi-Object-Spectrograph) instruments with low-resolution dispersive elements. The atmospheric survey will be carried out at optical (400 - 1000 nm) wavelengths and will simultaneously observe calibration and target objects. The data will be used to measure the abundances of water, methane, haze particles, and, potentially, a speculated optical absorber from transmission spectra.