ESA Science & Technology - Comparative Planetology: Transiting Exoplanet Science with JWST

Publication date: 15 November 2009

Authors: Clampin, M., et al.

Journal: JWST White Paper

The study of transiting exoplanets has provided most of the key data to date on the properties of exoplanets, such as direct estimates of their mass and radius (e.g.Charbonneau 2007), and spectral diagnostics of their atmospheres (e.g. Swain et al. 2008). The Hubble Space Telescope (HST) and Spitzer Space Telescope (SST) have both played lead roles in making the demanding, high S/N observations of light curves, and spectra of transiting exoplanets. Ground-based surveys have so far provided the candidate targets for space-based characterization studies. The study of transiting exoplanets requires the extraction of a differential signal from high S/N observations so the James Webb Space Telescope (JWST), by virtue of its 25 m² collecting area (~50x SST), will open up a new discovery space for transiting exoplanet science. Specifically, it will enable the characterization of intermediate and low mass exoplanets. The goal of this white paper is to provide an informational briefing for the panel on the expected capabilities of JWST for observations of exoplanet transits, in particular the characterization of transiting lower mass planets (d M_Nep).