Tag Archives: JWST

The atmospheres of WASP planets with JWST

The James Webb Space Telescope is expected to revolutionise the study of exoplanet atmospheres following its launch in 2018, and WASP planets will be among the prime targets. Paul Mollière et al have been simulating the data expected, and have produced this illustration of the atmospheric emission spectrum of WASP-18b.

Spectrum of exoplanet WASP-18b as observed with JWST

The different coloured curves result from different assumptions about WASP-18b’s atmosphere. The lines along the bottom illustrate the spectral coverage of the different JWST instruments. In contrast to existing data (Spitzer results are shown as black squares), the JWST data will have both the spectral resolution and signal-to-noise to differentiate clearly between different models.

Mollière et al have also simulated spectra for cooler planets, such as WASP-10b and WASP-32b.

WASP-10b and WASP-32b simulated atmospheres observed with James Webb Space Telescope.

The different models are for different abundances of carbon relative to oxygen (C/O), showing that JWST should be able to settle the issue of which exoplanets have enhanced abundances of carbon relative to the Solar System.

Such simulations show that the results from JWST should be spectacular, opening up whole new areas of enquiry.

Looking forward to WASP planets with JWST

The $6-billion James Webb Space Telescope “will likely revolutionize transiting exoplanet atmospheric science due to a combination of its capability for continuous, long duration observations and its larger collecting area, spectral coverage, and spectral resolution compared to existing space-based facilities”, write Kevin Stevenson et al in a new paper looking forward to Cycle 1 observations of exoplanets with JWST.

Of interest to us is at WASP that, of the “community targets” identified by Stevenson et al as the best targets for characterizing exoplanet atmospheres in Cycle 1, seven of the twelve are WASP planets, and in particular “the most favorable target is WASP-62b because of its large predicted signal size, relatively bright host star, and location in JWST’s continuous viewing zone”.

This independent assessment validates WASP’s program of finding exoplanets transiting relatively bright stars, where they make the best targets for ongoing detailed studies.

JWST is now not that far off, as Stevenson et al remind us with this timeline:

Timeline Of James Webb Space Telescope