A recent article by Brian Koberlein in Forbes Magazine, on “The Wonder of Exoplanet Skies”, features WASP. The article is based on a recent paper by Jake Turner et al which includes observations of 15 hot Jupiters, of which seven are WASP planets.

The paper is one of the first to compile exoplanet transits in the near-UV “U” band. By comparing transit depths at different wavelengths one can discern facts about the exoplanet’s sky, such as whether is it clear or cloudy.

The most interesting result is apparently anomalous U-band transit depths in WASP-1b and WASP-36b, which appear shallower than in the optical, a finding that is hard to explain. Most likely this will have been caused by some observational bias, especially since there appears to be “red noise” in some of the transit profiles.

The image shows transits in the red (Harris R) and the near-UV (Bessell U), along with the residuals against a fitted model.

This sort of work is hard to do from the ground, but such studies point to a bright future for parameterising exoplanet atmospheres.