Title of programme: Constraining the morning and evening limbs of the hot jupiters WASP-79b and WASP-101b
Abstract: Observations of an exoplanet during a transit event has provided vast information regarding its bulk and atmospheric properties with photometric and spectroscopic observations. The usual assumption made while analysing thus observed lightcurves is that the thin terminator region around the disk of an exoplanet, the part seen in these kinds of observations, is uniform throughout the planetary disk. However, the most recent theoretical developments using 3D general circulation models of the planetary atmospheres have shown that, especially in the case of planets with high equilibrium temperatures, the approximation of uniform terminator is not good enough. These planets have a temperature gradient across the terminator that can produce chemical and aerosol inhomogeneities in this area. This non-uniform terminator will, in turn, produce asymmetric lightcurves, in both photometry and spectroscopy. This program aims to detect the direct evidence of this effect in exoplanet atmospheres using ultra-high precision photometry from CHEOPS. The effect of these asymmetries on the transit lightcurve can be as large as 1000 ppm for the most suitable targets, which CHEOPS should detect comfortably. To this end, based upon previous observations made with HST, WASP-79b and WASP-101b would be the most suitable targets to explore this effect with CHEOPS. Constraints from CHEOPS observations on aerosol properties would be very crucial in spectroscopic analysis of them with future observations.
Temporal Coverage
2023-01-20T17:17:00Z / 2023-01-21T05:48:00Z
Version
3.0
Mission Description
CHEOPS (Benz et al., https://doi.org/10.1007/s10686-020-09679-4) is a European Space Agency (ESA) mission in partnership with Switzerland with important contributions to the payload and the ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden and the United Kingdom.
The satellite has a single payload comprising an ultra-high precision photometer covering the 330 - 1100 nm wavelength range in a single photometric band. Observations are made as part of the Guaranteed Time Observing Programme that is formulated by the CHEOPS Science Team, and the Guest Observers Programme through which the Community at large can apply for CHEOPS time.