2274600

Target RA (J2000): 66.370903 and deg Target Dec (J2000): -30.60043 and deg Gaia GMag: 9.978 Programme ID: CH_PR230018 PI of observing programme: Patel 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. [truncated! Please see actual data for full text]