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Target RA (J2000): 140.656570 and deg Target Dec (J2000): 50.60373 and deg Gaia GMag: 8.82 Programme ID: CH_PR140062 Programme Manager: DELINE PI of observing programme: Benz Title of programme: Axis 2 - Constraining atmospheric properties of an eccentric gas giant (CAPEGG) Abstract: HD 80606 is a unique planetary system with a Sun-like star hosting a highly-eccentric (e > 0.9) Jupiter-size planet with an orbital period 111.4 days. The orientation of the system with respect to the Earth is such that we are able to see both the transit and the occultation of HD 80606 b. The occultation occurs a few hours only before the periastron passage allowing us to observe the planet dayside at its highest temperature. Laughlin et al. (2009) could determine that the atmospheric temperature undergoes a rapid heating of more than 500 K (from 725 K to 1250 K) when approaching the star. The planet spends most of its time far from its star where the received irradiation is hundreds of times smaller than the one at periastron allowing for reflective clouds to form in the atmosphere. The program aims at observing the occultations of HD 80606 b to constrain its reflectivity (geometric albedo) and infer the presence of reflective clouds their composition and/or possible on-going evaporation processes. [truncated! Please see actual data for full text]