2518794

Target RA (J2000): 317.551544 and deg Target Dec (J2000): 10.73887 and deg Gaia GMag: 8.242 Programme ID: CH_PR240011 PI of observing programme: Hooton Title of programme: Treating exoplanets as planets: a deep dive into the reflective properties of an ultra-hot Jupiter Abstract: Designing observations to bridge the gap between our wealth of knowledge about solar system bodies with our relative dearth of knowledge about the composition of exoplanets is one of the biggest challenges of our age. Most studies of the reflected properties of transiting exoplanets have been limited to measurements of geometric albedo an important but incomplete part of the global picture. We propose to supplement previous TESS and Spitzer full-phase curves of MASCARA-1b by acquiring two CHEOPS full-phase curves. Ultra-hot Jupiters like MASCARA-1b are expected to radiate like blackbodies simplifying the separation of thermal and reflected signals in the phase curve. This will allow us to measure the phase integral geometric albedo spherical albedo and Bond albedo separately for three bandpasses across the optical and infrared. As knowledge of these parameters can be used to discriminate between the dominant scattering mechanism during the orbit this will constitute one of the most in-depth studies of the reflective properties of a transiting exoplanet to date. Additionally the transit will be used to search for evidence of nodal precession in the orbit of MASCARA-1b which if detected will yield information about tidal interactions between the planet and star. [truncated! Please see actual data for full text]