Abstract

Close-in planets, characterised by short orbits around their host stars, demonstrate the complexities behind planetary formation, migration, and atmospheric dynamics. This work embraces a multi-faceted approach towards hot exoplanet atmospheres, commencing with the atmospheric characterisation of an ultra-hot Jupiter using archival data obtained from 1.5 m ground-based telescope. We recover strong detections of Fe I, FII , and Mg I while also modelling a peculiar H-alpha transit. Subsequently we prepare for atmosphere analysis via the detection two new sub-Neptunes around an adolescent K-star using photometry from TESS and CHEOPS . Our analysis evaluates that inner planet resides in the sparsely populated radius gap, indicating that it could be undergoing significant atmospheric evaporation. Lastly, I share UniSQ’s contribution towards preliminary target preparation for the upcoming Twinkle Space Mission, which will characterise exoplanet atmospheres over the course of its mission. This presentation also highlights some outreach endeavours I have contributed towards prior and in addition to this research, which primarily aim to increase astronomy accessibility and improve diversity in STEM .