The Atmospheric Remote-sensing Infrared Exoplanet Large-survey sensitivity and performance

The Ariel space mission is set to perform spectroscopic characterization of the atmospheres of a broad and diverse selection of hundreds of exoplanets. The target list is designed to span a wide array of planetary masses, densities, equilibrium temperatures, and host star types, in order to investigate the physical processes driving the diversity observed in the exoplanet population. Utilizing a 1-meter class telescope, Ariel will capture atmospheric signals manifested as subtle variations—typically under 100 ppm—superimposed on the light of bright host stars, through transit, eclipse, and phase curve spectroscopy. Its instrument suite includes three photometric and three spectroscopic channels with Nyquist-sampled focal planes, enabling simultaneous coverage of the 0.5–7.8 micron spectral range. This configuration enhances observational efficiency and helps mitigate systematics from both astrophysical and instrumental sources. This contribution provides an update of predicted mission performance and control of systematics, taking into account the most recent developments in mission design and ongoing progress in spacecraft development, which will be briefly reviewed.