FINESSE (for Fast Infrared Exoplanet Spectroscopy Survey Explorer) was a planned space observatory to perform infrared spectrographic observations of 500 extra-solar planets. It was a NASA MIDEX (Medium-class Explorers Program) candidate proposal for a 2019 decision. A 2023 launch date was targeted with a mission of at least two years. It would reside at the Earth-Sun L2 Lagrangian point. In February 2019, NASA selected a competing proposal, SPHEREx. The FINESSE plan was considered redundant, given the ESA ARIEL plan.