# # Program information file # PROGRAM_ID 2024A983 PROGRAM_TITLE Comet C/2023 A3 PROGRAM_INV1 Ron Vervack PROGRAM_INV2 PROGRAM_INV3 PROGRAM_INV4 PROGRAM_INV5 PROGRAM_SCICAT comets PROGRAM_ABSTRACT_BEG The exceptional comet C/2023 A3 is shaping up to be perhaps the best comet of the last 30 years, and because of its small perihelion distance, it provides an unprecedented opportunity to study a bright comet over a large range of heliocentric distances. Furthermore, the comet has an unusually large geocentric Doppler shift over most of its apparition, which allows for a detailed study of species such as CH4 and CO with heliocentric distance. This is rarely the case, so early measurements of such species at larger Rh will be valuable in placing the species in context. These 2024A dates would allow us to study the comet pre-perihelion, which will significantly enhance the overall investigation that we plan in 2024B when the comet is mostly available post-perihelion. This additional coverage as a function of larger Rh will enable valuable comparisons to other comets studied with iSHELL and SpeX before water and other species are fully activated, PROGRAM_ABSTRACT_END