# # Program information file # PROGRAM_ID 2023B020 PROGRAM_TITLE The thermal structure of Venus' mesosphere from high resolution observations of CO2 lines PROGRAM_INV1 Rohini Giles PROGRAM_INV2 Thomas Greathouse PROGRAM_INV3 Therese Encrenaz PROGRAM_INV4 Amanda Brecht PROGRAM_INV5 Kandis Lea Jessup PROGRAM_SCICAT major planets / satellites PROGRAM_ABSTRACT_BEG We propose TEXES observations to study the thermal structure of Venus' mesosphere. A comprehensive understanding of the thermal profile near the cloud tops is crucial in studying the planet's dynamics, including the extreme super-rotation that causes the cloud tops to rotate 60-80 times faster than the planetary body itself. We will use the TEXES instrument in MAP mode to make high-resolution measurements of CO2 absorption lines at 790-795 cm-1 across the entire planetary disk. These measurements will be inverted using the NEMESIS retrieval algorithm, in order to produce a three-dimensional map of the temperature profile at 58-85 km. This will be used to search for spatial variability, including large- and small-scale atmospheric waves. By repeating these measurements on short and medium timescales, and by comparing results with historic data, we will be able to study the temporal variability in the thermal structure. PROGRAM_ABSTRACT_END