# # Program information file # PROGRAM_ID 2021B057 PROGRAM_TITLE The progression of Saturn's seasonal atmosphere since Cassini PROGRAM_INV1 James Blake PROGRAM_INV2 Leigh Fletcher PROGRAM_INV3 Thomas Greathouse PROGRAM_INV4 Glenn Orton PROGRAM_INV5 James Sinclair PROGRAM_SCICAT solar system PROGRAM_ABSTRACT_BEG We propose high spectral resolution observations of Saturn's northern summer hemisphere using the TEXES instrument at the IRTF. These will be used to track the continued seasonal evolution of Saturn's atmospheric temperatures, winds and circulation two years after the end of the Cassini mission. We will examine the 2D [meridional and vertical] temperature and wind structure associated with the continued development and growth of the seasonal north polar vortex; the propagation of the equatorial stratospheric oscillation [QPO]; the amplitude and latitudes of thermal wave activity. October 2021 will be over half a Saturn year since Cassini's arrival in 2004, meaning that the proposed TEXES observations can be directly compared to conditions encountered during the same seasonal phase in the southern hemisphere to understand the asymmetries in the atmospheric response to seasonal dynamics and chemistry between the two poles. Comparisons with infrared imaging from Gezari et al. [1989] will provide constraints on interannual variability. PROGRAM_ABSTRACT_END