Preparing EnVision: SO₂ measurements below and above Venus' clouds

Abstract : One of the primary objectives of the preselected En-Vision M5 proposal is the monitoring of volcanogenicspecies in Venus’ atmosphere, one of the most promi-nent being sulphur dioxide (SO2). Monitoring SO2below the clouds can be performed on the night-side near2.4μm, and is one science objective of theVenSpec-H channel (P.I.: A. C. Vandaele, BIRA) on-board EnVision. Monitoring SO2above the cloudscan be performed on the dayside in the200-300 nmrange, and is the main science objective of theVenSpec-U channel (P.I.: E. Marcq, LATMOS). Herewe present the analysis of two analogous datasets,namely IRTF/iSHELL ground based observations onthe nightside of Venus, and the most recent reanalay-sis of the Venus Express/SPICAV-UV dataset on thedayside of Venus