The WISDOM radar on the ExoMars rover designed to provide 3D mapping of the shallow subsurface at Oxia Planum

Abstract : The WISDOM radar on-board the Rosalind Franklin ExoMars rover has been specifically designed to characterize the shallow Martian sub-surface. It will be operated at Oxia Planum (the mission’s landing site) along the rover path and will reveal the sub-surface structure over a few-meter depth with a vertical resolution of a few centimeters. In combination with other instruments on-board the rover (especially, PanCam, Ma_MISS) , WISDOM will provide information essential to understand the 3D geological context and geologic evolution of the landing site, and to choose the best area and depth to collect samples. The instrument's Flight Model has been integrated in 2019 on the mission’s rover and a series of tests have been performed to characterize the instrument’s response and performance after integration. The data acquired during these tests will be used to obtain calibrated data from the measurements performed on Mars and retrieve quantitative information about the detected units (such as permittivity and spatial extension). Codes that take into account the specificities of the radar (accommodation above the surface, polarimetric capacity, antennas’ pattern…) have been developed to provide 3D visualization of the detected structures with an enhanced resolution. They are integrated in the automatic data processing pipe-line. Reflectors on the surface and off-track reflectors will be identified to avoid misinterpretation of the radargrams. Results obtained in artificial well documented environments and in natural analog environments will be presented to illustrate the capacity of the instrument to characterize in 2D and 3D the Martain shallow sub-surface.