remote sensing Technical Note Determination of Venus’ Interior Structure with EnVision Pascal Rosenblatt 1,*, Caroline Dumoulin 1 , Jean-Charles Marty 2 and Antonio Genova 3 1 Laboratoire de Planétologie et Géodynamique, UMR-CNRS6112, Université de Nantes, 44300 Nantes, France;
[email protected] 2 CNES, Space Geodesy Office, 31401 Toulouse, France;
[email protected] 3 Department of Mechanical and Aerospace Engineering, Sapienza University of Rome, 00184 Rome, Italy;
[email protected] * Correspondence:
[email protected] Abstract: The Venusian geological features are poorly gravity-resolved, and the state of the core is not well constrained, preventing an understanding of Venus’ cooling history. The EnVision candidate mission to the ESA’s Cosmic Vision Programme consists of a low-altitude orbiter to investigate geological and atmospheric processes. The gravity experiment aboard this mission aims to determine Venus’ geophysical parameters to fully characterize its internal structure. By analyzing the radio- tracking data that will be acquired through daily operations over six Venusian days (four Earth’s years), we will derive a highly accurate gravity field (spatial resolution better than ~170 km), allowing detection of lateral variations of the lithosphere and crust properties beneath most of the geological ◦ features. The expected 0.3% error on the Love number k2, 0.1 error on the tidal phase lag and 1.4% error on the moment of inertia are fundamental to constrain the core size and state as well as the mantle viscosity. Keywords: planetary interior structure; gravity field determination; deep space mission Citation: Rosenblatt, P.; Dumoulin, C.; Marty, J.-C.; Genova, A.