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.
Highlights
Why Venus and Earth evolved so differently remains an open issue
The current solution of the Venus gravity field was determined from the radio tracking data of the NASA Magellan spacecraft [6,7] and the Pioneer Venus Orbiter (PVO) [8,9]
This recovered gravity field shows a non-uniform spatial resolution ranging from 540 to 170 km, preventing the full detection of the gravity signal induced by lithospheric loads, as well as crustal density and thickness variations
Summary
Why Venus and Earth evolved so differently remains an open issue. The geological history of Venus is the most unknown among the terrestrial planets, preventing a full understanding of the processes that led to its current state. The current solution of the Venus gravity field was determined from the radio tracking data of the NASA Magellan spacecraft [6,7] and the Pioneer Venus Orbiter (PVO) [8,9] (the Venus Express spacecraft was almost not tracked during the lowest altitude part of its orbit, not allowing improvement of the resolution of the Magellan/PVO solution [10,11]) This recovered gravity field shows a non-uniform spatial resolution ranging from 540 to 170 km, preventing the full detection of the gravity signal induced by lithospheric loads, as well as crustal density and thickness variations.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
