EnVision: Mission to Venus

EnVision is the first mission to Venus that will explore the planet from its core to its upper atmosphere. EnVision will focus in particular on the interactions between the interior and the atmosphere.
 

The aim of EnVision will be to take a holistic look at our sister planet Venus and study its geological evolution, activity, and climate. The mission will address a number of key questions: 1) How did the surface and interior of Venus evolve? 2) How geologically active is Venus today and how active was it in its geological past? 3) How are Venus' atmosphere and climate influenced by geological processes? 4) Were there once water oceans on Venus and could ancient traces still be found on the surface? 5) How does Venus lose its heat, and when and why did the greenhouse effect begin on the planet?

The EnVision mission will build on the successes of previous missions to Venus, such as the Venus Express mission, which was operated by ESA from 2005 to 2014. EnVision is intended to work in synergy with the two NASA missions VERITAS and DAVINCI, which are also planned but currently subject to pending decisions regarding funding, thus enabling the most comprehensive investigation of Venus to date. The EnVision spacecraft will be a cubic, three-axis stabilized satellite weighing approximately 2.5 tons at launch and measuring approximately 2 x 2 x 3 m, including two deployable solar arrays. EnVision's scientific payload will consist of a radar that will also function as a microwave radiometer and altimeter and will map the surface of Venus. Three optical spectrometers (the VenSpec Suite:  VenSpec-M, VenSpec-U, and VenSpec-H) will observe the surface and atmosphere of Venus, and the Sub-Surface Radar Sounder (SRS), a high-frequency (HF) sounding radar, will explore the top kilometer of the subsurface. These instruments will be complemented by a radio tracking system that will map the planet's gravitational field to investigate its internal structure.

EnVision is scheduled to launch in the early 2030s from ESA's spaceport in Kourou, French Guiana, aboard an Ariane 64 rocket. EnVision will reach Venus after a 15-month journey. Upon arrival, the probe will fly through the upper atmosphere of Venus for another 15 months to slow down and gradually enter a scientific orbit. This low, quasi-polar orbit around Venus will have a variable altitude between 220 and 540 km, with an orbital period of approximately 94 minutes. The nominal total scientific duration of the mission is expected to be four years.