To develop neutral atmospheres engineering models in Europe for future missions at Venus and the Ice Giants, useful to the design of mission phases involving e.g. aerobraking, atmospheric entry, descent and landing.

Uncertainties on atmospheric densities and temperatures are major risk drivers for atmospheric entry and orbital maneuvers such as aerobraking or aerocapture. The EnVision mission scenario foresees orbit perigee lowering down to about 140km using aerobraking. Europe has gained a good expertise during the Venus Express mission, however there is no easily accessible model not to say engineering model to rely on for mission design at Venus. In comparison the Venus - GRAM model is developed and maintained by NASA MSFC.This study will target the development of an engineering model from at least the cloud top at 70km to the exosphere at Venus based on the combination of existing Global Circulation Model(s) and exospheric models developed in Europe. This shall be validated using Venus Express data (in particular densities and temperatures where available) during aerobraking.