To understand why to explore Venus, it is necessary to remember that it is similar in size and close to an orbital point of view of the Earth. The two planet necessarily absorbed the same materials in the protoplanetary disk, underwent a similar meteoric and cometary bombardment, so that they originally had a similar composition. However, there is currently only one model of evolution of an Earth-sized telluric planet, Earth. So according to this model, Venus should be as habitable as Earth, with a potentially slightly higher temperature, but not the current hell. What makes the exploration of Venus essential is that we do not know when and why these two planets diverged. We therefore need to know whether this point of divergence can still appear on Earth and make it uninhabitable.
The second driving force behind the exploration of Venus is the study of exoplanets, which has become one of the major disciplines of astronomy in the 21st century. One of the primary goals of studying planet outside the solar system is to find stars that can harbor life as we know it. Currently, the only information we have about exoplanets is their size, their distance to their star, their mass and the presence of an atmosphere. But with only this data we would not be able to differentiate the Earth from Venus if we came across a copy of our system. We need to understand what caused the differences between the two planets closest to the solar system to be able to make our evolutionary models more reliable and apply them to planets outside our system.
In order to better understand the objectives of the future exploration of Venus, we must first understand why it is so difficult and what we do not know. Next, the scientific objectives selected by the NASA think tank must be listed.