The Terrestrial Planets

For the structure of this chapter we chose to discuss the terrestrial planets and their satellites in terms of their geological evolution with time. We start with ancient times and end with modern times. Orthogonal to this time line, we describe the processes and their effects acting on each planetary body. Our home planet, Earth, serves as a reference framework and important anchor point for our comparative planetology studies because it is the best studied object for which we have knowledge gained from hundreds of years of sample analyses, mapping efforts, drilling, mining, and remote sensing, to name only a few sources of information. Comparing the entire suite of terrestrial planets requires to individually characterize each of them and the processes acting on them through time. However, there are several limitations involved in such a reconstruction, partially due to the discontinuous and fragmentary nature of the accessible geologic records and the lack of enough well-contextualised field data.