Rocky Planets and Moons
Why did life evolve on Earth but not on any other known terrestrial planet? One of the necessary ingredients for planetary habitability is long-term climate stability, which on Earth is achieved through the interplay between its rocky layers and surface elements (oceans and atmosphere). There are other planetary bodies in our Solar System (such as Venus) that are compositionally similar to Earth, and yet they do not have plate tectonics, liquid oceans or complex life. Is Venus our older sister, or our evil twin? We can use physical models of rock deformation to understand the divergent evolutions of terrestrial planets. We can use observation from planetary missions (including Venus, Mars and the Moon) to compare geological features on Earth with those on other solid planetary bodies, in order to explain the similarities and differences between planetary surfaces and interiors. Such analysis provides an important link between space missions and geological expeditions on our own planet.