This area focuses primarily on the study of planets, planetary systems, and the processes that form them. Understanding the processes that changed the early Earth from a hot magma ocean phase to an Earth with atmosphere-ocean systems and plate tectonics similar to that we are familiar with today is essential for understanding planetary habitability. It is a strongly interdisciplinary field that draws on knowledge from a wide range of disciplines, such as planetary astronomy, geology, geochemistry, geophysics, atmosphere and ocean science, and the study of extrasolar planets.