Planetary evolution is the study of the changes that occur on planets over time, including their formation, development, and eventual demise. This field of research involves studying the geological, atmospheric, and biological processes that shape a planet's surface and interior, as well as how these processes change over time. By studying planetary evolution, scientists can gain insights into the history and potential future of planets, including Earth, as well as understand the conditions that are necessary for life to exist on other planets in our solar system and beyond.