The Voyagers’ Tale

 In this introductory chapter, we review the remarkable journey of Voyager 1 and Voyager 2 spacecraft as they ventured into the outer reaches of our Solar System, unravelling the mysteries of distant planets and their intricate satellite systems. Along their journey, they unveiled a series of astonishing revelations, particularly regarding the presence of subsurface oceans of water on certain moons, which have since been classified as “ocean worlds.” Furthermore, we delve into the phenomenon of tidal heating, a fascinating energy source that plays a pivotal role in shaping the geological landscapes of planetary bodies subjected to its influence. As such, this chapter serves as a starting point for the book as it lays out the different moons that will be visited in detail (Europa, Ganymede, Callisto, Enceladus, and Titan) in the subsequent chapters, as well as providing insight into some of the fundamentals in planetary science.