Aqueous alteration is a geological process in which minerals are chemically altered by the presence of water. This alteration can occur through a variety of processes, including hydration, dissolution, precipitation, and ion exchange. Aqueous alteration is commonly observed in rocks and minerals exposed to water, such as in hydrothermal systems, weathering processes, and in the formation of clays and other secondary minerals. The study of aqueous alteration is important in understanding the history and evolution of planets, moons, asteroids, and other celestial bodies, as it can provide insights into the past presence of liquid water and potential habitability.