Just like on Earth, water on other planets, satellites, and even comets comes in a variety of forms depending on multiple factors such as pressure and temperature. Aside from the gaseous, liquid, and solid states we are accustomed to, water can form a different type of crystalline solid called clathrate hydrate. Although they look similar to ice, clathrate hydrates have actually small water-based cages in which smaller molecules are trapped. These trapped “guest” molecules are essential for preserving the crystalline structure of clathrate hydrates, which would otherwise “collapse” into regular ice or water.
Click here for original story, Testing the waters: Analyzing different solid states of water on other planets and moons
Source: Phys.org