An Ice in a Warm Sea

Variations in pressure and temperature give rise to different phases of ice, which have varying properties and molecular geometries. Currently, twenty-two crystalline phases have been observed, including ice Ih, Ic, ..., XXI. In modern history, phases have been discovered through scientific research with various techniques including pressurization, force application, nucleation agents, and others. On Earth, most ice is found in the hexagonal Ice Ih phase. Less common phases may be found in the atmosphere and underground due to more extreme pressures and temperatures. Some phases are manufactured for nano scale uses due to their properties. In space, amorphous ice is the most common form as confirmed by observation. Thus, it is theorized to be the most common phase in the universe. Various other phases could be found naturally in astronomical objects.