First, water ice (frozen water) is abundant on Saturn’s moon Enceladus because it formed far from the Sun. Almost all the satellites of the giant planets (with the important exception of Jupiter’s Io), dwarf planets like Pluto, comets, and Kuiper Belt objects formed with a healthy endowment of water ice. Hydrogen is the most abundant element in the universe and oxygen is the third, so that translates into copious H2
O. Beyond a certain distance from the Sun (called the “frost line” or “snow line”), any water should be in solid form, and when the planets and satellites developed, ice was an important chemical component.
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