Water, as ice, is one of the most widespread, intriguing and familiar compounds on the planet, in the solar system and beyond. On this planet it falls as snow, forms lacy deposits on winter windows, creates skating surfaces on lakes, gracefully drapes rock cliffs, packs thickly on the polar oceans and lays even thicker on the ice caps blanketing Greenland and Antarctica.
Beyond the planet Earth, Ice is present in the frozen oeans of Jupiter’s moon Europa, in the particles of Saturn’s rings and in the spectacular tails of passing comets. Beyond the Solar System, many light years beyond the Earth, ice is present in the dense molecular clouds of the regions where new stars form.
