Because Jupiter is the largest planet, during solar system formation it affected the orbits and composition of all the other objects. Jupiter is mostly hydrogen and helium and is like a cooled-down piece of the sun. Intermediate-weight elements like oxygen, carbon and nitrogen combined with hydrogen to form water, methane and ammonia, which make up the clouds of giant planets. Water is key because oxygen is the third most abundant element after hydrogen and helium. Thus, Earth’s oceans, the polar caps of Mars, and the icy moons of the outer system owe their existence to Jupiter. Water is also a major player in the meteorology. It brings energy up from below, and that energy combines with the energy of sunlight to power the winds. The wind patterns, made visible by clouds, make Jupiter a fluid dynamics laboratory worthy of study because the patterns are so different from those on Earth. Juno has instruments to observe all the properties of the giant planet, and it is the first spacecraft to observe the poles. Nevertheless, the blind men and the elephant is a valid analogy because Jupiter is such a rich object and has so many unanswered questions waiting to be answered.