Electrical activity in Jupiter is so strong that it pours billions of watts into Earth's own magnetic field every day. This processed color image of Jupiter was produced in 1990 by the U.S. Geological Survey from a Voyager image captured in 1979. The colors have been enhanced to bring out detail. Zones if thought-colored, ascending clouds alternate with bands of dark, descending clouds. The clouds travel around the planet in alternating eastward and westward belts at speeds of up to 540 kilometers per hour.
Tremendous storms bug as earthly continents surge around the planet.
Some scientist theorize that beneath the atmosphere there is no solid mass at the center of Jupiter, but that the planet's unique temperature and pressure condition sustain a core whose density is more like liquid or slush. In March 1972, NASA launched the pioneer spacecraft to observe the asteroid belt and Jupiter. Arriving at Jupiter in December 1973, Pioneer 10 revealed Jupiter's intense radiation output, is tremendous magnetic field, and the probability of a liquid interior. One year later, Pioneer 11 flew by Jupiter on its way to Saturn, providing even more detailed imagery and measurements, including our first close-up look at the giant planets polar regions. Then, in August and September 1977, NASA launched the two Voyager spacecraft to the outer solar system.