The North Polar region of Saturn, photographed by Voyager 2, 1981

The North Polar region of Saturn, photographed by Voyager 2, 1981. This picture shows isolated convective cloud features which are characteristic of the polar regions of Saturn's atmosphere. Saturn is a gas giant with an atmosphere consisting mainly of hydrogen and helium, similar to that of Jupiter. The atmosphere contains banded cloud structures similar to those seen on Jupiter, although Saturn's bands are wider nearer the equator and are fainter than Jupiter's. Detail of the cloud tops on Saturn is not visible from Earth, and it was not until the Voyager missions that circulation patterns in the upper atmosphere could be observed. NASA's two Voyager spacecraft were launched in 1977 to explore the planets in the outer solar system. Voyager 2 passed Saturn in August 1981, before continuing on to Uranus and Neptune. ©SSPL/NASA