Saturn-the Ringed Planet
Saturn, the sixth planet, is the last one visible to the naked eye. Its rings, visible only through a telescope, make it the most striking and beautiful sight in the Solar System (Fig). On seeing Saturn through his telescope, Galileo described the planet as having ears! These were actually three rings that girdle Saturn's equator. It is the second largest planet, exceeded in size and mass only by Jupiter. Saturais colder than Jupiter. The temperature at the top of its clouds is -180"~. Like Jupiter, Saturn consists mainly of hydrogen and helium, with traces of ammonia, methane and other compounds. Its average density is less than that of water. Thus, if we could put Saturn in a large enough ocean, it would float!
The rings of Saturn are its most distinctive feature, giving it a matchless grace. The rings are in fact a thousand tightly packed individual ringlets, like the grooves on a gramophone record. Even the supposed gaps in the rings have been found to contain small particles. Most astounding of all, a new outermost ring contains two strands twisted around each other like the threads of rope. The rings are made up of large chunks of solid matter-probably ice coated rocks.