An educational series of publications to learn more about about the objects in the night sky and the objects you may have viewed at our star parties.
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LEARN MORE ABOUT
Saturn from Cassini
Saturn, the sixth planet from the Sun is the second largest planet in our solar system. Saturn's intricate ring structure has been a point of fascination for astronomers for many centuries. It was in 1610 when Galileo turned his telescope on this giant planet and was the first person to see Saturn's beautiful ring system.
In 2004, NASA’s hugely successful Cassini Mission reached Saturn and returned amazing pictures and a wealth of new data and information about this fascinating planet.
Saturn has at least 30 known moons. Titan, largest of them, has an atmosphere and is easily visible through a telescope. . In January 2005, the Huygens probe landed on Titan and returned the first pictures from a moon other then our own.
Saturn's Ring System
The Saturn Ring System
The ring system is very complex and is made up of many, separate rings, including one that appears to be "braided". The rings are 274,000 km wide--twice as wide as the planet Jupiter and are composed mainly of ice and rocky material. For all their apparent size, they are less then a 100 feet thick and appear to vanish when seen edge-on from Earth.
Saturn will appear to become brighter over the next several years (2009-2017) in part because of the changing tilt the rings. Saturn is tilted 27 deg. with respect to its own orbit, so the rings appear to wobble as the planet goes around the Sun. As the angle of the tilt increases, the rings will begin to occupy a much larger visable surface area than the disk of the planet itself as seen from Earth.
Since Saturn's rings reflect sunlight so well, the brightness of the planet will appear to increase as a greater area of the rings becomes visable from Earth. This will continue right through 2017 when the process will then reverse.
Twice during Saturn's twenty-nine-year-long orbit the rings appear edge-on from Earth causing Saturn to appear unusually dim. The rings were edge on in 2010 and will be fully tilted in 2017 at which point the planet will appear more then twice as bright as in 2010.
Did you know?
Saturn is so light that it would float!
In spite of its giant size Saturn doesn't weigh very much. Composed mainly of hydrogen and helium, as a whole, Saturn is lighter than water and would float! Saturn's day is only a little more than ten hours long, which means that it rotates very quickly. The combination of its high rotation speed and low density makes the planet flatten out or "oblate" at its equator, an interesting phenomenon which can be clearly seen through a telescope.