Have you ever seen the rings of Saturn through a telescope? They are one of the most astonishing things to see with your own eyes.
Saturn is a Jovian planet, and every Jovian planet has rings, along with many moons. Have you ever wondered what rings are and what causes them? Saturn’s rings are made of water ice particles that vary in size from small dust grains to the size of a boulder. Even though the rings look solid they are not solid. They consist of particles that orbit Saturn independently. The rings of Saturn may look very bright, but they are just reflecting the Sun’s light.
Planetary rings are created by the presence of multiple moons orbiting very close to the planet. There are two possible explanations for how rings are formed. One is that if a moon gets too close to Saturn it will experience extreme tidal forces and shatter or break apart. The other possibility is that a moon that is orbiting near the planet can gravitationally influence small particles that were present when that planet formed and prevent them from joining together to create a moon. This effect also creates gaps in Saturn’s rings. It’s not known for sure which possibility is correct. However, some studies of ring material suggest that rings are formed from moons that broke apart.
How do scientists study rings? Even though spacecraft like Cassini have traveled very close to Saturn, the ring particles are so small they can't image them directly. They can study rings by watching the light from a bright star pass behind the rings and flicker. The Cassini spacecraft took a series of pictures on September 9, 2006 of a red giant star slipping behind Saturn’s rings. The star’s brightness is well known, and when it passed behind the rings the light that got through can be used to study the ring particles. The spacecraft’s narrow angle camera took pictures at a distance of approximately 359,000 km which converts to 233,000 miles from Saturn.
Next time you see images or look through a telescope at Saturn be sure to appreciate the rings because they won’t be there forever. NASA claims that the rings may have less than 100 million years to live. That might sound like a long time for us, but it’s a very short time compared to the 4 billion years Saturn has been around.
You’ve been listening to Western Slope Skies, produced by the Black Canyon Astronomical Society and KVNF Community Radio. This feature was written and recorded by Yasmin Campos, an astronomy student of Dr. Catherine Whiting at Colorado Mesa University.
