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Rocky Meadows, age 11, of Fletcher, N  C  ,‑

Do we know what caused Saturn's rims?

Now is a good opportunity to take a little time from tracking satellites and use our small telescopes to behold the wonder of Saturn’s rings  The great planet is high in the sky right after sunset, following the saddlebag constellation of Sagittarius and the sprawling Scorpius over the sky  There are now two starry‑eyed planets in this region one behind the other  The front one is Saturn, the other is giant Jupiter, bright as a street lamp 

If you have practiced at focusing even a small telescope, you can make it show you the rings like a fuzzy belt around the waist of the big planet  Galileo glimg$ed them with the first little telescope ever trained on the skies  He saw them as two hazy bumps like a pair of ears  Some 50 years later, there were better telescopes and the rings could be seen as they really are  Since then, the astronomers have kept a regular record of the razzle‑dazzle rings and the different views we get of them 

Meantime the astronomers have learned more of the laws which govern the heavenly bodies and keep them 3  n their places  The pulling power of a pla;cistis gravity is directly related to its mass, or the matter it contains  The more massive a planet is, the greater its pull of gravity  The power of gravity, however, decreases with distance, A distant moon or satellite may escape the pull of a planetts gravity and go off on its own 

These and other heavenly traffic laws were used to calculate the nature of Saturnts rings and the facts are very different from what our eyes seem to tell us  In a good telescope, the golden circles, one inside the other, look like bands of shimmering gold, so solid that they cast a black shadow on the yellow planet below them  The laws of gravity, however, make this impossible 

Solid, or even liquid bands so near to the planet would be disrupted by giant tides and torn to pieces by the force of gravity 

It was first guessed and later proved that the rings are made from separate particles, each orbiting the planet  The entire system of rings is about 20 times wider than our world, yet our moon is 100 times heavier  According to heavenly traffic laws, a small moon would be torn apart if it came within about 90,000 miles of Saturn  The outer rim of the ring system is about 86,000 miles above the planet, which means that it is entirely within the smash‑up area  The nine moons of Saturn are in the safe region, way beyond the shimmering rings 

Many people have used these and other facts to try and guess the origin of the ring system  They may have formed from a small moon which shattered when it came too aloes to its parent planet, On the other hand, some experts think that moons grow by amassing bits of floating dust and debris between the planets  The rings may be a swarm of this material, so close to the planet that the pull of gravity prevents it from forming a solid moon  The dazzling rings may be an old, broken‑down mourn or an unborn moon  And again, they may have an entirely different origin which no one has yet guessed 

For the latest  information go to Science news for kids in Main Menu and click on the Jet Propulsion web site

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