How do rings form

Spokes can be longer than 10, miles 16, kilometers , greater than the diameter of Earth. But despite their size, spokes can come and go quite quickly.

They can form in the time it takes you to eat breakfast and then disappear before you sit down for lunch. The spokes were unseen from until , the year after Cassini entered Saturn orbit, which surprised scientists.

And in the spokes appeared again in full, and Cassini captured images, some of which were strung together into a video. Visit the Planetary Photojournal's ring gallery. During Saturn's equinox, when the rings face the sun edge-on, Cassini watched ring particles produce elongated shadows that revealed unexpectedly immense ring chunks that measured miles kilometers in size. Few sights in the solar system are more strikingly beautiful than softly hued Saturn embraced by the shadows of its stately rings.

JPL's lucky peanuts are an unofficial tradition at big mission events. Voyager 2 made its closest approach to Saturn on Aug. The mission revealed a planet so phenomenal scientists had to go back. New research on nine craters on Saturn's largest moon Titan provides details about how weathering affects the surface — and what lies beneath. Cassini mission data provides strong evidence that the northern hemisphere of the moon has been resurfaced with ice from its interior. Scientists have developed a new prediction of the shape of the bubble surrounding our solar system.

Uncovering Our Solar System's Shape. Planetary scientists have learned something significant: More than a quarter of the exoplanets they studied could be ocean worlds. Are Ocean Planets Common? Using data from NASA's Cassini spacecraft, scientists found Titan drifting away from Saturn a hundred times faster than previously understood.

What if the rings have always been exposed to an unchanging influx of cosmic dust, and the rings are million years old at most? Then we would have to explain how the rings formed so recently, which is a tricky prospect.

First, we have no idea what created the rings, so assigning them an origin story at any point in time is difficult. But no such mission is forthcoming. The typical thickness of the rings is only about 10 meters. But their own stories are also riddled with uncertainties, from their origins to their ages.

A model , using the current positions of the moons to peer backward through time, suggests that the present system of rings and inner moons could have been created when a pair of midsize moons smashed into each other about million years ago. While the past is unclear, the future seems more certain. The rings may look permanent, but the opposite is true. When scientists add this to the material detected by Cassini, they estimate that the rings will disappear completely in million years. Like many, he considers it fortunate that humanity and the rings coexist — giving us plenty of opportunity to argue about the secrets they hold.

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Please agree and read more about our privacy policy. Read Later. By Robin George Andrews November 21, First, they are all much wider than they are thick. The rings of Saturn, for example, are about ,km wide stretching away from the planet but only metres thick.

The other thing that all rings systems share is that they are all made of small particles of ice and rock. The smallest of these particles are no bigger than dust grains, while the largest of the particles are about 20 metres in diameter — about the size of a school hall.

All the rings around the planets also contain gaps that are sometimes many kilometres wide and at first nobody could figure out why. We later learned that the gaps were caused by small moons that had gobbled up all the material in that particular part of the ring system.

The biggest difference between the rings of Saturn and the other gas giant planets is that the particles that make up the rings of Saturn are very good at reflecting the light from the sun back towards the Earth.

That means they appear to be very bright, which is why we can see the rings from Earth using a normal telescope. The particles that make up the rings of Uranus and Neptune contain elements that were darkened by the sun. This is an exciting time for astronomy. More and more satellites and space probes are being launched from all over the world , which allows us to investigate the outer planets of our solar system.