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Saturn’s rings are a ‘new phenomena’ at 400million years old

Saturn’s ring’s are a young age of only 400million years old — just a fraction of the 5billion years the planet has existed for.

An international team of physicists has the most compelling evidence to date that would pin the origins of the rings as coming about long after the planet formed 4.5 billion years ago, answering a question that has dogged scientists for centuries.

To reach their finding, the team of scientists looked to the constant deluge of space dust, or micrometeoroids, that build up in small layers throughout the solar system, including on the boulders of rock and ice that comprise Saturn’s rings.

Led the University of Colorado, Boulder, scientists spent 13 years collecting a minuscule amount of dust while measuring the rate at which it accumulated on the planet’s rings, a process which they equated to telling the age of a house by running a finger along its surfaces.

Dr Kempf said: ‘Think about the rings like the carpet in your house. If you have a clean carpet laid out, you just have to wait. Dust will settle on your carpet. The same is true for the rings.’

The image of Saturn was taken by the Hubble Telescope 

The 2004 Cassini mission, launched by NASA in collaboration with the European Space Agency and the Italian Space Agency to study Saturn and its rings, provided a unique opportunity for Dr Kempf and his fellow physicists.

The Cassini spacecraft, which spent 13 years orbiting Saturn, was outfitted with an instrument called the Cosmic Dust Analyzer – essentially a sophisticated bucket.

It could pick up particles as minuscule as a virus and investigate their electrical charge, size, chemical makeup, and their velocity through space.

From 2004 to 2017, the team collected a mere 163 dust grains that originated from outside Saturn’s immediate neighborhood; an infinitesimal amount, but it was enough. 

Based on their calculations, published Friday in the journal Science Advances, the team concluded that Saturn’s rings have likely been accumulating dust for only several hundred million years.

The mystery surrounding Saturn’s rings has weight on astronomers for centuries. 

The rings were first discovered by Italian astronomer Galileo Galilei in 1610 who used a telescope and noted the sixth planet from the sun had ‘ears’, or elongated bulges on either side of the planet.

His telescope was not nearly as powerful as those astronomers use today, but in the years that followed star gazers determined that those jug-handle-like outcroppings were actually rings. It wasn’t until the 19th century that the material that makes up Saturn’s rings came into question.

Scottish mathematician James Clerk Maxwell set out to answer this question, having concluded that the rings could not possibly be made up of one solid element, but rather countless ‘unconnected particles’.

He proved mathematically that the force of gravity would break a thin body orbiting Saturn and predicted that the rings were composed of particles that floated around the planet.

For most of the 20th Century, it was believed that the rings likely formed at the same time as Saturn.

Dr Kempf said: ‘In a way, we have closure on a question that started with James Clerk Maxwell.’

And in an unexpected twist, the planet’s rings could be vanishing. 

While they’re not expected to disappear completely for about 100 million years, they are losing material constantly.

Constant bombardment from micrometeorites and the sun’s radiation electrifies the particles that make up the rings, lining up with Saturn’s magnetic field and following its invisible path as it spirals around the planet.

But when the particles come too close to Saturn’s atmosphere, gravity sucks them in, creating a phenomenon that astronomers call ‘ring rain.’

Dr Kempf considers the fact that the Cassini spacecraft was able to capture the ephemeral features incredibly fortunate, though it does not answer the question of how those rings formed in the first place.

He said: ‘If the rings are short-lived and dynamical, why are we seeing them now? It’s too much luck.’


Cassini launched from Cape Canaveral, Florida in 1997, then spent seven years in transit followed by 13 years orbiting Saturn.

An artist's impression of the Cassini spacecraft studying Saturn 

An artist’s impression of the Cassini spacecraft studying Saturn 

In 2000 it spent six months studying Jupiter before reaching Saturn in 2004.

In that time, it discovered six more moons around Saturn, three-dimensional structures towering above Saturn’s rings, and a giant storm that raged across the planet for nearly a year.

On 13 December 2004 it made its first flyby of Saturn’s moons Titan and Dione.

On 24 December it released the European Space Agency-built Huygens probe on Saturn’s moon Titan to study its atmosphere and surface composition.

There it discovered eerie hydrocarbon lakes made from ethane and methane.

In 2008, Cassini completed its primary mission to explore the Saturn system and began its mission extension (the Cassini Equinox Mission).

In 2010 it began its second mission (Cassini Solstice Mission) which lasted until it exploded in Saturn’s atmosphere.

In December 2011, Cassini obtained the highest resolution images of Saturn’s moon Enceladus.

In December of the following year it tracked the transit of Venus to test the feasibility of observing planets outside our solar system.

In March 2013 Cassini made the last flyby of Saturn’s moon Rhea and measured its internal structure and gravitational pull.

Cassini didn't just study Saturn - it also captured incredible views of its many moons. In the image above, Saturn's moon Enceladus can be seen drifting before the rings and the tiny moon Pandora. It was captured on Nov. 1, 2009, with the entire scene is backlit by the Sun

Cassini didn’t just study Saturn – it also captured incredible views of its many moons. In the image above, Saturn’s moon Enceladus can be seen drifting before the rings and the tiny moon Pandora. It was captured on Nov. 1, 2009, with the entire scene is backlit by the Sun

In July of that year Cassini captured a black-lit Saturn to examine the rings in fine detail and also captured an image of Earth.

In April of this year it completed its closest flyby of Titan and started its Grande Finale orbit which finished on September 15.

‘The mission has changed the way we think of where life may have developed beyond our Earth,’ said Andrew Coates, head of the Planetary Science Group at Mullard Space Science Laboratory at University College London.

‘As well as Mars, outer planet moons like Enceladus, Europa and even Titan are now top contenders for life elsewhere,’ he added. ‘We’ve completely rewritten the textbooks about Saturn.’