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

Saturn’s rings are a young age at just 400 million years old — just a fraction of the planet’s 5 billion years of existence.

An international team of physicists has the most compelling evidence to date that could pinpoint the rings’ origins long after the planet formed 4.5 billion years ago, answering a question that has puzzled scientists for centuries.

To make their findings, the team of scientists looked at the constant deluge of space dust, or micrometeoroids, that accumulate in tiny layers throughout the solar system, including on the boulders and ice blocks that make up Saturn’s rings.

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

Dr. Kempf said, “Think of the rings as the carpet in your house. If you have a clean carpet lying around, all you have to do is wait. Dust will settle on your carpet. The same goes for the rings.’

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

The Cassini spacecraft, which spent 13 years in orbit around Saturn, was equipped with an instrument called the Cosmic Dust Analyzer — essentially an advanced bucket.

It could pick up particles as minute as a virus and examine their electrical charge, size, chemical composition and their speed through space.

From 2004 to 2017, the team collected just 163 dust particles that originated outside Saturn’s immediate vicinity; an infinitely small amount, but it was enough.

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

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

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

His telescope wasn’t nearly as powerful as those astronomers use today, but in the years that followed, stargazers determined that those jug-like bulges 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 attempted to answer this question, after concluding that the rings could not possibly consist of a single solid element, but rather numerous “unconnected particles.”

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

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

Dr. Kempf said, “In a way, we’ve closed a question that started with James Clerk Maxwell.”

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

Although they are not expected to disappear completely in the next 100 million years, they are constantly losing material.

Continuous bombardments from micrometeorites and the sun’s radiation electrify the particles that make up the rings, align with Saturn’s magnetic field and follow its invisible path as it orbits the planet.

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

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

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

WHAT DID CASSINI DISCOVER DURING HIS 20-YEAR MISSION TO SATURN?

Cassini launched from Cape Canaveral, Florida, in 1997, spent seven years on the road, followed by 13 years in orbit around Saturn.

An artist’s impression of the Cassini spacecraft studying Saturn

In 2000, it studied Jupiter for six months 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 swept over the planet for nearly a year.

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

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

There it discovered eerie hydrocarbon lakes made of 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 embarked on its second mission (Cassini Solstice Mission) that 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 beyond our solar system.

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

Cassini didn’t just study Saturn – it also captured incredible images of its many moons. Saturn’s moon Enceladus can be seen floating in front of the rings and the small moon Pandora in the above image. It was captured on November 1, 2009, with the entire scene illuminated by the sun

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

In April of this year, it completed its closest flyby of Titan and began orbiting the Grande Finale, which ended on September 15.

“The mission has changed the way we think about where life evolved beyond our Earth,” said Andrew Coates, head of the Planetary Science Group at the Mullard Space Science Laboratory at University College London.

“Besides Mars, outer planet moons such as Enceladus, Europa and even Titan are now the strongest contenders for life elsewhere,” he added. “We completely rewrote the textbooks on Saturn.”