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Take A Good Look, Saturn's Losing Its Rings At 'Worst-Case-Scenario' Rate

If you're weighing up the pros and cons of immortality, pop "may have to live with a ringless Saturn" on the negative list.

According to new NASA research, the planet's trademark rings may be disappearing at a rate faster than scientists expected, potentially leaving the old girl ringless in just 100 million years.

No doubt that's a long time for us, but when you consider the planet has been spinning for about four billion years, it's a mere blink of the cosmological eye in the sky.

Saturn's rings-- which are only about 10 metres thick-- are made up predominately of chunks of water ice which range in size from microscopic grains to boulders.

Based on ground-based observations by Keck Observatory telescopes in Hawaii, O'Donoghue's team may have confirmed this water ice is being pulled into Saturn by gravity, triggering what is known as "ring rain".

It's a theory that's been around for decades, following observations made by NASA's Voyager missions which were launched in the 70s.

"We estimate that this 'ring rain' drains an amount of water products that could fill an Olympic-sized swimming pool from Saturn's rings in half an hour," lead author James O'Donoghue, a space physicist at NASA's Goddard Space Flight Center, said in a statement.

"But add to this the Cassini-spacecraft measured ring-material detected falling into Saturn's equator, and the rings have less than 100 million years to live."

The Cassini spacecraft ended its 20-year mission in 2017 by "death diving" into Saturn's atmosphere, recording data until the last second. Its final orbits of the region between the planet and its rings detected ring rain at the equator falling much faster than previously thought.

A Fleeting Beauty

Both O'Donoghue's findings and the observations from Cassini also help to answer the long-held question of whether Saturn was born with its halo or acquired it later in life.

A series of images captured by Cassini were composed into the largest, most detailed, global natural-colour view of Saturn and its rings ever made. Image: Getty/NASA

Some scientists believe the rings were formed as the planet was four billion years ago, while others suggest it was a much later addition, potentially formed when small, ice moons orbiting around the planet collided.

But if the rings really do only have 100 million years left as the study suggests, it may be the case the planet wasn't born with them, as it's unlikely something so fragile would have survived the previous multiple billion years.

"We are lucky to be around to see Saturn's ring system, which appears to be in the middle of its lifetime," O'Donoghue said.

"However, if rings are temporary, perhaps we just missed out on seeing giant ring systems of Jupiter, Uranus and Neptune, which have only thin ringlets today!"