Saturn Is Losing Its Rings In A ‘Worst-Case Scenario’ Deterioration

Don't worry, they aren't likely to be gone in your lifetime.

a stock photo of saturn
MarcelClemens / Shutterstock

Don't worry, they aren't likely to be gone in your lifetime.

Saturn is losing its rings – the one feature that has defined the planet ever since humans first gazed upon them in the 1600s, the journal Physics is reporting. In fact, so quickly are they disappearing that the space community is calling it a “worst-case scenario.”

Venus has its clouds of ammonia gas. Mars its rusty surface that gives it the nickname the red planet. Jupiter has its great red spot. And now Saturn’s identifying feature is going away, gradually being torn apart by the massive planet’s gravitational pull.

The rings, composed largely of dust particles, rocks, and ice, are being sucked back to the planet’s surface by gravity. So strong is the planet’s gravitational pull that the amount of ice pulled in could, if it were converted to liquid water, fill an Olympics-sized swimming pool in thirty seconds, says James O’Donoghue of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Scientists have known about this “ring rain” for decades, ever since it was first observed by the Voyager spacecraft in the 1980s. However, the original estimates as to how long it would take for the rings to disappear are now considered way off. That’s because the Cassini probe found ring material in the planet’s upper atmosphere – more than should have been there and accumulating faster than it should have been.

Still, that doesn’t mean that any human alive today will live to see the rings disappear – it will still be tens of millions of years before that happens.

“The rings have less than 100 million years to live. This is relatively short, compared to Saturn’s age of over 4 billion years.”

In fact, humans appear to have gotten lucky in terms of when we appeared on Earth in space history. That’s because not only are Saturn’s rings disappearing, but they haven’t always been there, either. We evolved the means to look at those rings during the billion or so year period during which they’re fully-formed and still present. Other planets in the solar system, namely Jupiter, Uranus, and Neptune, all have “ringlets” that are in the beginning stages of their lives. In a few hundred million years or so, whatever intelligent life that may remain on this planet will be able to look through their telescopes and see fully-formed rings on those planets.

Saturn has, of course, been observable in the night sky since long before humans evolved. But it wasn’t until 1610 when Galileo Galilei turned a primitive telescope toward Saturn. Even then, he wasn’t fully aware of what he was seeing; four decades later, in 1655, Christiaan Huygens was the first to describe Saturn as being orbited by a ring-shaped “disc.”