Cosmic countdown: Days are numbered for Saturn’s iconic rings, says NASA

Saturn's rings could vanish much sooner than expected

It's hard to let things go, but it appears that even planets have to deal with loss.

Of all the planets in our Solar System, you'd have to agree that Saturn is the most immediately recognizable. NASA says that Saturn's gravity is pulling the ice that makes up the rings "into a dusty rain of ice particles under the influence of Saturn's magnetic field".

And the results were stark: If the sheer volume of ring rain the scientists spotted during those few hours is typical for Saturn's weather forecast, that rain would eat up a huge amount of the icy rings, between 925 and 6,000 lbs. When this happens, the particles can feel the pull of Saturn's magnetic field, which curves inward toward the planet at Saturn's rings. "This is relatively short, compared to Saturn's age of over four billion years".

In an image from NASA, a view of Saturn from the Cassini spacecraft. According to a press release from NASA, Saturn really is "losing its iconic rings at the maximum rate estimated from Voyager 1 & 2 observations made decades ago". Like Earth, it has four seasons-they just last seven years like some bad Westeros world, due to its 29.4-year orbit.

This artist's conception shows how Saturn's appearance may change over the next hundred million years, as the innermost rings disappear first, raining down onto the planet, and then very slowly followed by material from the outer rings. The team at NASA is looking to see how the ring rain will change with the seasons on Saturn. "Maybe we're just in that interesting, lucky period where we get to see Saturn's rings to the level that we see them". "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". O'Donoghue and his co-authors didn't include that infall in the estimates presented in their paper, but suggested in an accompanying statement that the two phenomena combined could gorge through the rings in more like 100 million years.

"It's not out of the question, I would say, that the rings might degrade on this kind of time scale", said Jeff Cuzzi of NASA's Ames Research Center in Moffett Field, California, who was not involved in the research.

Once there, the icy ring particles vaporize and the water can react chemically with Saturn's ionosphere.

When energized by sunlight, the H3+ ions glow in infrared light, which was observed by O'Donoghue's team using special instruments attached to the Keck telescope in Mauna Kea, Hawaii.

But Cassini also found that a colossal amount of organic molecules and water ice (on the order of 22,000 pounds per second) are falling onto the planet's equator through a different, potentially transient process that could help hasten the rings' demise.

Although Cuzzi is skeptical of the time frame in the new study, he agreed it is likely that the rings will gracefully degrade as the solar system matures.



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