This is Scientific Americans 60 Second Science.

I'm Karen Hopkins.

When it comes to Saturn, it's the rings that render the planet instantly recognizable.

But it turns out that Saturn was not always so elaborately adorned.

Data from the final orbits of the Cassini mission indicate that Saturn's rings were a relatively

recent addition, forming a scant 100 to 10 million years ago.

The findings are in the journal Science.

During what's been called the grand finale phase of the Cassini mission, the spacecraft repeatedly dove through the gap between the top of Saturn's clouds and the innermost edge of its rings.

These flybys allowed researchers to separate the gravitational effects of the planet and its accessories,

which led to a more precise measurement of the ring's mass.

Their mass was the missing piece of the puzzle to the

to the term in their age.

Danieli Durante, a postdoc at Sapiens University in Italy who

analyzed the data.

The rings are made up mostly of ice with a small fraction of impurities, about 1 or 2 percent of the total rings mass.

These impurities consist of rocky material coming from outer space.

Since these impurities are accumulated over time, this allow us to relate the total mass of the

rings with their age.

Dorante and his colleagues found that Saturn's bling has a combined mass of about 1.5 to 2 times 10 to the 19th kilograms.

That's less than half the mass of its smallest moon.

And when they crunch the numbers, the data suggested an age of no more than 100 million years.

To put that in context, remember, dinosaurs roam the Earth from about 200 million years ago until 65 million years ago.

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