diumenge, 23 de desembre del 2018

NASA says Saturn’s rings are disappearing right before our eyes


Of all the planets in our Solar System, you’d have to agree that Saturn is the most immediately recognizable. With its iconic rings, you can pick Saturn out in an instant, but if NASA scientists are right, we might actually be watching the planet’s most eye-catching feature disappearing right in front of us.
In a new video, NASA Goddard explains that while we’ve always seen Saturn with its bold rings, the rings themselves are actually fairly young. Estimated to be less than 100 million years old, they’re a “new” feature of the planet, and they won’t be sticking around for long.
The rings are made up largely of frozen water, and they’re actively dumping incredible amounts of ice onto the planet constantly. A recent paper suggests that a whopping 22,000 pounds of material falls from the rings every single second, and over time that rain will bleed the rings completely dry.


The particles that make up the rings are being bombarded by radiation from the Sun and, as the video explains, clouds of plasma from impacts of space rocks. It’s those interactions that cause the material be caught up in the planet’s magnetic field and subsequently pulled down towards the planet by gravity.
NASA’s estimates of the amount of material present in the rings, combined with data on how much of it is falling, points to the rings being completely gone within 300 million years. A timeline like that means that none of us will actually be around to see Saturn in its future ring-less state, but that’s beside the point. The fact is that Saturn is rapidly heading towards another ring-free phase of its life, and that’s pretty wild.

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