This computer-generated animation by Roy Prol imagines the Earth as a ringed planet, such as Saturn or Uranus. First, it addresses the orientation of the rings, and then shows what they would look like from various places around the world, day and night. In Scientific American, John Matson writes that Earth may have once had a ring system:
But such a ring, if it were to suddenly appear, might not be all good news. Decades ago, John O'Keefe of the NASA Goddard Space Flight Center ventured that Earth may have had a ring system similar to Saturn's for a brief period. In a 1980 paper in Nature, O'Keefe pointed to climatic data indicating colder winters at the end of the Eocene epoch some 34 million years ago along with showers of tektites, glassy rocks of mysterious origin, at around the same time. O'Keefe's theory held that tektites that missed the Earth in this bombardment were captured into a ring system that may have persisted for millions of years, casting a winter shadow across Earth's surface and contributing to a late Eocene die-off of many marine organisms such as plankton and mollusks.
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