New ring discovered around Saturn, solves long-standing mystery

For many decades, the mystery of why Saturn's moon Iapetus has a very dark hemisphere and a much brighter one has stumped astronomers and scientists. It has been great fodder for SF authors, inspiring Arthur C. Clarke's ideas in the novel 2001: A Space Odyssey (the conclusion to which happens at Saturn, not Jupiter as in the movie). In the former the explanation is the Monolith (what else?), which is acting as a giant stargate in the surface of Iapetus, whilst in the latter Iapetus itself is revealed to be a vast alien spacecraft in disguise.


Today, it was revealed that scientists have discovered the, sadly somewhat more mundane, reason behind the mystery: Iapetus is orbiting Saturn in the on the inner edge of an absolutely vast 'new ring' of dust discovered orbiting the planet at a distance of 8 million miles. The ring is approximately 20 times thicker than the diameter of Saturn itself. The ring is being 'generated' by the outer moon Phoebe, and like that moon is in retrograde orbit. This is why the impact of the dust fragments on Iapetus is highly marked, as the fragments are hitting Iapetus with tremendous force, even though the fragments are not particularly large.