The rings of Saturn are either giving birth to a moon, or destroying one

In a series of photos dating back to May 2012, NASA scientists have identified a bright object at the edge of Saturn's outermost ring. Nicknamed "Peggy", the object is a kilometer across and could be a moon about to calve off the rings. Or, alternately, it could be a moon that got too close to the rings and is in the process of disintegrating.

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  1. From the article ...

    "Saturn’s rings are a conveniently located dynamical laboratory," says the opening sentence of a new paper. The convenient part may be debatable, but the dynamism isn't. The rings are filled with gaps and wiggles, created by interactions among their particles and a collection of small moons that act as shepherds, their gravity ushering the rings' particles into distinctive orbits.

    These are strong claims, in light of the picture provided and our inability to perform close observations. What's interesting about scientific press releases is not always the stuff that's in the article, but also that which is left out. For instance, can gravity explain this?

    The Cassini-Huygens mission placed an observation platform in orbit around Saturn, designed to last until mid-2008. Several images of the F-ring seem to indicate a helical structure that twists around a central cylinder, rather than a braid. There are what look like three toroidal shapes visible in the image at the top of the page, with the tips of many others visible along the strand. In the center of the three helical filaments is a bright, rotating tube that shows where the forces have become concentrated.


    In 1913, Kristian Birkeland conducted his now-famous experiment where a small, magnetized iron globe was placed in a vacuum and used as the cathode in electric discharges. As he wrote about Saturn's rings: "It seems almost incredible that such a ring of cosmic dust should be able to exist for ever, so to speak, without other governing forces than gravitation..."

    Plasma physics experimenter, author and theorist Wal Thornhill wrote in agreement with Birkeland's work:

    "As shown in Birkeland's laboratory experiments, the inflowing [conventionally] electric current forms a plasma donut where the electrical energy is stored. It is that energy that drives the winds and lightning on Saturn...In fact, Saturn has two plasmoids. One is outside the rings, the other inside the rings. Discharges to Saturn must cross the rings."

    It would seem that this image showing a ringed-system created in the laboratory (the lower image) would be relevant to this press release, but notice there is no mention of any of Birkeland's work in any press releases about the rings of Saturn.

  2. Don't even mention the alien mining ship as an option, boingboing, way to GO. WHat ever happened to journalistic integrity? hee

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