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Credit: NASA/JPL/Spaces Science Institute
Jan 17, 2007
Saturn's CometThe new-found jets on Saturn’s moon Enceladus are indistinguishable from the jets on comets. Like cometary jets, they are electrical in origin and indicative of electrical activity throughout the Saturnian system.
On its recent close pass above the surface of Saturn’s moon Enceladus, the Cassini spacecraft encountered an increased density of icy particles and water vapor. The event was reminiscent of Stardust’s passage around the nucleus of Comet Wild 2, when much larger particles pelted the spacecraft.
As Cassini was leaving Enceladus, its cameras looked back to get a better view of the ice dust and vapor it had encountered. The image above is what it saw: jets, collimated jets, collimated jets like those seen on Comets Wild 2 & Hale-Bopp.
A cloud of gas in the vacuum of space will expand. If the components of the cloud have a common velocity, the expansion will produce a cone of material with decreasing density. To produce a collimated beam of gas, some mechanism is required to impart a common velocity to the molecules that is very large compared to the expansion velocity.
Such a mechanism is the finely machined nozzle in a rocket engine. Incredibly, if not absurdly, astrophysicists have proposed just such fine machining in the cavities that are presumed to generate jets on comets. But even rocket exhaust expands faster than the jets of comets—and now the jets of Enceladus.
If astrophysicists didn’t have a taboo against uttering the “e” word—“e” for “electrical”—they would have a natural explanation for jets that didn’t call for the intelligent design of comets and small moons: Birkeland currents. Plasma physicists will immediately recognize the jets of Enceladus as cathode jets. Such jets mark the current channels that impinge on Enceladus’s polar region. Those currents are electrically eroding the “tiger stripe” channels on the moon and simultaneously heating them. (As in the case of Io’s “hot spots,” temperature measurements are averaged over the area covered by a pixel. Because the currents “pinch down” where they touch the surface, the actual “hot spot” is apt to be much smaller than a pixel and therefore much hotter than the measurement indicates.)
Of course, a persistent current must be part of a larger circuit. The jets and tiger stripes that Cassini has viewed must connect with other electrical elements in Saturn’s extensive plasmasphere. If mission scientists had taken the “e” word more seriously, they might have included instruments and plans that could map that larger circuit. (It’s regrettable that taxpayers aren’t more insistent that scientists actually follow scientific methods.)
The Electrical Universe expects that the larger circuit will be similar to the circuit that produces jets on comets. The Saturnian system is not unlike stellar systems, and Saturn may be considered a cool star. (If ancient testimony is examined, our pre-historical ancestors saw it shining as a “sun of night.”) Enceladus would then be a comet in that system—a Saturnian comet.
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Please check out Professor Don Scott's new book The Electric Sky.
NOTE TO READERS: Wallace Thornhill, David Talbott, and Anthony Peratt will share the stage with other investigators of planetary catastrophe at the British Society for Interdisciplinary Studies “Conference 2007” August 31-September 2. GET INFO
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David Talbott, Wallace Thornhill
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