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Cause of Aurora Borealis Confirmed

An anonymous reader writes "There are reports that satellites have aided scientists in confirming why the Aurora Borealis (Northern Lights) exists. 'New data from NASA's Themis mission, a quintet of satellites launched this winter, found the energy comes from a stream of charged particles from the sun flowing like a current through twisted bundles of magnetic fields connecting Earth's upper atmosphere to the sun. The energy is then abruptly released in the form of a shimmering display of lights.'"

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  1. The More Important Discovery by pln2bz · · Score: 5, Interesting
    The interesting new information is actually the following:

    "THEMIS encountered its first magnetic rope on May 20, 2007," says Sibeck. "It was very large, about as wide as Earth, and located approximately 40,000 miles above Earth's surface in a region called the magnetopause." The magnetopause is where the solar wind and Earth's magnetic field meet and push against one another like sumo wrestlers locked in combat. There, the rope formed and unraveled in just a few minutes, providing a brief but significant conduit for solar wind energy. Other ropes quickly followed: "They seem to occur all the time," says Sibeck.

    What happens within the laboratory with *electrical* plasmas is that the plasma will tend to form filaments of charged particles. It is a natural state of the plasma. Furthermore, multiple filaments will tend to possess long-range attraction and short-range repulsion with one another. In other words, they will twist around one another without fully combining. This can be observed by any layperson by looking closely at the point where your novelty plasma globe's filaments touch the glass. What appears as one filament from a distance is in fact two filaments twisting around one another like a rope that unwind with contact to glass. This roped structure within the laboratory constitutes a flow of charged particles, and as those charged particles move across the rope in response to voltage potentials, this flow of charged particles will in turn create helical magnetic fields around the filaments. Maxwell's Equations demand it.

    The observation of a roped magnetic structure connecting the Sun and Earth is extremely important because we know from our laboratory experiences with plasmas that rope-like structures occur when the plasma is electrical. I'm very curious what the response will be from the astrophysical community about this *structure*. Will they argue that the similarity in morphologies is actually coincidental?

    If so, somebody should share the talking points with NASA, because they appear to be off-message ...

    From http://www.nasa.gov/mission_pages/themis/auroras/northern_lights.html:

    "THEMIS also has observed a number of small explosions in Earth's magnetic bow shock. "The bow shock is like the bow wave in front of a boat," explained Sibeck. "It is where the solar wind first feels the effects of Earth's magnetic field. Sometimes a burst of electrical current within the solar wind will hit the bow shock and--Bang! We get an explosion."
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    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.