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Scientists Find Trigger For Northern Lights

Posted by timothy on from the when-aliens-are-tickled dept.

daftna writes "The New York Times (registration required) is reporting that NASA researchers 'have identified the trigger for the colorful electrical storms in the polar regions ... Scientists knew two events that occur in the tail of the magnetic field during substorms, but did not know which event acted as the trigger for the auroras.'"

2 of 97 comments (clear)

  1. That was quick by Anonymous Coward · · Score: 5, Informative

    THEMIS launched in the first half of 2007. I remember because my plasma physics professor canceled class the day of the launch and invited us to the launch party...

    The cause of the aurora borealis is something that has not been adequately explained up to now. It seems that magnetic reconnection phenomena in the tail are the trigger, but where exactly? That's what THEMIS was designed to figure out.

    This is a very interesting result for plasma physicists and astrophysicists.

    http://ds9.ssl.berkeley.edu/themis/flash.html
    http://www.nasa.gov/mission_pages/themis/main/

  2. The result, for those who care... by jnik · · Score: 5, Informative

    It's buried at the end of the article, but Near Earth Neutral Line wins, current disruption loses. The real kicker is that the aurora were detected before the cross-tail current was disrupted, so the auroral currents are apparently not caused by closure of the cross-tail current. That should be very interesting.

    The mission planners had the foresight to include a substantial ground-observation component, which made this second result possible.