Reconnection, the merging of magnetic field lines of opposite polarity near the surface of the sun, Earth and some black holes, is believed to be the root cause of many spectacular astronomical events such as solar flares and coronal mass ejections, but the reason for this is not well understood. Researchers at Los Alamos National Laboratory now have a new theory that may explain the instability and advance the understanding of these phenomena.
Theorists Giovanni Lapenta of Los Alamos National Laboratorys Plasma Theory group and Dana Knoll of the Labs Fluid Dynamics group presented their findings at the American Geophysical Union meeting in San Francisco at the Moscone Convention Center.
The theory is based on a 19th century mathematical observation called Kelvin-Helmholtz instability. "What we are trying to determine is why magnetic field lines loop out from the surface of the sun, reconnect and then fall back," said Lapenta. "And why these systems, which look very stable, are in fact quite unstable."
Kevin Roark | EurekAlert!
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