Northern Lights Explained by NASA

 - Jul 25, 2008
NASA scientists have finally explained the mystery behind the Northern Lights phenomena after a year long study.

Northern Lights (aurora borealis) are natural colored light displays that dance across the sky in spectacular shapes and colors, particularly in the north and south polar zones. Typically, these northern lights occur every two or three days.

According to the findings, the substorms that cause the sudden brightening and rapid movements of the northern lights are the results of energy explosions that happen a third of the way between Earth and the moon. These substorms are triggered by magnetic reconnection, “A common process that occurs throughout the universe when stressed magnetic field lines suddenly snap to a new shape, like an overstretched rubber band.”

“Magnetic reconnection releases the energy stored within these stretched magnetic field lines, flinging charged particles back toward the Earth's atmosphere,” said David Sibeck, THEMIS project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

“They create halos of shimmering aurora circling the northern and southern poles.”