"It was as if night was briefly turned into day in the iono-sphere," said Umran Inan, professor of electrical engineering at Stanford and head of the research group that observed the atmospheric disturbance. During the five minutes that the gamma- and X-ray radiation impinged on Earth's upper atmosphere, the researchers found that the level of ionization or electrical activity in the ionosphere, which is normally quiescent at night, suddenly flared to daytime levels.

The wave of gamma- and X-ray radiation and high-energy particles came from a cataclysmic magnetic flare on a star 20,000 light years away. Such immense magnetic forces, scientists think, are strong evidence supporting the existence of a strange type of astronomical body called a magnetar, a special kind of neutron star. A neutron star is the collapsed core that is left behind when a massive star explodes. It is extremely dense, weighing more than the sun but squeezed into a ball less than 12 miles in diameter.

While the radiation, released in August, never reached the ground and posed no health hazards, scientists said that it stripped atoms of their electrons and disrupted the quiet of the high night sky with electrical conditions that severely limited the range of radio transmissions. It rocked delicate
instruments on at least seven spacecraft, causing temporary shutdowns.

For more information contact http://hail.stanford.edu/gammaray.html