NASA Space Science News, September 29, 1998
Gamma ray flash zaps satellites, illuminates Earth
A powerful flash of gamma rays, strong enough to be detected through a satellite's own shielding and to turn night into day in the Earth's outer atmosphere, has led to confirmation of the existence of super-Magnetized Stars. ... If the theory holds up, it will mean that there are probably a million old magnetars drifting around our Galaxy, and perhaps as many as 10 to 100 million, because magnetars must have been forming throughout the history of our Galaxy. Most of these stars have now gone inactive and are difficult to detect.
The flash of gamma rays was detected on Aug. 27 by at least seven spacecraft in Earth orbit and in deep space. It capped several months of observations of an object known as SGR 1900+14, a Soft Gamma Repeater located in the constellation Aquila (the eagle) near Sagittarius (the archer). ... Astronomers think the Aug. 27 boomer was caused by an out-of-control magnetic field realigning itself in a manner similar to what happens inside solar flares. While in magnetars their huge magnetic field is capable of cracking a neutron star's rigid surface to bits, it also connects three different mysteries. Each mystery involves neutron stars. A neutron star is created when a massive star explodes in an event called a supernova. The remaining core of the supernova, which has slightly more mass than our own sun but can no longer burn fuel, compresses under gravity into a neutron star about 20 km (12 mi) across.