Text: Scientists have found that a rare and enigmatic class of neutron stars, of which only five are known, are actually magnetars -- exotic stars with magnetic fields trillions of times stronger than the Sun's or Earth's, so powerful that they could strip a credit card clean 100,000 miles (about 160,000 kilometers) away. These neutron stars, called Anomalous X-ray Pulsars (AXP), had defied physical explanation since the first such object was discovered in 1982. The newly exposed AXP-magnetar relationship is featured in the September 12 issue of Nature, based on data obtained with NASA's Rossi X-ray Timing Explorer spacecraft. The finding, by a team led by Prof. Victoria Kaspi of the McGill University Department of Physics in Montreal, Canada, essentially doubles the number of known magnetars. "People have suspected for years that these bizarre AXPs might be magnetars," said Kaspi, "but at last we have definitive proof. We finally caught one bursting, just like a magnetar." Joining Kaspi on this observation is Fotis Gavriil, lead author on the Nature article and a graduate student in the Physics Department of McGill University, and Peter Woods of the National Space Science and Technology Center in Huntsville, Ala. A neutron star is an ultra-dense sphere approximately 10 miles (16 kilometers) wide, the core remains of a collapsed star once roughly ten time more massive than the Sun. Neutron stars that emit steady pulses of X-ray radiation with each rotation are called X-ray pulsars. AXPs have been labeled "anomalous" because scientists have been unable to determine their energy source. Other types of neutron stars shine by virtue of either gravitational or rotational energy, options that are simply not available to AXPs. Mysteriously, AXPs are also extremely dim or completely undetectable in any other region of the electromagnetic spectrum except X rays. The AXPs' source of X rays, this latest Rossi Explorer observation demonstrates, is magnetic energy.

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