PureInsight | January 20, 2003
[PureInsight.org] Using NASA's Rossi X-ray Explorer satellite, astronomers have identified the most powerful magnetic star known in the universe. The star, named SGR 1806-20 and first observed 25 years ago, is 40,000 light years away from Earth. Its magnetic field is extremely powerful, and the strength of its magnetic field is approximately 100 billion Tesla. In comparison, the Sun's average magnetic field varies between 1 and 5 Gauss, which is less than 10-3 Tesla, and that of the earth is even smaller. With such a strong magnetic field, it has a force strong enough to stop a locomotive made of iron dead its tracks from as far away as the distance between the Moon and the Earth.
The star is one of the unusual neutron stars classified as magnetars. Neutron stars are compact spheres that are the remains of larger stars. Scientists can estimate the magnetic fields by observing the movement of charged particles around the magnetic star or measuring the spin rate of the star along with the spin-down rate, that is, the rate at which the star's spin is slowing. Although SGR 1806-20 is only one of such magnetars identified so far, scientists believe there are numerous similar stars in the universe.
This new discovery is due to the efforts of scientists from several universities in the USA and Canada and from NASA. The discovery was published in two articles in Astrophysical Journal Letters. Scientists are now trying to come up with a theory to explain the origin of such magnetars.
Reference: http://www.gsfc.nasa.gov/topstory/20021030strongestmag.html
Translated from: http://www.zhengjian.org/zj/articles/2002/12/20/19695.html
