A compact reincarnated star packs the universe's most powerful magnet, capable of wiping out computer disks, making credit and debit cards unusable and sucking loose change into its vortex from as far away as the moon, according to new research by a Canadian scientist and her international colleagues.

Luckily, humans are immune to the electrodynamic tricks of the star known as SGR 1806-20, whose magnetic field is a thousand trillion times stronger than the Sun's. It is 40,000 light-years away from Earth and its effects can't penetrate the atmosphere.

Understanding its huge magnetic capacity, however, should shed light on stellar evolution, according to University of Manitoba professor of astronomy Samar Safi-Harb, whose research confirmed the star's magnetic strength.

"There were suspicions that this was a strong magnetic-field star. We were able to directly measure its magnetic field," she said yesterday of the research she co-wrote in the most recent issue of the Astrophysical Journal.

The neutron star with the killer magnetism belongs to a quirky class of stars called soft gamma-ray repeaters, first discovered in 1979. Since then, only four such stars have been conclusively identified, three of them in the Milky Way.

It is believed that SGR stars are born from the death of much larger stars in a supernova explosion. These compact and highly magnetized progeny are about the size of Winnipeg, very hot and volatile, and composed of neutrons.

Theorists have long speculated that these peculiar stars would be home to the universe's strongest magnetic fields, so intense they wrinkle the crust of the star. This leads to regular starquakes, which emit low-energy gamma rays into the galaxy that can flood scientific equipment in space.

Prof. Safi-Harb, a former NASA researcher, said she felt she knew how to calculate and confirm the immense magnetic fields of these bodies, which even scientists have a habit of calling "weird stars."

Working with a doctoral student from the University of Washington, Prof. Safi-Harb started to analyze gigabytes worth of data taken by a NASA X-ray satellite in 1996 during a starquake of SGR 1806-20, the most active of the new stars. Hidden in the X-ray spectrum was information that allowed the researchers to calculate the strength of the magnetic field, measured in a unit called a gauss, as one million trillion gauss. (That's written with 15 zeros.) The Earth's magnetic field measures 0.6 gauss at the poles.

Now, Prof. Safi-Harb hopes to measure the magnetic fields of the other three weird stars and begin to unravel what it all means to the quirky world of quantum electrodynamics.

"It allows us to understand physics in extreme conditions. We know such magnetic fields cannot exist on Earth," she said.