NASA has been monitoring a strange anomaly in Earth's magnetic field: a giant region of lower magnetic intensity in the skies above the planet, stretching out between South America and southwest ...

Such is the case with the Earth's magnetic field. Every so often, our planet's magnetic poles reverse polarity (see When Compasses Point South). Compass needles have always pointed north ...

As the time line at right shows, hundreds of times in our planet's history the polarity of the magnetic shield ensheathing the globe has gone from "normal," our current orientation to the north ...

Scientists believe the Sun’s magnetic field could reverse within our lifetime, a natural cycle that occurs roughly every 11 years. While this solar polarity shift is not dangerous, it can impact ...

The pre-fab encoder disks don’t have individual magnets—they’re just a puck of magnetic slurry that gets its polarity on the assembly line. [Erich] reverse-engineered a disk and found the ...

The change of magnetic polarity from 0 to 1 or 1 to 0 on a magnetic disk or tape. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.