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Triple North Pole

Triple North Pole

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 It might surprise you to know there are actually three North Poles: the geographic, the magnetic, and the geomagnetic. The one we most commonly think about is the Geographic North Pole—the tip of the axis that the globe spins around. It’s in the middle of the Arctic Sea, on pack ice, above more than 2 miles of water. During the summer, when the pole is tilted toward the sun, it’s 24-hour daylight. In the fall, the sun finally sets—once, and only once, per year. That brings on 6 months of night, until springtime, when the once-annual sunrise starts another 6 months of day. The North Magnetic Pole is slightly to the south. This is where Earth’s magnetic field, which springs out of the ground at the South Magnetic Pole, dives back into the ground. Its exact location, however, is constantly changing, because Earth’s magnetic field is always changing. Today, magnetic north is moving about 34 miles a year, gradually traveling toward Siberia. Finally, there’s the North Geomagnetic Pole—the northern axis of the magnetosphere, the magnetic shield that protects us from solar winds. If you imagine the magnetosphere as a ball around a bar magnet, with the bar running through Earth, this pole would be the positive end. It’s currently 700 miles south of the Geographic North Pole but also always traveling. With three dark places to look in the dead of winter, and two of them moving, it’s a wonder Santa ever makes it home.
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