The suns magnetic field is expected to flip in the next 3 to 4 months. If that sounds cataclysmic, dont worry. It happens every 11 years at the peak of each solar activity cycle and the suns internal dynamo reorients itself. Once the change happens, well be at the midpoint of the 24th observed solar cycle with the solar maximum behind us.
When the the flip happens, the magnetic field dies down slowly, then reaches zero before emerging again with a reversed polarity. The effects of this flip-flop are felt throughout the solar system, as a ripple in the magnetic field that reaches all the way to the limits of the heliosphere.
The current sheet is a region of electrical current created by the magnetic field extending from the suns equator out billions of kilometers, and its at least 10,000 kilometers wide in most places. The current is small just one ten-billionth of an amp per square meter, but theres a lot of surface area. In fact, the entire heliosphere is organized around the current sheet.
As the suns magnetic field reverses, the current sheet will become wavy. Objects orbiting the sun, like Earth, pass into and out of the densest part of the current sheet, which can stir up unexpected space weather and cause brighter auroras on Earth. The wavy current sheet also serves as a better barrier from cosmic rays, the dangerous high-speed particles from distant supernova explosions.
The suns north pole is already far along the way losing its polarity, with the south racing to catch up. Before you know it, they switch will happen and well see solar activity fall for a few years before it amps up again. The same thing will happen 11 years from now, and 11 years from then. It will be that way until the sun becomes a very different kind of star in the distant future.
Now read: NASA finds frothy magnetic bubbles at the edge of our solar system
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