Sun’s magnetic field to reverse completely - NASA

The sun flipping its magnetic field occurs around once every 11 years. Picture: Complimentary
The sun flipping its magnetic field occurs around once every 11 years. Picture: Complimentary
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THE SUN’S magnetic field is set to reverse completely some time in the next few months, NASA has revealed.

The polarity of the vast magnetic field surrounding our nearest star is going to flip in no more than three to four months, according to measurements from NASA observatories.

This massive event will cause ripples throughout the solar system, being felt even by the Voyager probes out in the extremes of our solar system. The ‘heliosphere’, the region where the sun’s magnetic influence can be felt, extends billions of kilometres beyond Pluto.

Closer to home, the change will whip up extreme space weather around Earth, which could cause disruptions to satellite and radio communications. The changes could also alter the Earth’s climate by changing the amount of cosmic rays that arrive in our atmosphere, thought by some scientists to affect cloudiness.

This 180 degree flip is part of a natural cycle, and happens approximately every 11 years. The upcoming flip will be the mid-point of what scientists call ‘Solar Cycle 24’. During the reversal the magnetic field weakens and becomes more variable, before the north and south poles swap.

“The sun’s north pole has already changed sign, while the south pole is racing to catch up,” said Phil Scherrer, solar physicist at Stanford University, California. “Soon, however, both poles will be reversed, and the second half of [the] solar max will be underway.”

Since measurements began in 1976, three of these grand reversals have been recorded using instruments called ‘magnetograms’, based at the University of Stanford’s Wilcox Solar Observatory.

The observatory is one of the only places in the world which monitors the magnetic fields at the sun’s poles, and will continue to do so until the reversal occurs.