Something strange is happening inside the Sun. In the last 40 years, the pattern of tiny sound waves produced deep beneath the surface of our star has mysteriously changed, say scientists reporting in the Monthly Notices of the Royal Astronomical Society.
This solar activity fluctuates in intensity in reliable 11-year cycles, at times driving solar flares, geomagnetic storms and aurorae (its highs and lows are shown in this composite image). But scientists are now recording “significant” and “marked” changes at various stages of that pattern, and note the Sun could be shifting to “a different mode of behaviour”.
That could have repercussions here on Earth.
“The Sun has its own ‘active biorhythm’ creating rising and falling magnetic activity that shapes space weather,” says lead author William Chaplin—and changes in space weather can disrupt satellites, GPS and communications, as well as power grids.
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