Two active zones formed on the sun


There are two sunspots in the southern hemisphere of the sun today. Their magnetic polarity reveals something interesting: they come from different solar cycles. Take a look at this magnetic map of the Sun’s surface (with an insert of sunspots) from NASA’s Solar Dynamics Observatory.

One sunspot (AR2760) refers to the old solar cycle 24, and the other (AR2761) refers to the new solar cycle 25. We know this because of the Hale polarity law. AR2760 is + / – while AR2761 is / /, the reverse signs that mark them as belonging to different cycles.

This is generally normal. Solar cycles always overlap at their borders, spraying a solar minimum with a mixture of sunspots from the old and new cycles. Sometimes, as today, they appear simultaneously. We could see more of these combinations in the coming months as we slowly make our way through one of the deepest solar lows in a century.

The simultaneous appearance of two solar cycles suggests a type of temporary equilibrium. In fact, the tipping point may already have been reached. So far this year there have been 7 numbered sunspots. Five of them (71%) came from the solar cycle 25. This is comparable only to 17% in 2019 and 0% in 2018. Slowly but surely, solar cycle 25 is returning to life.

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