Cycle 25? Not Quite Yet…

There’s been some hopeful excitement among sunspot watchers that a group of sunspots observed in late August with reverse magnetic polarity to most of the solar cycle 24 sunspots might signal the start of cycle 25. However, the ARRL Letter says the Royal Observatory of Belgium’s Solar-Terrestrial Centre of Excellence has splashed cold water on that theory (the water vaporized instantly, of course!).

Solar Dynamics Observatory photos of sunspot groups 2720
and 2719 last summer. The white areas indicate a positive
magnetic field while the black areas are negative. Normally,
they are opposite of each other on different sides of the solar
equator (in the center of the photo), but group 2720 was
reversed. This is sometimes a sign of a new solar cycle.
However, the Royal Observatory of Belgium says these
sunspots were too close to the equator to indicate the start
of cycle 25. (NASA SDO Image)

The center noted that while the magnetic polarity of sunspots typically reverses with a change of cycle, spots from a new cycle also need to originate in the mid-solar latitudes, “typically 20° to 40° from the equator.” The sunspots in this group were observed at only about 8° solar latitude. The center says every sunspot cycle has several dozen reverse polarity sunspots that are identified with the current cycle despite being magnetically “upside-down.”

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