Good news for aurora hopefuls

I had assumed that the recent very extensive aurora, which I would quite like to see but live too far north, would not likely be repeated any time soon.   However, as explained by the Washington Post this weekend, it is likely we are going to have a repeat in the next couple of years:

The displays so far have been quite the warm-up. On May 10, when Pegram saw her first aurora, Earth was hit by the biggest geomagnetic storm in about two decades, with the most widespread aurora in probably 500 years. The storm was rated a severity level of 5 on a scale of 5, according to the National Oceanic and Atmospheric Administration. But at least seven other storms have reached a 4 since 2019....

Scientists won’t confirm when the peak month of solar activity is until a few months after it’s passed — like waiting for all contestants of a race to compete before declaring a winner. But they know we’re getting close.

About every decade or so, the sun’s north and south magnetic poles flip, which affects the solar activity seen at the surface. This “solar cycle” means some years are more active on the sun’s surface than others, usually measured by the number of dark blotches called sunspots. More visible sunspots mean more active, magnetically complex regions on the sun that can spawn flares and explosions. Not all of these sun’s eruptions hit Earth, but it’s like adding more darts to a dart board game — there are more chances one will land....

When the cycle does reach the other side of the maximum, it will be good sign for aurora chasers. The biggest geomagnetic storms tend to occur in the year or two after reaching the maximum, a phenomenon known as the Gnevyshev gap, said McIntosh, vice president of space operations at Lynker and formerly the deputy director of the National Center for Atmospheric Research.

“The real fun of the solar cycle is not now. It’s what comes in the next few years,” he said. “The storms get more complex, more frequent, and that makes them a bit more impactful for Earth.”

Coming off its solar maximum, the sun becomes a complex, muddy mess. As tendrils of the next solar cycle move in, it can merge with the old solar cycle. McIntosh said the two systems have different polarities and can get tangled with each other. When the systems merge, the pluses and minuses start to realign to make the simplest configuration. But as it goes through this intricate spaghetti rearrangement, enormous amounts of energy are released.