University of Iowa professor: Solar Flare biggest in more than a decade

If metaphorical snow overtook your radio Wednesday morning or your navigation system steered you astray, don't blame the devices.

Turn your eyes skyward for the guilty party - although experts advise you don't look right at it.

The sun, which last month captivated the country with its disappearing act, apparently enjoyed the attention. Because early Wednesday it released two massive solar flares - the second marking the largest in more than a decade.

'This can have an effect on the Earth, and it did have an effect on the Earth,” Greg Howes, associate professor in the University of Iowa Department of Physics and Astronomy, told The Gazette.

The first flare, which occurred at 4:10 a.m. in Iowa, registered as an X-class solar flare - the most powerful sun-storm category - and was the strongest since 2015. Three hours later, at 7:02 a.m., an even bigger flare registered - the strongest since 2006, according to the National Oceanic and Atmospheric Administration. Both came after a smaller flare on Tuesday.

The NOAA space weather prediction center in Boulder, Colo., recorded the flares, which occur when raging magnetic storms smash together and undergo something called 'magnetic reconnection.”

'It's like breaking a rubber band, and it snaps back, and it releases a huge amount of energy,” Howes said.

That accelerates electrons toward the surface of the sun, causing them to emit X-rays.

'The larger the magnetic fields that undergo this reconnection, the larger the solar flare that erupts,” Howes said. 'And what it is, it's a bright flash of X-rays that essentially radiates the entire solar system on that side of the sun.”

On the side of the Earth facing the sun, according to Howes, the X-rays ionize atoms in the upper atmosphere - essentially 'ripping apart electrons from atoms and creating electrons and ions.”

'It increases the number of electrons and ions by a huge amount - it's what is called an ionization storm in the upper atmosphere,” he said.

And it can actually cut off radio communication, affecting folks using DirectTV or aircraft radio communications.

'Low-frequency radio, like when we listen to AM or FM radio, can be affected,” he said. 'In addition to that, a lot of us depend on GPS navigation, and it can also disrupt GPS navigation signals, and it did that this morning.”

GPS systems aren't cut off completely, according to Howes. But the quality is degraded.

'Just like the hazy radio reception, if that's the data that's telling you your position, its affectively giving you a very fuzzy position,” he said.

Solar flares aren't all bad. When they involve something called 'coronal mass ejections,” or what Howes calls 'magnetic tsunamis,” giant clouds of solar plasma are blown away from the sun.

'It's almost like a volcanic eruption of plasma,” he said.

The billions of tons of plasma that escape from the sun and shoot through the solar system at 1 million to 2 million mph can reach Earth in one to three days. When that occurs, according to Howes, they create 'beautiful glowing aurora in the sky” - like the Northern Lights near the North Pole.

Some of those can be seen from Iowa if the sky is clear. And, although researchers don't yet know if an ejection accompanied Wednesday's solar flares, one did occur with the smaller flare on Tuesday.

That means sky gazers across Iowa could spot some aurora this week.

'What we don't know is whether the powerful solar flare that occurred this morning also had an accompanied magnetic tsunami,” Howes said Wednesday. 'If it did, we might see some really spectacular aurora displays tomorrow night.”

Although scientists aren't worried about any catastrophic events with these solar flares, some in the past have generated geomagnetic storms on Earth, affecting electric power grids. Geomagnetic storms have created blackouts that can last a day or even a few days.

'If such an event were to happen today ... and it can happen, the concern is that it could cost hundreds of billions of dollars in damage,” he said. 'It could knock out dozens of transformers.”

l Comments: (319) 339-3158; vanessa.miller@thegazette.com