NOAA Raises Risk of Strongest Solar Flares Amid High Sunspot Activity

There is a higher-than-usual chance of powerful X-class solar flares on Wednesday, thanks to several active sunspots kicking up a fuss on the sun's surface.

September 27 is showing a 15 percent chance of X-flares and a 40 percent chance of M-flares, according to NOAA's Space Weather Prediction Center. Only a week ago, on September 20, chances of X-class flares were around 5 percent.

This is a result of ten sunspot groups with mixed-polarity magnetic fields facing toward the Earth, making them a ticking time bomb for powerful flares. Solar flares are bursts of X-ray radiation from the sun's surface, with the power of the flare depending on the amount of magnetic energy that has built up and been released.

Solar flares can cause radio blackouts on Earth, as the X-rays of a flare ionize the ionosphere layer of the atmosphere, preventing radio signals from being bounced off that layer between sender and receiver.

"In general, a flare is a substantial release of energy from the sun and specifically an active region or sun spot," Daniel Brown, an associate professor in astronomy and science communication at Nottingham Trent University, told Newsweek.

"These are caused by magnetic field lines becoming more and more twisted storing energy like a rubber band, and at some stage, they snap and rearrange. That results in a massive release of electromagnetic radiation and also material from this region.

"In some cases, this might be so bright that while safely observing the sun, you can see the brightening. You can sense the twistedness of magnetic field lines from the complexity and shape of the sunspots as well as seeing how the polarity of the sunspots is. Close proximity of a positive and negative sunspot/magnetic field lines is a strong candidate to cause a flare."

Solar flares are classified as A, B, C, M, or X, depending on how powerful they are, with X-class flares being the most powerful and least common. X10 flares are 10 times more powerful than X1 flares. "The most powerful of these X-class flares have been compared to release energy comparable to billions of hydrogen bombs," Brown said.

"Such X-class flares can cause prolonged radiation storms, which can impact satellites," Brown explains. "There is also the chance that airline passengers near the poles suffer small radiation doses. These flares could also possibly create global transmission problems and worldwide blackouts, however, this would be highly localized and specific to certain communication channels, e.g. shortwave radio."

More powerful solar flares like X-flares are more common as the sun approaches its solar maximum, which happens at the peak of the sun's 11-year solar cycle. The next solar maximum is forecast for 2025, meaning that we are nearing the sun's most active period of the cycle.

"Flares tend to be more common as the Sun reaches its maximum activity levels which wax and wane on an 11-year cycle," Alan Woodward, a professor of computer science and space weather expert at the University of Surrey told Newsweek. "We've observed something like 200 flares per cycle in the past. We are a couple of years from the next solar maximum, so we expect to see the number of flares, and their strength, increase over the coming years. We've had X class flares already this year, and there probably be more, but I doubt most ever noticed."

The most powerful X-flare on record occurred in 2003, measuring in at a staggering X28, but the Carrington Event in 1859 is thought to have been the most severe solar flare in history.

"In that strongest ever Carrington Event there were reports of telegraph lines sparking with the voltages induced in them," Woodward said. "If that were to happen today you can imagine just how much electronic equipment we depend upon and extrapolate how it is disruptive on earth.

"Probably more immediate would be the impact on space-based systems as they don't have the protection of the atmosphere. Satellite safety is one of the reasons the solar weather watchers report as they do: it helps operators prepare their craft to withstand any flare."

Luckily, the chances of a flare this powerful hitting the Earth again are very, very low.

"The chances of a flare affecting the Earth are lessened because the flares pop out in all directions decreasing the chance of them hitting Earth," Woodward explained. "The concern is if such a flare did ever affect the earth directly. It might be [a] 15 percent chance of one erupting but the chance it would come our way is much lower."

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