Radio Blackouts Could Hit US Today Due to Solar Flares

The sun just erupted with a powerful X-class solar flare, causing radio blackouts across the Atlantic Ocean.
The flare, which hit X2.3-class in strength, was emitted at 8:40 a.m. ET from a sunspot named AR3883. The resulting blackout mainly affected South America, but more powerful solar flares could be on their way, possibly causing blackouts over the U.S.
Sunspot AR3883, as well as AR3886, are primed to release even more solar flares as they move across the sun’s surface to face toward the Earth. In fact, there is a 35 percent chance of X-class solar flares occurring Wednesday, Thursday and Friday, with an 80 percent chance of M-class flares.
“Solar activity is expected to be moderate with continued M-Class (R1-R2/Minor-Moderate) flaring and a chance for X-Class (R3-Strong) levels 06-08 Nov. Solar flare probabilities are being driven by Regions 3883 and 3886 due to their magnetic complexities,” NOAA’s Space Weather Prediction Center said in a three-day forecast.
Solar flares are sudden, intense bursts of radiation from the sun’s surface, typically as a result of magnetic energy that has built up in the solar atmosphere being suddenly released from sunspots or active regions.
“X-rays are always coming from the Sun, but a flare converts magnetic energy in the atmosphere of the Sun into (among other things) X-rays. As an explosive event, it can cause the X-ray level at Earth to go up dramatically, factors of at least a thousand or so as in this M-class event, or even more in X class flares,” Martin Connors, a professor of space science and physics at Canada’s Athabasca University, told Newsweek.
Solar flares are classified by their intensity, with the categories being A, B, C, M and X, where X-class flares are the most powerful. Each class is 10 times more powerful than the last, and more powerful flares are less common. According to the Space Weather Prediction Center, M-class flares are seen around 2,000 times per 11-year cycle, while X-class flares occur about 175 times per cycle. Flares more powerful than X10-class are only seen eight times per cycle.
The most powerful flare in this cycle so far was an X9.0-class flare on October 3 this year, and before that, it was an X8.79 flare on May 14.
Solar flares cause radio blackouts at frequencies below 30 MHz due to them ionizing the Earth’s ionosphere.
“This can seriously affect the normally present level of ionization (breakdown of atoms) in the ionosphere at 80 to 100 (and more) km above us and change what we are used to in how radio waves propagate, usually for the worse,” Connors said.
Usually, this atmospheric layer reflects high-frequency radio waves, bouncing them from their source to their destination, but if the flare ionizes that layer, these waves become degraded, or are completely absorbed, leading to a radio blackout. The intensity of the blackout depends on the strength of the solar flare: more powerful flares cause wider, more severe blackouts. These blackouts usually only affect the sunlit side of the Earth, where the ionosphere is directly impacted by the flare’s radiation.
If the active sunspots facing towards our planet flare off more solar flares, and the U.S. happens to be in the firing line, more radio blackouts could occur across the country.
The largest flare ever thought to have occurred in recorded history was the 1859 Carrington Event flare.
“It is believed that the most significant solar storm event happened in 1859 and is generally referred to as ‘The Carrington Event.’ Back then we didn’t have critical digital infrastructure, similar to what we have today,” Rami Qahwaji, a visual computing professor and space weather researcher at the University of Bradford in the U.K., previously told Newsweek.
“But an event similar to the Carrington Event happening today could result in between $0.6 and $2.6 trillion in damages to the U.S. alone, according to NASA spaceflight.”
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