“Frequencies below 5 Mhz were most affected, and navigation signals degraded,” Strong wrote.
Solar radiation can ionize the upper atmosphere, which makes for spectacular aurora borealis. However, it’s also where high-frequency radio waves travel. So when high-energy solar radiation strikes, it can cause those radio signals to degrade.
The flare that struck Earth on Monday was an X1. 5 flare, NASA reported.
X-class flares are the most intense types of solar flares, and a strong one can expose astronauts and space passengers traveling over polar regions to potentially harmful radiation as well as damage satellites, per Space.com. “The current event, a mild category 1, should, however, be rather harmless,” Space.com reported.
The X-class flare peaked at 4:46 p.m. On Monday, ET. Two days earlier, on August 5, another solar flare peaked at 6:21 p.m. ET.
Why solar flares keep hitting Earth
Solar cycles typically last about 11 years. The sun has a cycle of low and high activity.
Right now, the sun is growing more active, inching closer to peak activity, aka solar maximum.
That peak in solar activity was expected in 2025. But a surprising increase in the number of sunspots this year and the frequency of solar flares suggests that the peak could come sooner than expected — at the end of 2023.
The last solar maximum, between 2012 and 2014, was fairly weak compared to typical solar maximums. A strong solar max can lead to extreme space weather, such as back-to-back X class solar flares.
This year’s X-class solar flares have been on the lower end of the intensity spectrum, with the biggest, an X2. 2, occurring in February.
While this year’s flares have routinely affected radio signals, a solar flare of X28 — like the one detected in 2003 — would be incredibly destructive for Earth’s technology. More-intense flares can damage the power grid, destroy satellites, and scramble GPS.