Radio Blackouts As 'Hyperactive' Sun Fires off Fourth X-Flare

A volatile sunspot has been spitting out solar flares this week, with four X-class flares being detected in as many days.

This sunspot, named AR3663, has a particularly explosive "beta-gamma-delta" magnetic field which is causing this surge of "hyperactive" activity, making it the most active sunspot of this solar cycle so far, according to spaceweather.com.

One of these powerful solar flares, which hit the Earth on May 6, caused a radio blackout across the Indian Ocean, with more potentially heading our way in the coming days.

The sunspot released four solar flares since May 3, with these bouts of solar radiation all being classified as X-class flares: X1.6, X1.2, X1.2, and even X4.5 on May 6.

Sunspots are fleeting dark spots on the sun's surface caused by intense magnetic activity, which inhibits convection currents in the sun by reducing the surface temperature compared to the surrounding areas. The number of sunspots on the sun can vary, with more spots generally seen during the most active period of the sun's 11-year solar cycle of magnetic activity, which we are currently approaching. The last solar minimum was in 2019, and the solar maximum is estimated to occur between now and the start of 2026.

Sunspots can sometimes have specific magnetic field alignments, with those with a "beta-gamma-delta" magnetic field being considered to have a greater potential for producing significant solar activity, such as powerful solar flares and coronal mass ejections (CMEs). These are released when the twisted magnetic field lines of the sunspot suddenly rearrange, sending bursts of solar radiation into space in the form of solar flares.

"The strength of these flares is then categorized as B, C, M, X where X is the strongest one," Daniel Brown, an associate professor in astronomy and science communication at Nottingham Trent University in the U.K., told Newsweek.

Each class is about 10 times stronger than the previous, with an X1 flare being 10 times more powerful than an M1, and 100 times more powerful than a C1 flare.

"There is a higher probability of having such flares during solar maximum—which happens every 11 years and we are approximately in that period. A severe X10-class flare could happen roughly eight times during that 11-year period. And a minor M flare can occur about 2,000 times in that cycle," Brown said.

The recent X4.5 on May 6 caused radio blackouts across the Indian Ocean, as powerful solar flares often do. This is because high-energy radiation from a solar flare increases the level of ionization in the Earth's ionosphere, which means that radio waves, especially those in the high-frequency range used for long-distance communication, cannot effectively reflect off the ionosphere to reach distant receivers, leading to attenuation or complete blocking of radio signals.

This sunspot may still throw out more X-class flares in the next couple of days, and as we approach the next solar maximum, active sunspots like these will become a more common occurrence.

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