Strong solar storm hits South Africa

The South African National Space Agency (Sansa) has warned that a strong geomagnetic storm is expected over the weekend that can disrupt communications and navigation systems.

There was also a small chance it might cause the reappearance of the Southern Lights over South African skies.

South Africans had a rare glimpse of the Aurora Australis or Southern Lights on 10 May this year during the “Mother’s Day Storm”.

“Thursday’s event was the strongest Earth-facing solar flare recorded by Sansa in the past seven years and measured X9.05,” the space agency stated.

Sansa explained that solar flares are measured in five categories: A, B, C, M, and X — with X being the strongest. 

“Thursday’s X9 flare impacted high-frequency radio communications, resulting in a total radio blackout over the African region, which lasted for up to 20 minutes,” it said.

“The origin of this storm is a solar flare that erupted from sunspot 3842 on Thursday, 3 October at 14h18.”

Sansa said it had been monitoring sunspot region 3842 since Sunday, 29 September 2024, when it appeared on the Sun’s visible disk.

It said the sunspot is about 1.5 times larger than the Earth’s surface area.

“The sunspot produced several significant solar flares and associated coronal mass ejections (CMEs), which are waves of charged energetic particles,” said Sansa.

“These waves of energetic particles will impact Earth over the weekend, causing geomagnetic storms.”

The impact of the CME recorded on 1 October was expected to hit South Africa from Friday, 4 October 2024, with Sansa forecasting a minor (G1) storm.

“The CME recorded on 3 October, associated with the major X9 flare, is expected to impact the Earth on Saturday, 5 October 2024,” Sansa said.

“Geomagnetic conditions are expected to range from G1/Minor to G3/Strong, with storm levels possibly reaching G4/Severe storm throughout the day.”

Sansa space weather boss Mpho Tshisaphungo said the chances of seeing the Southern Lights this time were unfortunately low.

She explained that the aurora is only visible during the night and with no cloud cover. It is also dependent on the strength of the geomagnetic storm.

“Geomagnetic storms can have a severe impact on communication and navigation systems as well as the power grid,” Sansa warned.

“Industries using these systems should take note of possible disruptions over the weekend.”

The Sun is heading toward an 11-year peak in activity called solar maximum.

Live Science reports that the latest flare was the 42^nd X-class CME of 2024, whereas there were only 36 X-class events during the previous nine years.

It noted that the number of geomagnetic storms and auroras could surge further over the next few months.

This is because Earth’s magnetic field became more closely aligned with the solar wind around the equinox, which occurred on 22 September.

The alignment means there is a higher chance of a CME hitting the Earth’s magnetosphere, causing a geomagnetic storm.

Researchers have also warned that sunspot AR3842 could emit more powerful solar flares in the coming days.