An intense solar storm is set to hit the Earth on Thursday, causing aurora borealis father south than usual, as the Sun is currently close to its cyclical peak of activity, a US agency has announced.
The peak of this cycle, which occurs every 11 years, led in May to the most ‘extreme’ solar storm since 2003, caused by a series of coronal mass ejections (CMEs) from the Sun.
When these particles arrive on Earth, they disrupt the planet's magnetic field, sometimes resulting in impressive aurora borealis, but also degrading high-frequency communications, disrupting satellites and overloading the power grid.
Shawn Dahl from the space weather agency attached to the US National Oceanic and Atmospheric Administration (NOAA) told journalists the solar storm was expected to arrive between Thursday morning and noon, i.e. between late morning and mid-afternoon GMT, and could possibly continue until Friday.
With particles travelling at a speed of four million kilometres per hour, this corresponds to a Level 4 geomagnetic storm on a scale of 5, according to the agency. May's solar storm reached Level 5.
More precise forecasts will only be available 15 to 30 minutes before impact, when the storm crosses the dedicated satellites.
According to Dahl, the federal disaster response agency, FEMA, which is already under pressure to manage the consequences of the deadly hurricane Helene and the arrival of its dangerous successor Milton, has been informed.
Managers of the North American electricity grid have also been informed so that they can take the necessary measures to avoid overloads.
In October 2003, a ‘Halloween’ solar storm plunged whole swathes of Sweden into darkness and damaged energy infrastructure in South Africa.
In May, farmers in the Midwest, an area in the north of the United States, observed malfunctions in their GPS systems, and the storm caused problems with high-voltage transformers, without causing any massive disruption to the power grid, Dahl said.
The orbital level of more than 5,000 satellites had had to be corrected because of the disturbances.
Rare auroras were observed in Belgium and other European countries.
