WASHINGTON (AFP) – The most powerful solar storm in more than two decades struck Earth yesterday, triggering spectacular celestial light shows from Tasmania to Britain – and threatening possible disruptions to satellites and power grids as it persists into the weekend.
The first of several coronal mass ejections (CMEs) – expulsions of plasma and magnetic fields from the Sun – came just after 1600GMT, according to the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center.
It was later upgraded to an “extreme” geomagnetic storm – the first since the “Halloween Storms” of October 2003 caused blackouts in Sweden and damaged power infrastructure in South Africa. More CMEs are expected to pummel the planet in the coming days.
Social media lit up with people posting pictures of auroras from northern Europe and Australasia.
“We’ve just woken the kids to go watch the Northern Lights in the back garden! Clearly visible with the naked eye,” Iain Mansfield in Hertford, England, told AFP.
That sense of wonder was shared in Australia’s island state of Tasmania.
The excitement spread across Europe and North America, from Mont Saint-Michel on the French coast to Payette, Idaho, where the sky shimmered with green light above the western US states.
Authorities notified satellite operators, airlines and the power grid to take precautionary steps for potential disruptions caused by changes to Earth’s magnetic field.
Elon Musk, whose Starlink satellite internet operator has some 5,000 satellites in low Earth orbit, described the solar storm as the “biggest in a long time”.
“Starlink satellites are under a lot of pressure, but holding up so far,” Musk posted on his X platform.
Unlike solar flares, which travel at the speed of light and reach Earth in around eight minutes, CMEs travel at a more sedate pace, with officials putting the current average at 800 kilometres per second.
The CMEs emanated from a massive sunspot cluster that is 17 times wider than our planet. The Sun is approaching the peak of an 11-year cycle that brings heightened activity.
Professor of space physics at the University of Reading Mathew Owens told AFP that how far the effects would be felt over the planet’s northern and southern latitudes would depend on the storm’s final strength.
