A massive ball of plasma and accompanying magnetic field ejected from the sun is expected to strike Earth on Thursday morning, potentially triggering auroras as far south as Alabama, according to U.S. forecasters.
The phenomenon, known as a coronal mass ejection (CME), is traveling through space at approximately 4 million kilometers per hour. As it approaches Earth, the Space Weather Prediction Center has issued a level 4 geomagnetic storm watch (G4), one level below the highest possible G5 seen in May.
\"The current anticipation is that it is going to arrive tomorrow morning to midday, Eastern time, and perhaps continue on into the following day,\" Shawn Dahl of the Space Weather Prediction Center told reporters at a briefing on Wednesday.
The sun is approaching—or possibly at—the peak of its 11-year cycle, when solar activity is heightened. In May, Earth experienced its most powerful geomagnetic storms in two decades, producing colorful displays across night skies far from the poles.
Geomagnetic storms occur when CMEs collide with Earth's magnetosphere, potentially disrupting satellites, radio signals, and GPS positioning systems. They can also impact electricity grids; for instance, the \"Halloween Storms\" of October 2003 sparked blackouts in Sweden and damaged power infrastructure in South Africa.
Dahl mentioned that the Federal Emergency Management Agency (FEMA), already managing the aftermath of Hurricane Helene and the approaching Hurricane Milton, has been informed, along with companies operating the North American power grid, so they can take necessary mitigation steps.
May's storms disrupted precision GPS systems used by U.S. farmers across the Midwest and caused some high-voltage transformers to trip, though without large-scale disruption to the grid. Dahl added that around 5,000 satellites had to adjust their orbital levels because the storm inflates the ionosphere, causing them to slow down and de-orbit.
For those living in the right latitudes—potentially as far south as northern California or Alabama in the U.S.—the auroras would be most visible away from city lights and in the darkest skies possible. Experts suggest using cameras or smartphones to capture the displays, as modern digital imagery can often pick them up even when the naked eye cannot.
Reference(s):
cgtn.com
