The solar activity originated from a large sunspot cluster, designated AR3664, which produced several strong flares. As these CMEs reached Earth, they initiated a severe (G4) geomagnetic storm, leading NOAA to upgrade the situation to an “extreme” (G5) geomagnetic storm, marking it as one of the most powerful in over two decades. The SWPC issued a Geomagnetic Storm Watch for May 10, warning that further solar eruptions could prolong the storm conditions through the weekend.
NOAA coordinated with various operators of power grids, satellites, and navigation systems to mitigate potential disruptions. They advised these operators to take protective actions against the induced currents from fluctuating magnetic fields, which could cause blackouts or damage to infrastructure. One of the most visible effects of the severe solar storm in May 2024 was the widespread auroras. There were also notable disruptions in high-frequency (HF) radio communications. Users of these radio signals experienced degradation and temporary loss of service on the sunlit side of the Earth. This impacted navigation systems and other technologies reliant on stable communication channels.
While there were no major blackouts reported, power grid operators were on high alert and experienced irregularities. They had to manage voltage control issues and ensure that induced currents from the geomagnetic activity did not cause significant disruptions. This proactive management helped mitigate potential widespread power outages.
Satellites experienced increased drag and charging, which could affect their operations. There were reports of tracking and orientation problems for spacecraft. The elevated levels of radiation also posed risks to satellite hardware, prompting operators to take protective measures.
Courtesy of NASA/SDO and the AIA, EVE, and HMI science teams
