Space weather can ignite a glowing aurora in the night sky while simultaneously driving destructive electric currents toward power infrastructure on the ground within minutes, phys.org reported.
Earth stays immersed in a continuous stream of charged particles known as the solar wind. On occasion, the sun ejects a much larger cloud of charged particles and magnetic fields called a coronal mass ejection.
When this ejection reaches Earth, it interacts directly with the planet’s magnetosphere. If the magnetic fields align favorably, solar wind drags connected field lines around the dark side of the planet, stretching them far out into space to form the magnetotail.
Magnetic energy builds continuously inside this tail until the pushed lines finally draw close enough to reconnect. That explosive release of stored energy is called a substorm, occurring roughly 28,000 to 40,000 miles away from Earth.
Researchers investigating these events combined data from NASA spacecraft including THEMIS alongside NOAA’s GOES geostationary operational environmental satellites. They paired this satellite telemetry with ground-based measurements from a dense network of magnetometers spread across Arctic Canada.
When the stretched magnetic field lines snapped back into place on the nightside, instruments recorded an abrupt shift in the local magnetic field. A burst of energetic particles then raced toward Earth, with ground-level magnetic fields beginning to change sharply just seven minutes later.
Those energetic particles collide with oxygen and nitrogen atoms between 56 and 93 miles overhead to create visible auroras. At the same time, the activity drives intense electrical currents through the upper atmosphere.
Rapidly shifting upper-atmospheric currents induce powerful geomagnetically induced currents directly in the ground and in utility lines. Those induced flows can trip circuit breakers and physically damage transformers.
Auroras and ground disturbances do not hit every region at the exact same moment. Observations show the effects typically ignite at lower latitudes before spreading toward the North Pole over a span of 20 to 30 minutes.
Nearby monitoring stations often record wildly different responses. Sites separated by only tens or hundreds of miles can register massive magnetic swings on one end and weak disturbances on the other.
That local variance depends entirely on atmospheric conductivity overhead—which shifts with sunlight and auroral intensity—and ground conductivity beneath the soil, governed by local geology and moisture levels. Seeing a vibrant aurora overhead does not automatically guarantee that the ground directly below is absorbing the strongest magnetic currents.
Severe space weather has repeatedly demonstrated its capacity to cripple ground infrastructure. During a March 1989 geomagnetic storm, auroras reached as far south as Texas while shifting magnetic fields triggered the total collapse of the Hydro-Québec power system, leaving over six million people without electricity for roughly nine hours.
A comparable event struck during the October 2003 Halloween storms, bringing auroras across Europe while induced currents sparked a blackout affecting roughly 50,000 people in Malmö, Sweden. The May 2024 geomagnetic storm stressed the electrical grid in southern Sweden, forcing a vital transmission link to disconnect and temporarily halting power flow through that sector.
