Earth was struck by a mass of charged particles from the sun late Monday night, triggering a minor geomagnetic storm and dazzling displays of the Northern Lights.
While scientists had predicted a mild aurora, they were surprised when a coronal mass ejection (CME) collided with Earth's atmosphere, resulting in a G1-class geomagnetic storm.
Charged Solar Particles Trigger Rare Northern Lights Across the U.S.
A CME is a cloud of charged particles that burst from the sun, often following intense solar flares. These solar events release streams of particles that interact with Earth's magnetic field, creating the Northern Lights, also known as auroras.
According to Forbes, the latest CME followed two significant solar flares earlier this week, classified as M2 and M3.1, which occurred on Dec. 13 and Dec. 15, respectively.
Although forecasters initially believed the CME would narrowly miss Earth, updated data from the National Oceanic and Atmospheric Administration (NOAA) revealed a direct hit.
The impact was recorded at 5:19 a.m. UTC on Dec. 17. NOAA's DSCOVR satellite, which monitors solar wind, detected the incoming particles and helped confirm the event. Shortly after the collision, the geomagnetic activity reached level 5 on the Kp index, signaling the onset of a minor storm.
For skywatchers, this meant a chance to witness the Northern Lights. The aurora was visible in parts of Canada, Alaska, and northern-tier U.S. states, including Montana, North Dakota, Michigan, and Maine.
Auroras are usually confined to polar regions, but during heightened solar activity, they can extend much further south, making them visible in unexpected locations.
Minor Solar Storms Bring Stunning Auroras and Potential Tech Disruptions
Forecasting auroras remains challenging. NOAA's Space Weather Prediction Center uses real-time data to provide short-term updates, with its DSCOVR satellite offering about 15 to 30 minutes of warning. Apps like Aurora Now also help observers track geomagnetic activity and plan their viewing.
Beyond the stunning light shows, geomagnetic storms can have other impacts. Even minor storms, like this G1 event, can cause weak power grid fluctuations and minor disruptions to satellite operations.
Scientists are keeping a close watch as the sun moves toward solar maximum, the peak of its 11-year cycle, expected to occur in 2025, according to Yahoo.
This period is marked by increased sunspot activity, which often leads to more frequent and powerful solar storms.
With nearly 40 CMEs recorded last week alone, space weather experts caution that stronger storms could hit Earth in the coming months.
While most are unlikely to cause significant damage, their effects — ranging from brilliant auroras to potential technological disruptions — underscore the need for continued monitoring. For now, the recent storm serves as a reminder of the sun's dynamic and unpredictable nature.
