The display came after the sun sent four bursts of plasma, known as coronal mass ejections or CMEs, hurtling toward Earth earlier this week. Space weather forecasters had expected three of the blasts would combine into an intense “cannibal” CME that could trigger auroras unusually far south into the United States and Europe.
Satellite observations showed limited sign of enhanced auroral activity early Thursday evening. The first hint of a storm arrived later in the evening, but even then only as a minor ripple in the atmosphere.
Then a prolonged lack of notably colorful skies much of the night caused those awaiting northern lights to become increasingly anxious. Was it becoming a bust?
Not unlike storm chasers, the most patient and persistent of sky watchers were rewarded in the end.
The strong geomagnetic storm got underway around 5:45 a.m. on the East Coast of the United States. It ramped up to G3 by 6:30 a.m. and, as that happened, an eruption of red and green pillars in the sky became visible to the naked eye much farther south than usual.
So far, reports of auroras have come in from as far south as Arizona. Nebraska, Iowa. Connecticut and Massachusetts also caught a glimpse, in addition to the typical spots in more northern reaches. Even with a moon nearly 90 percent illuminated, just days after a full moon, the colors shined brightly.
Despite some delay in the onset of northern lights, forecasts ended up fairly accurate in the end. Space scientists had been expecting a strong geomagnetic event for days.
The most intense solar storms can cause significant disruptions on Earth, including blackouts in radio communications and global positioning satellites, or even power systems more broadly. Storms of G3 intensity tend to produce only minor impacts to technological infrastructure while often producing shows of brilliant auroras.
How long will the solar storm last?
The multiple CMEs may allow auroras to be more prolonged than in most space weather events. While uncertain, it’s possible that the ongoing storm will persist into Friday night for the United States. In the meantime, other regions may witness dazzling displays, as night returns to Asia and Europe.
The #aurora I’ve been waiting for! The strong CME hit and a G3 magnetic storm occurred.
In the field quick edit from Spooner, Wisconsin. Colors straight off camera. No color correction! Bit dimmer to the eye, But the reds were so bright right into dawn!#wiwx #northernlights pic.twitter.com/h50CqazDAL— Jake Stehli (@eljakeo30) December 1, 2023
The sun continues to move through an active spell over recent months and years. November featured a strong G3 storm in which northern lights were visible on long exposure imagery as far south as Texas. Earlier in the year, a severe G4 storm struck. It was the strongest since 2017.
Additional bursts of geomagnetic activity are a good bet in the months to come as the solar cycle reaches its peak in 2024.
Dr. Sarah Adams is a scientist and science communicator who makes complex topics accessible to all. Her articles explore breakthroughs in various scientific disciplines, from space exploration to cutting-edge research.
