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Northern lights unleash outburst of color in skies over U.S., Europe

A G3 geomagnetic storm, featuring energy from the sun, was responsible for the colorful outburst

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Updated November 6, 2023 at 10:51 a.m. EST|Published November 6, 2023 at 10:50 a.m. EST
The aurora borealis in Bratislava-Devin, Slovakia on Sunday evening. (Frantisek Baxa via SpaceWeather.com)
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The skies across large areas of North America and Europe turned red, pink, purple and green on Sunday evening and night amid a colorful visitation of the aurora borealis, or northern lights. Parts of Australia also witnessed the aurora australis, or southern lights.

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At least a faint glow — mainly visible through long camera exposures — reached as far as south as Texas and North Carolina, with more vibrant displays near the U.S.-Canada border that were visible to the naked eye.

Inciting the display were a pair of coronal mass ejections (CMEs) — eruptions of solar plasma and energy that launch off magnetically disturbed regions on the sun. That energy propagates through space like a targeted cannonball. If it hits Earth, our planet’s magnetic field transforms that potentially hazardous energy into visible light — the aurora. The lights usually congregate around the poles, but if a CME is particularly intense, they can spill southward.

One or more CMEs arrived around 2 p.m. Eastern time on Sunday. Since the sun was still up over North America, the timing favored skywatchers in Europe and Asia. Deep reds occupied the skies over Slovakia, while rose-colored pillars painted the skies like luminous brushstrokes in Hungary. In Croatia, one photographer reported that “it was clearly visible to the naked eye, [with] colors, curtains, movement, everything” perceptible for about 15 minutes. And predictably stunning displays dazzled folks closer to the Arctic Circle, like in Norway.

In Western Australia, the southern lights danced for “hours on end,” with columns that resembled enormous neon signs in the sky.

In parts of the Mid-Atlantic in the United States, photographers captured a Stable Auroral Red (SAR) which is a band of broad, diffuse red light that remains stationary and mostly colorless during geomagnetic activity.

Amid the northern lights show, some people observed a phenomenon known as STEVE — which is short for “Strong Thermal Emission Velocity Enhancement.” It’s not the same thing as the northern lights but appears as a long, slender purple-and-white arc. It is fainter and narrower, and occurs at lower latitudes than most auroras.

Sightings of STEVE were mostly reported in Ireland and northern England.

Ahead of these displays, forecasters at the Space Weather Prediction Center in Boulder, Colo., had warned of the potential for a “moderate” geomagnetic storm rated G2 on its 1 to 5 scale. This episode wound up reaching the G3 or “strong” tier for some time, though it had simmered to G2 by the time darkness settled over the United States.

When the geomagnetic storm began on Sunday afternoon, it initially wasn’t clear if both of the CMEs — an initial weaker one and then a more significant one — had overlapped into one “shock wave” of sorts. There was some speculation that the main CME hadn’t arrived yet, and that worse geomagnetic storming would be expected later. In retrospect, it appears that the second, more intense and faster CME probably caught up with the weaker “appetizer” CME and overtook it, with both energetic pulses slamming Earth Sunday afternoon Eastern time.

The main CME was what space weather forecasters call a “full halo” event. Looking at the sun from NASA’s SOHO, or Solar and Heliospheric Observatory — a satellite in space — the burst of solar material can be seen punching into space at all angles. That’s because the CME was directed at Earth.

The most significant episodes of the northern lights are usually associated with CMEs, which most commonly emanate from sunspots — bruiselike discolorations on the surface of the sun. Sunspots are most numerous every 11 years during the peak of the “solar cycle,” which will probably peak in 2024. This means many more solar storms are likely over the next year or so and there will probably be more opportunities to view the lights.

Early this year, magnificent displays of the northern lights were seen in September, April and March.

Check out these photos captured from around the world from Sunday’s memorable event.

Europe

Australia

United States

Alaska

California

Illinois

Oklahoma

Michigan

North Carolina

Pennsylvania

Virginia

Wyoming

Canada

Kasha Patel and Jason Samenow contributed to this report.

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