As 2024 draws to a close, the skies over parts of the United States may offer a dazzling display of nature’s fireworks in the form of the aurora borealis, or northern lights, thanks to heightened solar activity.
On Sunday, two X-class solar flares erupted from the sun in rapid succession, triggering radio blackout events. These powerful flares ionized Earth’s upper atmosphere, causing shortwave radio disruptions centered around Australia.
The flares—classified as X1.1 and X1.5—originated from a sunspot on the sun’s surface, the latter of which was so powerful it even triggered a secondary explosion in another sunspot nearly 125,000 miles away.
Earlier on Sunday, another eruption on the sun sent solar material hurtling towards Earth, which is expected to generate northern lights on New Year’s Eve.
The northern lights in northern Alaska. A strong geomagnetic storm will light up the US skies on New Year’s Eve.
The northern lights in northern Alaska. A strong geomagnetic storm will light up the US skies on New Year’s Eve.
Mike Beauchamp/Getty
“There have been multiple M-Class and X-Class solar flares in recent days that are forecast to make at least a glancing blow to the Earth’s magnetosphere sometime over the next 48-72 hours between Monday night and Wednesday night,” Brandon Buckingham, a meteorologist at AccuWeather, told Newsweek.
“Because of the multiple solar flares and the degree of uncertainty of the speed at which they will travel towards the Earth, the forecast timeframe for a potential impact from a CME is rather wide even though the onset of the event is expected to be soon.”
Solar flares occur when the sun’s intense magnetic fields twist and reconnect, releasing vast amounts of energy.
These flares are typically linked to active regions on the sun, which are often visible as sunspots—areas where the magnetic fields are most concentrated and dynamic.
Flares are classified by their intensity, starting with the smallest, B-class, and progressing through C, M, and the most powerful, X-class.
Much like the Richter scale for earthquakes, this classification system is logarithmic, with each step representing a tenfold increase in energy. An X-class flare is therefore 10 times stronger than an M-class flare and 100 times more intense than a C-class flare.
The two X-class flares were determined to not have an Earth-directed component by the Space Weather Prediction Center (SWPC), meaning they won’t cause auroras. However, a G3 (Strong) geomagnetic storm watch has been issued for December 31 due to the anticipated arrival of a coronal mass ejection (CME) released earlier on December 29.
CMEs, eruptions of solar material, can interact with Earth’s magnetic field to create geomagnetic storms. These storms, if strong enough, produce spectacular auroras visible at lower latitudes.
“The aurora may be visible over many of the northern states and some of the lower Midwest to Oregon,” the SWPC said.
A map shows where auroras are likely to be visible across the U.S. on Tuesday. Solar material is set to interact with Earth’s atmosphere, generating impressive views for those in northern regions.
A map shows where auroras are likely to be visible across the U.S. on Tuesday. Solar material is set to interact with Earth’s atmosphere, generating impressive views for those in northern regions.
NOAA Space Weather Prediction Center
Auroras occur when charged solar particles interact with Earth’s magnetic field, traveling down its lines toward the poles. Upon entering the atmosphere, these particles collide with gases such as oxygen and nitrogen, releasing energy as vibrant colors of light.
The predominant green hues often seen in auroras are characteristic of oxygen, while nitrogen can produce purples, blues and pinks.
Rare scarlet-red auroras occur during particularly energetic events.
Unlike the electromagnetic energy from solar flares, which reaches Earth a matter of minutes after an eruption and can cause radio blackouts, CMEs take longer—usually a couple of days or so.
For your best chances of seeing the Northern Lights tomorrow night, head out to a dark location far from city lights and look northwards. It’s best to let your eyes fully adjust to the darkness for about 20 minutes.
Cameras are much better at picking up auroras than our eyes, so even if you can’t see it yourself, you might be able to catch a spectacular New Year’s Eve picture.
“One factor aiding in the potential to see the lights is that we are currently in a New Moon phase, allowing the night sky to be very dark,” Buckingham said.
“Unfortunately, over the next few days, clear skies will be tough to come by across the northern tier of the United States, likely making it very difficult for widespread viewing ability.”
Buckingham pointed to the northern Plains (Dakotas, eastern Montana) as the best place to catch a glimpse of the auroras on Tuesday evening.
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Auroras Set to Light Up US Skies for New Year’s Eve
