The Northern Lights are heating up: could they reach all 50 states?
(NEXSTAR) – Recent intense activity on the Sun has resulted in multiple appearances of the Northern Lights across much of the United States. A recent geomagnetic storm made the brilliant streaks of color visible as far away as Alabama, a rare event could become more frequent.
According to the National Oceanic and Atmospheric Administration, about every 11 years there is a geomagnetic storm strong enough to send the Northern Lights to the southernmost parts of the United States Space Weather Forecast Center.
The late April event that brought the aurora to the southern United States was triggered by a coronal mass ejection (CME) and solar flare.
This is largely thanks to the current solar cycle, dubbed Solar Cycle 25. It started in December 2019, according to Rob Steenburgh, a space scientist at NOAA’s Space Weather Prediction Center. During this cycle, an 11-year period, the Sun will flip its magnetic poles and cause space weather, “variations in the space environment between the Sun and Earth,” which include CMEs.
CMEs are explosions of plasma and magnetic material from the Sun that can reach Earth in as little as 15 to 18 hours, NOAA explained. Accordingly NASACMEs can create currents in the earth’s magnetic fields that send particles to the north and south poles. When these particles interact with oxygen and nitrogen, they can produce auroras.
“It’s essentially the sun shooting a magnet into space,” Bill Murtagh, SWPC program coordinator and veteran space weather forecaster, tells Nexstar. “This magnet influences the earth’s magnetic field and this large interaction occurs.”
This interaction is called a geomagnetic storm. The strength of the geomagnetic storm will affect how far south the northern lights will be visible.
As Murtagh explains, the SWPC uses a scale similar to those used to measure tornadoes or hurricanes to categorize the strength of a geomagnetic storm.
According to the scale, a small G-1 storm, will cause auroras to be frequently visible in the Upper Peninsula of Maine and Michigan. A moderate G-2 storm can easily carry the Northern Lights south to New York and Idaho.
When a storm reaches G-3 status, the aurora can be seen as far south as Illinois and Oregon. Should it reach G-4 strength, residents of Alabama and Northern California could have a chance to see the Northern Lights. Solar activity that causes a G-5 storm, the highest possible on the SWPC scale, is known to produce auroras in Florida and even southern Texas.
One such storm in September 1859 – known as the “Carrington Event” according to Murtagh – was so violent that residents of Cuba, Central America and parts of the Caribbean were able to see the auroras. Some weren’t quite as impressed as they were today, fearing the red sky overhead was a sign of the end of the world.
If you live in a southern state like Florida, Texas, or even Hawaii, Murtagh says you’ll need a few other pieces in addition to a G-4 or G-5 storm to align yourself perfectly. These include the storm hitting the ground around 8 or 9pm (so you can actually see the lights), clear skies and a view away from the light pollution caused by cities and towns.
And before you go in search of the Northern Lights, check out the lunar cycle. A bright full moon can outshine nearby auroras, Murtagh explains.
However, more severe geomagnetic storms are less common. For example, a G-1 storm may occur 1,700 times per solar cycle (more on that later), or about 900 days in 11 years. A G-5 storm can only occur about four times during a solar cycle.
Luckily, we’re approaching the maximum phase of the solar cycle, Murtagh tells Nexstar. This puts us “in the middle of a trend reversal,” he explains, pointing out that experts assume that we will reach the peak of the solar cycle in 2024 or 2025.
“The [solar] The cycle ramps up faster, and when it ramps up faster, it’s usually larger,” Murtagh explains. “The bigger the cycle, the more outbreaks [on the Sun]the bottom line, the more likely we are to see the aurora.”
We could see powerful geomagnetic storms every month, he adds. While it can be difficult to say exactly when the US will have a chance to see the Aurora Borealis, NOAA offers Forecasts for one day and the next day for possible Northern Lights observations.
It is also important to note that while flares on the sun can result in a stunning nighttime spectacle, geomagnetic storms can present a challenge to some of our infrastructure.
As Steenburgh previously explained to NextarLight or moderate geomagnetic storms can cause small fluctuations in the power grid and affect satellite operations on spacecraft. Stronger storms can cause power outages, radio problems, and problems with navigation systems, including on airplanes. Luckily, the SWPC is able to communicate with the infrastructure officials to ensure everything continues to run smoothly and your Aurora viewing is uninterrupted.
“When you see these auroras, take a moment with us,” says Murtagh. “We’re going to be hopping, it’s going to be very busy and we’re doing everything we can to keep the infrastructure running so no one knows there’s a negative side to this beautiful aurora.”
Nexstar’s Alix Martichoux contributed to this report.