Experts predicted we’d see the best northern lights in two decades this year during the solar maximum, when the sun reaches its peak activity. But our closest star is far exceeding expectations—solar flares in mid-May triggered aurora borealis that NASA says is “possibly one of the strongest displays…on record in the past 500 years.”
There’s only more to come.
The sunspot that in May caused a level G5 geomagnetic storm, the rarest and strongest that exists, is back to it—releasing more solar flares and causing temporary shortwave radio blackoutsacross East Asia.
But will it produce another round of incredible auroras seen at latitudes much farther south than usual? To trigger another storm on Earth, the flares would have to create a coronal mass ejection (CME). The best odds of one hitting our planet will happen again on June 4 to 6, one solar rotation since the mid-May storm.
Solar storms—eruptions that propel electrically charged particles at high speeds away from the sun—don’t just produce auroras, though. They also have the potential to cause electrical grid collapse, blackouts, and damage transformers. Radios could be out for hours, and satellite navigation could be degraded for days.
Experts weigh in on the significance of this year’s solar activity, how best to see auroras, and what to know about how a solar storm can affect life on Earth.
How to see the northern lights during the solar maximum
This year, the sun is reaching the peak (called the “solar maximum”) of its roughly 11-year cycle, in which solar activity will be greatest. But this maximum has even more excitement around it than usual because the last one in 2014 was the weakest in a century, says Mark Miesch, a research scientist at NOAA’s Space Weather Prediction Center in Boulder, Colorado.
The northern lights appear in a region around the earth’s magnetic pole, called the “auroral oval” or “auroral zone”, explains Don Hampton, research associate professor at the Geophysical Institute of the University of Alaska Fairbanks. But that region shifts and fluctuates all the time, depending on the strength of solar wind, a stream of charged particles from the sun’s atmosphere that can be strengthened by storms. During the solar maximum, experts expect that episodes when the auroral zone grows and is more active will happen more frequently.
“When there’s more energy, [the auroral zone] gets thicker and expands further south,” says Hampton. “I don’t think it is too wild a prediction to say that people in the midwest and maybe even lower midwest (40th parallel) will have a good chance to see aurora once or twice during this solar cycle, but there are no guarantees,” he says. In the U.S., the 40th parallel runs through Provo, Utah; Boulder, Colorado; north Indianapolis; and Columbus, Ohio.
Aurora forecasting apps like NOAA’s Space Weather Prediction Center, Aurora Alerts, and My Aurora Forecast & Alerts can help chasers predict when it will be best to see the northern lights as well as how far south the auroral oval will extend after solar activity. On average, auroras are more frequent around the March and October equinoxes, says Magnus Wik, a space weather scientist at the Swedish Institute of Space Physics.
There’s more to consider when it comes to timing and location—cloudy or light-polluted skies will make aurora spotting difficult or impossible.
To escape manmade light pollution, consider searching DarkSky.org for certified international dark sky places around the world.
The direction you look matters, too, depending on your location related to the auroral oval. “In Alaska, if we get a big solar storm, we look overhead or south,” Hampton says. “In the Midwest, find a field and look north and see what you can see.”
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Not all aurora viewing is created equal, cautions Miesch.
“On the rare occasions when you can see it well in the contiguous U.S., it is usually a faint red glow on the horizon—nowhere near as dramatic as in pictures and movies,” he says.
What are solar flares and solar storms?
The sun’s current cycle, Solar Cycle 25, started in December 2019. Activity on our closest star is expected to peak earlier and stronger than NOAA previously predicted at the start of the cycle.
Solar flares, coronal mass ejections and sunspots are just some of the solar events that are expected to increase in frequency and strength in 2024, says Wik.
Sunspots are darker, cooler areas on the sun’s surface where magnetic force is significantly higher than elsewhere on the sun. Hampton says this cycle has already seen more sunspots than the past few solar cycles. Both solar flaresand coronal mass ejections (CMEs) often happen near these areas and both expel energy into space.
“Solar maximum means more storms, and during storms northern lights occur more often, are more intense, last longer and can extend to lower latitudes than usual,” says Slava Merkin, space physicist and director of the Center for Geospace Storms at the Johns Hopkins Applied Physics Laboratory.
Auroras are caused by the interaction of the solar wind (a stream of hot magnetized gas called plasma) with the magnetosphere (the region of space around Earth in which our planet’s magnetic field is dominant), Miesch says. There are two kinds of plasma emissions from the Sun that cause auroras: CMEs and high speed solar wind streams that can also cause weaker geomagnetic storms.
How do solar storms affect the Earth?
While many solar storms send gusts of solar wind in other directions, those that hit the Earth can compress and distort our magnetosphere, the protective magnetic bubble surrounding the planet, says Miesch.
Conditions in our outer atmosphere, including the magnetosphere, impact technology on Earth in many ways, says NOAA's Space Weather Prediction Center Program coordinator, Bill Murtagh, including disrupting GPS functions and interfering with satellites in low orbit.
In 1967, one powerful solar flare almost triggered nuclear war, when the U.S. military had less than 30 minutes to determine whether a radio blackout was due to Soviet jamming signals or a natural event.
With current solar activity levels higher than in the past 20 years and increasing into 2024, it means more storms to learn from, says Miesch.
“The more we observe these phenomena the better we understand them and the better we understand them the better we can predict them.”
This story was originally published December 2023 and was updated May 2024.
