The sun is now in its solar maximum, meaning more aurora activity
This year has given stargazers plenty of opportunities to catch the colorful auroras of the northern lights flicker across the night sky, and that's expected to continue as the sun is now in its solar maximum – the peak of its 11-year solar cycle.
Representatives from NASA, the National Oceanographic and Atmospheric Administration (NOAA) and the international Solar Cycle Prediction Panel made the announcement at a news conference Tuesday.
"During solar maximum, the number of sunspots, and therefore, the amount of solar activity, increases,” said Jamie Favors, director of NASA's Space Weather Program. “This increase in activity provides an exciting opportunity to learn about our closest star ? but also causes real effects at Earth and throughout our solar system.”
This peak of activity is expected to last another year, according to NASA.
What is Solar Cycle 25?
The sun, and the intense magnetic activity it generates that causes the northern lights, waxes and wanes on an 11-year-long solar cycle. The peak of activity – the solar maximum – occurs when the sun's north and south magnetic poles flip. As the solar cycle reaches its zenith, solar flares, solar system's largest explosive events, increase, which causes phenomena such as May's solar storm, the largest observed by NASA in decades.
Scientists have observed the sun's solar cycles since 1755, and according to new observations, the sun has already been at its solar maximum for a couple of years.
“This announcement doesn’t mean that this is the peak of solar activity we’ll see this solar cycle,” Elsayed Talaat, director of space weather operations at NOAA, said Tuesday. “While the sun has reached the solar maximum period, the month that solar activity peaks on the sun will not be identified for months or years.”
More: Peak northern lights activity coming soon: What to know as sun reaches solar maximum
Solar flares emit radiation, mostly in the form of ultraviolet light and X-rays, that can hurtle toward Earth at the speed of light. Some of these flares can be accompanied by coronal mass ejections, or clouds of plasma and charged particles, that emerge from the sun's outermost atmosphere, the corona.
These ejections can collide with Earth’s magnetosphere, the barrier protecting humanity from the harshest impacts of space weather, to produce geomagnetic storms.
Geomagnetic storms can spark northern lights
That may sound scary, and because of the elevated risk for things like disrupted satellite signals, radio communications, the internet and electrical power grids, it could be.
But the heightened possibility for more geomagnetic storms also may mean more impressive northern lights displays.
In May, a powerful geomagnetic storm was responsible for some reports of power grid irregularities and interference with GPS signals – even farming equipment. On the bright side, it did also unleash spectacular views of the northern lights in parts of the country where auroras are not often visible.
The celestial show came after NOAA issued a storm watch for the first time in 19 years for a geomagnetic storm classified as a G4 – a single level away from being the most severe solar storm possible. Amid the solar activity, the sun even emitted an explosive burst of radiation that became the largest solar flare detected since 2017, according to the NOAA.
The phenomenon, which has made several recent appearances across the U.S., was also notably visible again in August during the Perseids, considered among astronomers the best meteor shower of the year.
What causes auroras?
The auroras are a natural light display in Earth's sky that are famously best seen in high-latitude regions of the northern and southern hemispheres.
The phenomenon is caused when electrically charged particles from space enter Earth's atmosphere and collide with molecules and gasses like oxygen and nitrogen, causing the atmospheric particles to gain energy. To return to their normal state, the particles release that energy in the form of light, according to the University of Alaska at Fairbanks Geophysical Institute website, which tracks the phenomenon.
As auroras form, Earth's magnetic field redirects the particles toward the poles through a process that produces a stunning display of rays, spirals and flickers that has fascinated humans for millennia. Whether hues of green, red, blue and even pink dance about in the sky depends on the altitude of the collisions, as well as the composition and density of the atmosphere at the time.
Solar activity to continue in 2025
“Solar Cycle 25 sunspot activity has slightly exceeded expectations,” said Lisa Upton, co-chair of the Solar Cycle Prediction Panel. “However, despite seeing a few large storms, they aren’t larger than what we might expect during the maximum phase of the cycle.”
Predicted just when and where one might see the northern lights remains difficult, but NOAA does maintain an aurora dashboard that should help skygazers track the phenomenon.
Max Hauptman is a Trending Reporter for USA TODAY. He can be reached at [email protected].
Eric Lagatta covers breaking and trending news for USA TODAY. Reach him at [email protected]
This article originally appeared on USA TODAY: NASA announces that the sun is now in its solar maximum