Geomagnetic storms brought the northern lights to much of the US this week, painting the sky with vibrant shades of green and pink.
The northern lights were sighted across a vast area of states, including Idaho, Iowa, Missouri, New Mexico, New York, Oklahoma, South Dakota, Tennessee, Texas, and Washington state. The northern lights were visible as far south as parts of Florida and Alabama, a relatively rare event that highlights the intensity of this week’s storms.
“Well, we had activity tonight — a lot of geomagnetic storm activity,” said Shawn Dahl, services coordinator at the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center, in a video on X.
A geomagnetic storm occurs when charged particles from the sun’s atmosphere interact with Earth’s magnetic field. In addition to creating dazzling color displays, these storms can disrupt technologies on Earth, from satellites and GPS to radio communications and the power grid.
The activity was the result of a phenomenon called coronal mass ejections (CMEs), massive explosions of plasma and magnetic field from the sun’s outer atmosphere that grow in size as they head toward Earth.
Two CMEs reached Earth on Tuesday, Dahl said.
The resulting storm reached G4 levels, the second highest on NOAA’s five-step scale, and created a magnetic field that was “not only eight times stronger than normal, but … also favorable for continued activity,” Dahl said in a later update.
“This was the most energetic and strongest of that activity out in space,” said Dahl. “It was traveling significantly faster than those other two, and we think this is going to pack an even bigger punch than what we’ve already experienced.”
The Space Weather Prediction Center says the aurora could become visible “over much of the northern half of the country, and possibly as far south as Alabama to Northern California”.
The Met Office, the UK’s national weather service, said the aurora could also be visible over parts of Britain on Wednesday night, though it will likely be obscured by cloud cover — as happened in Michigan on Tuesday.
Fortunately, Americans in northern states won’t have to wait long for another chance to catch a glimpse.
How to see (and photograph!) the northern lights
A dark location is essential for seeing the aurora, so it’s important to get away from light pollution if you want a good view of the northern lights. It will be easier to see between 10 p.m. and 2 a.m. local time, according to the NOAA.
It’s hard to predict the exact time and place of the northern lights, but you can sign up for different services that alert you when an aurora might be visible in your area. For example, a citizen science platform called Aurorasaurus allows users to report when and where they see an aurora, and provides estimates of how visible an aurora is in a given area.
Another option is an app called My Aurora Forecast & Alerts, available for download on iOS and Android devices. It’s a location-based app that provides viewing probability and forecasts.
Smartphone cameras are better at capturing the full spectrum of an aurora than our naked eyes, so be sure to head out with your phone to see a more complete spectrum of colors. If your phone’s camera has a night mode option, it’s best to turn it on when photographing the northern lights. You can also switch your phone’s camera to manual mode and adjust the exposure settings for the perfect photo.
Why we’re seeing more northern lights
Auroras have been occurring more frequently in the United States for some time now, and will continue for several months. This influx of shimmering colors is happening because the sun is reaching the peak of its 11-year cycle and thus its solar maximum. Solar maximum causes solar flares, and this increase in activity brings ions, or electrically charged particles, closer to Earth. This flow of particles is known as the solar wind.
As the solar winds approach Earth, the charged particles collide with gases in Earth’s atmosphere. When they collide, light is emitted. The light is emitted at various wavelengths, creating a colorful display across the night sky.
When the sun is at solar maximum, the number of solar flares increases, which explains why there are more auroras in the sky. Normally, this activity occurs only near the Arctic Circle, but since solar activity is strong now, viewing areas have expanded to other regions, like the Midwest.
Source: npr.org by Rachel Treisman, Mansee Khurana