Auroras – Delightful or Dangerous?

By Rachel Heimke

If Google Maps says you’re fifty feet away from where you are, it might be because the northern lights are disrupting the signal.

The aurora is a visual display that happens when highly charged particles from the sun interact with the Earth’s magnetic field. They bounce off each other and emit heat and light – the colored light we see as the aurora borealis.

The aurora doesn’t just manifest as a visual display, however. The stream of particles from the sun enters our atmosphere as solar wind. As it interacts with the Earth’s magnetic field, other things can happen, such as disrupting our telecommunication systems. 

Photo by Mike Degen

While we may see the aurora a few times a month while driving home from a hockey game or heading to the movies, some people at UAF look for it every night to study it.

Don Hampton researches the effects of the aurora on telecommunications. The ionosphere (a charged layer of Earth’s upper atmosphere) becomes denser when the aurora heats the atmosphere. It fills up with plasma waves, which are hot and highly charged.

“A plasma is basically a gas but is typically a very high temperature,” said Hampton. “A high enough temperature that … the atoms and molecules may lose an electron, becoming ions and electrons. You get a fair number of charged particles in there.” The charges induce electric and magnetic fields, which can reflect radio waves, so our communication system doesn’t work either. 

Hampton looks at the colors of the aurora to determine how the ionosphere will be affected. Each band of color carries a different amount of energy. Higher energy particles will emit shorter wavelengths like purple or blue, and lower energy particles will emit red. 

“If they’re separated by altitude, they’re separated by energy,” he said.

Hampton determines the energy level of the particles by looking at the ratio of colors. For example, the red band at the top of the aurora occurs at higher altitudes but has low energy. Arcs of green in the middle usually don’t affect telecommunications because they aren’t as high energy. But a high-energy band of pink at low latitudes can spell trouble. 

Hampton has been studying the aurora in Alaska since 2006. Now, he is the chief scientist at the Geophysical Institute’s Poker Flat Research Range. He uses cameras to look at the colors and motion of the aurora around the state. The cameras are all-sky cameras, meaning the lens can look at the entire sky from horizon to horizon. 

He wants to know how this changes the ionosphere to predict its effect on our satellite and ground communication systems. It can mess with our phones and our radio. It can also be a much more serious problem. 

In 1989, a geomagnetic storm, or disturbance of our magnetic field by a strong solar wind, wreaked havoc on ground power systems. Quebec experienced a nine-hour power outage. Communications failed as radio signals were jammed, and satellites lost communication to Earth. Another storm later that year caused the Toronto Stock Exchange to stop all trading for a day.

The sun works on an eleven-year cycle. 2024 is toward the end of that cycle, meaning that solar activity is high. A solar maximum means more extreme auroral events can occur in the next few months.

When auroras heat the atmosphere, the gas expands. This can extend our atmosphere’s reach around the earth as the gasses become thinner and extend further outward around our planet. For low-earth orbiting satellites, this becomes a problem. Their communication won’t work either, and they may change course slightly. An object moving at five miles per second might end up somewhere it’s not supposed to be. Collisions with space debris or other satellites become more likely in these conditions.

Another side of auroral research looks at which auroras are most problematic. Doğacan Ӧztürk researches what conditions lead to different types of aurora. She uses AI and machine learning to sort through large datasets and recognize patterns in auroral shapes.

Ӧztürk is trying to predict what types of aurora will appear on a particular night. Different types have different impacts on our ionosphere and, therefore, our telecommunications. We typically see arc aurora – the large arcs of color that remain relatively stable. These are low-energy auroras. Another type of aurora is the black aurora. This appears as dark patches in bright colors and acts as a reverse aurora. 

“Instead of particles coming down, they're going up, like a vacuum cleaner,” she said.

Discrete auroras are high-energy auroras that heat the atmosphere. When we see the aurora dance, it can typically be classified as discrete. Heating the atmosphere can affect satellite communication.

“Recognizing the patterns in these shapes of the aurora helps researchers predict when substorms (explosions of auroral activity) will occur,” Ӧztürk wrote in an email.

Knowing when auroral activity may increase and storms will happen will help people prepare for an emergency. Hopefully, having a small heads-up can prevent something like the Quebec blackout from happening again. 

“It's amazing to be in these kinds of locations where you can study the aurora because it’s directly like a window to space,” Ӧztürk said.