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What creates the northern lights?

Scientists may have figured out what causes the northern lights

The northern lights, or aurora borealis, in Bifrost, Western Iceland.
The northern lights, or aurora borealis, appear in the sky over Bifrost, Western Iceland, on March 1, 2017.
Rene Rossignaud, Associated Press

Why do the northern lights happen? Why do the blue, green and violet lights appear in the sky and ripple in a moment of beauty? Well, researchers may have finally figured it out.

Why do northern lights happen?

New research suggests that the natural northern lights phenomena happen when there are disturbances on the sun that pull on Earth’s magnetic field, according to NPR.

  • This then “creates cosmic undulations known as Alfvén waves that launch electrons at high speeds into Earth’s atmosphere where they create the aurora,” according to NPR.

The researchers — physicists from the University of Iowa — found that “most brilliant auroras are produced by powerful electromagnetic waves during geomagnetic storms,” according to the new study.

  • Essentially, the Alfvén waves “accelerate electrons toward Earth, causing the particles to produce the light show we know as the northern lights,” according to CNN.

Gregory Howes, associate professor of physics and astronomy at the University of Iowa, explained it a little more simply to NPR.

  • “It was sort of theorized that that’s where the energy exchange is occurring,” Howes told NPR. “But no one had ever come up with a definitive demonstration that the Alfvén waves actually accelerate these electrons under the appropriate conditions that you have in space above the aurora.”

The researchers published new findings in an article in the journal Nature Communications.

What’s next?

Researchers told CNN that there’s still a long way to go for them to understand how to produce the northern lights and to understand how strong the northern lights will be when they appear.

  • “Predicting how strong a particular geomagnetic storm will be, based on observations of the sun and measurements from spacecraft between the Earth and the sun, remains an unsolved challenge,” Howes told CNN.