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Spending a night staring at aurora borealis, or the northern lights, remains a bucket list tick for millions around the world.

Despite all of the immense technological and scientific advancements in recent times, the exact cause of this incredible spectacle has never proven.

Until now, that is.

Earth’s greatest light show (aurora australis, or the southern lights, is also spectacular, but usually less visible) can now be explained, thanks to a group of physicists from the University of Iowa.

CNN reports:

…the “most brilliant auroras are produced by powerful electromagnetic waves during geomagnetic storms,” according to a newly released study…

The study shows that these phenomena, also known as Alfven waves, accelerate electrons toward Earth, causing the particles to produce the light show we know as the northern lights…

Image: Austin Montelius, College of Liberal Arts and Sciences, University of Iowa

“Measurements revealed this small population of electrons undergoes ‘resonant acceleration’ by the Alfven wave’s electric field, similar to a surfer catching a wave and being continually accelerated as the surfer moves along with the wave,” said Greg Howes, associate professor in the Department of Physics and Astronomy at the University of Iowa and co-author of the study.

We never said it was a simple explanation.

Props to Russian physicist Lev Landau, who first proposed the theory of electrons “surfing” on the electric field back in 1946.

75 years later, and he has been vindicated.

For the first time, scientists have now been able to simulate the aurora in a lab setting:

Scientists used a 20-meter-long chamber to recreate Earth’s magnetic field using the powerful magnetic field coils on UCLA’s LPD. Inside the chamber, scientists generated a plasma similar to what exists in space near the Earth.

“Using a specially designed antenna, we launched Alfven waves down the machine, much like shaking a garden hose up and down quickly, and watching the wave travel along the hose,” said Howes.

As they began to experience the electrons “surfing” along the wave, they used another specialized instrument to measure how those electrons were gaining energy from the wave.

Whilst they failed to recreate the famous colours seen in the sky, they proved that electrons surfing on Alfven waves can accelerate the electrons that cause the aurora.

Well done to the team behind the discovery, and well done to anybody who has managed to follow along thus far.

You’ve earned a look at a particularly stunning northern lights display, filmed in Norway back in 2012:

[source:cnn]