While inspecting a three-year-old footage of the Arctic sky, a NASA intern discovered a new type of aurora.
A video from Norway offers a glimpse of the aurora twisting in unusual patterns. Usually, aurorae dance across the sky when lots of high-energy particles flood over the Earth. This phenomenon is called as solar winds and is represented by the heightened activity of the Sun. But in this case, the Sun did not show any eruptions.
Digging deeper, Jennifer Briggs, a physics student at Pepperdine University in California, Unites States could connect the unusual aurora to a sudden retreat in Earth’s magnetic field; probably the first time that scientists saw an aurora caused solely by a compression of the magnetic field of the Earth. Although researchers are not quite sure why this magnetic crunch happened, they think it might have been a solar storm in the region where Earth’s magnetic field meets the particles of the Sun.
While the cause still remains unknown, the mysterious compression produced a slew of stunning, twisting aurorae in the picture below, which was observed from an island in Norway.
The bright, colourful lights of the aurora come from collisions between electrically charged particles from the sun and gases in the Earth’s atmosphere, like nitrogen and oxygen. Earth’s magnetic field usually deflect these particles, but the field is weaker at the planet’s poles. So, some particles sneak through producing the aurora borealis near the north pole.
As per Briggs, a huge compression in the Earth’s magnetosphere was detected on the day of this particular aurora, right at the moment the lights began spiraling. Within one minute and 45 seconds, the edge of the magnetosphere passed the NASA satellite that detected it and moved towards the Earth’s surface, shifting by about 25,000 kilometers.
“You can imagine someone punching Earth’s magnetic field,” Briggs said in a press conference. This motion is something that we’ve never seen before. “This eastward and then westward and then spiraling motion is not something that we’ve ever seen, not something we currently understand,” she added.