Citizen Scientists Just Discovered A New Kind of Aurora

Citizen scientists and physicians have just discovered the 'dune' aurora in Finland, providing new knowledge about the Earth's upper atmosphere. You don't have to have a degree in science to discover new things about the Earth!

This article first appeared in Gizmodo.

To read about other discoveries, have a look at this article about how axolotls might have the answer to regeneration.

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via Newsweek

Amateur enthusiasts were gazing up at the beautiful green northern lights, or aurora borealis, when they noticed a pattern in the aurora that resembled the shape of sand dunes. The northern lights have many shapes, from spirals to arcs. But when the citizen scientists noticed something unusual, they took a photo and shared it to a Facebook page dedicated to the northern lights.
Minna Palmroth, a professor of computational space physics at the University of Helsinki, had asked citizen scientists to take photos of the northern lights for a book she is writing on the subject. When she was sent photos of the dune aurora, she was puzzled. She had never seen this shape of aurora before, and asked for more photos. These photos helped Palmroth and colleagues determine the altitude and spacing between the ripples of the aurora, leading them to conclude that the aurora was a never-before-seen phenomenon.
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via Gizmodo

Auroras occur when solar particles interact with gases in the ionosphere (the part of Earth's atmosphere that is ionized by solar and cosmic radiation). Nitrogen creates blue and purple auroras, while oxygen gives off red and green colors. The new dune auroras are thought to be glowing waves of oxygen atoms that are being struck with streams of electrons.
The dunes were located in the mesopause, which is a notoriously difficult area of the atmosphere to study (it's nicknamed the "ignorosphere"). It is too high for balloons and radars, but too low for satellites, making it almost impossible to reach. Researchers think that the dune auroras are forming because of a surge in oxygen density in the mesopause. This is called a "mesospheric bore" and it's a type of gravity wave disturbance that propagates through air, creating a rippling effect in clouds located in high altitudes.
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via Gizmodo

Palmroth explained to Gizmodo that northern lights happen more in places with dense oxygen, and less in places with scarce oxygen. The bore waves are causing oxygen levels to decrease and increase, creating the rippling "dune" appearance. Mystery solved.
It's an exciting day for scientists and citizen scientists alike, and Palmroth emphasised that the efforts of amateur skywatchers are always welcome. Have a look up tonight, you might discover something new!