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Amateur astronomers discover a new form of Northern Lights that resemble SAND DUNES caused by waves of oxygen flowing through a stream of solar particles
By RYAN MORRISON FOR MAILONLINE
PUBLISHED: 04:00 GMT, 29 January 2020 | UPDATED: 04:03 GMT, 29 January 2020
Amateur astronomers have discovered a new form of Northern Lights that resemble sand dunes, caused by waves of oxygen flowing through a stream of solar particles.
The evenly patterned, green-tinged light show stretches for more than 30 miles and is found more than 60 miles up in the mesosphere.
They were identified by chance after space physicist Minna Palmroth from the University of Helsinki asked aurora watchers to send her photos for a book.
The hobbyist highlighted images of a particular aurora that didn’t seem to fit any known types – they dubbed them ‘auroral dunes’.
Professor Minna Palmroth said they were likely formed within the mesosphere and present an exciting opportunity to ‘investigate conditions in the upper atmosphere’.
The book was born out of Palmroth’s cooperation with enthusiasts and the answers she provided to questions about the physics of the phenomenon.
‘Each auroral form is like a fingerprint, typical only of a certain phenomenon in the auroral zone,’ said Professor Palmroth.
Just days after the book was published, the hobbyists saw the unusual form again and immediately informed the professor.
‘One of the most memorable moments of our research collaboration was when the phenomenon appeared at that specific time and we were able to examine it in real time’, says Northern Lights and astronomy hobbyist Matti Helin.
The phenomenon was photographed at the same time in both Laitila and Ruovesi, southwest Finland, with the same detail observed in both images.
Maxime Grandin, a postdoctoral researcher in Palmroth’s team, identified stars behind the emission and determined the azimuths and elevations of the stars with the help of the astronomy software program Stellarium.
This made it possible to use the stars as points of reference when calculating the altitude and extent of the auroral phenomenon.
The team spotted a total of seven similar ‘auroral dune’ events where a camera recorded the same even pattern of waves.
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