OpEx   auroras   image3 Scientists take first hyperspectral photos of Earths auroras

The first ever hyperspectral images of Earth's auroras, bizarre and beautiful lights in the sky, have been captured with a new purpose-built camera.

The first ever hyperspectral images of Earth's auroras, bizarre and beautiful lights in the sky, have been captured with a new purpose-built camera.

 
Researchers at the University Centre in Svalbard (UNIS), Norway developed the NORUSCA II camera, which can simultaneously image multiple spectral bands of light, allowing for some new discoveries when it comes to the so-called “Northern Lights.”
 
Tests at the Kjell Henriksen Observatory in Svalbard produced the first hyperspectral images, which pick up and separate light over different bands.
 
“A standard filter wheel camera that typically uses six interference filters will not be able to spin the wheel fast enough compared to the NORUSCA II camera,” said Fred Sigernes of UNIS. “This makes the new hyperspectral capability particularly useful for spectroscopy, because it can detect specific atmospheric constituents by their unique fingerprint, or wavelengths, in the light they emit.”
 
OpEx   auroras   image3 Scientists take first hyperspectral photos of Earths auroras
An aurora appearing in the night sky at the Kjell Henriksen Observatory in Svalbard, Norway. Taken November 2010. Credit: Njaal Gulbarndsen.
 
The technology also helped the scientists uncover a previously unknown atmospheric phenomenon and could pave the way for even more discoveries in the future. 
 
On 24 January a major solar flare called a Coronal Mass Ejection (CME) hit the Earth and caused widespread auroras, and tests conducted then found a faint wave pattern of unknown origin in the lower atmosphere. It resembled the natural emission of light by the Earth's atmosphere called “airglow,” but this has never previously been associated with auroras, making it an entirely new phenomenon.
 
“Our new all-sky camera opens up new frontiers of discovery and will help in the detection of auroras and the understanding of how our Sun impacts the atmosphere here on Earth,” said Sigernes. “Additional development and commissioning will also hopefully verify our intriguing first results.”
 
The findings were published today in a paper in Volume 20, Issue 25 of the Optical Society's journal Optics Express.
 
OpEx   auroras   fig1 Scientists take first hyperspectral photos of Earths auroras
The aurora as seen as a color composite image from the NORUSCA II camera. Three bands were combined to make the image. Each band was assigned a different color  red, green, and blue – to enhance the features of the aurora for analysis. Credit: Optics Express.
 
OpEx   auroras   fig2arrows Scientists take first hyperspectral photos of Earths auroras
The red arrow points to the unidentified low-intensity wave pattern, which the researchers suspect is an auroral-generated wave interaction with airglow. For contrast, the blue arrow points to the faint emission of the Milky Way. Credit: Optics Express.
 
OpEx   auroras   image4 small Scientists take first hyperspectral photos of Earths auroras
Students perform measurements of the aurora in front of the Kjell Henriksen Observatory. Svalbard, Norway, November 2010. Credit: Njaal Gulbarndsen.