First-ever hyperspectral images of auroras on earth.
Source: Astrophysics and Astronomy.
A team of space-weather researchers have designed and built NORUSCA II, a camera that can simultaneously image different wavelengths or colours of light. The camera was tested at the Kjell Henriksen Observatory (KHO) in Svalbard, Norway and the first-ever hyperspectral images of auroras were produced.
Auroras are created when charged particles from the Sun interact with the Earth’s magnetic field. Auroras assist scientists to understand how Earth responds to solar storms. Current cameras that are used to capture these beautiful phenomena collect all the light into one image and cannot separate and analyse different parts of the visible spectrum. Before the use of the NORUSCA II hyperspectral camera, researchers studying auroras had to use a series of filters to block out some of the wavelengths, so they could study portions of the spectrum.
The NORUSCA II has advanced optics that let the camera to switch between its 41 separate optical bands over the course of a few microseconds, which is much faster than an ordinary camera. This allows specific bands of the aurora to be combined into one image. The new camera is particularly suited for spectroscopy, as specific atmospheric constituents can be detected by their unique wavelengths.
The spectral signatures from these auroras can reveal changes in atmospheric behaviour, including the ionisation of gases during auroras. Multispectral imaging will mean scientists can better classify auroras from background sky emissions.
The NORUSCA II was tested on a Coronal Mass Ejection (CME) which hit the Earth’s magnetic field on January 24, 2012, producing amazing auroras. In the clearest image yet, researchers could image the aurora through a layer of low attitude clouds, which had not been possible with earlier instruments.
The camera also revealed a faint wave pattern of unknown origin in the lower atmosphere, resembling ‘airglow’. Airglow is the natural emission of light by the Earth’s atmosphere and can be produced by a number of sources, including cosmic rays hitting the upper atmosphere and chemical reactions. As the airglow appears at the same time as the aurora, it seems to suggest a different source. If confirmed as an auroral-generated wave interaction with airglow, it would be a new phenomenon and the first time that airglow has been associated with auroras.
The image shows the aurora as a colour composite image from the NORUSCA II camera. Three bands were combined to make the image. Each band was assigned a different colour (red, green, and blue), to enhance the features of the aurora for analysis.
Source: Image credit: Optics Express.
That's all folks!
SoftwareZ used (If applicable, then this is in regards to “ remixed ” images. :lol:):
♫ d(｡◕‿◕｡)b ♪♪
PS: My words are my own, my actions are my own. Everything I wrote and did in this post are my own responsibility.
All I'm offering is: YAP! 😉