First-Ever Hyperspectral Images of Earth's Auroras: New Camera

New Camera Provides Tantalizing Clues of New Atmospheric Phenomenon.

Looks like one out of an old marble collection.

Hoping to expand our understanding of auroras and other fleeting atmospheric events, a team of space-weather researchers designed and built NORUSCA II, a new camera with unprecedented capabilities that can simultaneously image multiple spectral bands, in essence different wavelengths or colors, of light. The camera was tested at the Kjell Henriksen Observatory (KHO) in Svalbard, Norway, where it produced the first-ever hyperspectral images of auroras -- commonly referred to as "the Northern (or Southern) Lights" -- and may already have revealed a previously unknown atmospheric phenomenon.

source

The new NORUSCA II hyperspectral camera achieves the same result without any moving parts, using its advanced optics to switch among all of its 41 separate optical bands in a matter of microseconds, orders of magnitude faster than an ordinary camera. This opens up new possibilities for discovery by combining specific bands of the same ethereal phenomenon into one image, revealing previously hidden details.

In a nutshell Auroras are created when charged particles from the Sun penetrate Earth's magnetic field.

Current cameras are simply light buckets,meaning they collect all the light together into one image, and lack the ability to separately capture and analyze multiple slivers of the visible spectrum. So to study auroras by looking at specific bands or a small portion of the spectrum they would have to use a series of filters to block out the unwanted wavelengths.

"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,"

A New Phenomenon

On Jan. 24, 2012, during the inaugural research campaign of NORUSCA II, a major solar flare jettisoned a burst of high-energy particles known as a Coronal Mass Ejection (CME). The CME eventually slammed into Earth's magnetic field, producing magnificent auroras and a chance to fully test the new camera. The researchers were able to image the aurora in unprecedented clarity through a layer of low altitude clouds, which would have thwarted earlier-generation instruments (see Image 1). The camera also revealed something unexpected -- a very faint wave pattern of unknown origin in the lower atmosphere (see Image 2). The wave pattern resembles "airglow" -- the natural emission of light by Earth's atmosphere. Airglow can be produced by a variety of known sources, including cosmic rays striking the upper atmosphere and chemical reactions. Its concurrent appearance with the aurora suggests that it may also be caused by a previously unrecognized source.

The new 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.

About that "new" phenomenon:

Just after the auroral display close to ~17 UT, the rapid playback of the animation reveals a one hour dynamic weak intensity wave pattern of unknown origin. It resembles in shape and signature airglow and gravity wave interaction down in the mesosphere (80-90 km). See Fig. 7. It could just be a coincident or one could speculate that it is formed by auroral generated waves propagating downwards. Further studies are needed to reach a conclusion on this issue.

The original article is available here:
www.opticsinfobase.org...

An animation of the images here:
www.opticsinfobase.org...

Originally posted by Phage
About that "new" phenomenon:

Just after the auroral display close to ~17 UT, the rapid playback of the animation reveals a one hour dynamic weak intensity wave pattern of unknown origin. It resembles in shape and signature airglow and gravity wave interaction down in the mesosphere (80-90 km). See Fig. 7. It could just be a coincident or one could speculate that it is formed by auroral generated waves propagating downwards. Further studies are needed to reach a conclusion on this issue.

Looks like the animation is from the full sky sequence shot in Jan as mentioned above, fascinating.

Here's the observatory, burr. I could see myself doing a stint there.

reply to post by Lonewulph

Looks like the animation is from the full sky sequence shot in Jan as mentioned above, fascinating.

Yes. The phenomenon of gravity waves appearing in airglow is not new though. What may be is finding a correlation between the aurora and the effect.

reply to post by Phage


Nice,
I wonder if it simply propagating downwards? Have you seen a conclusive on it anywhere yet?

(down into the mesosphere...I wonder if there are any environmental concerns there?)

reply to post by Lonewulph

The indications for most gravity waves is that the propagation is upward, from the troposphere and stratosphere to the mesosphere and ionosphere. Downward propagation (from extremely low density to high density) is somewhat problematic. I suppose that is why the idea that this observation may have been related to the auroral display is of interest.

Try this for interesting:
Propagation of tsunami-driven gravity waves into the thermosphere and ionosphere

reply to post by Phage


10 hours of sleep over the last 3 days..so i am a little punchy. But to clarify you are refering to the meteorlogical phenomenon when you say "gravity waves" (which tends to be more about air pressure, etc), not true "gravitational waves", correct?