Capturing a multicolored, all-sky image of the auroras that decorate Earth’s polar skies is now possible.
Normally, studying these shimmering phenomena means taking multiple images of an aurora, using different filters that block or image different wavelengths. Now, a camera with tunable liquid crystal filters can capture many colors at once, a team of space-weather researchers reports Nov. 29 in Optics Express.
Called NORUSCA II, the camera also takes pictures of the entire sky. Scientists are hoping that such precision aurora-imaging will help them better understand and classify the celestial light shows.
The team tested the sky-gazing camera at the Kjell Henriksen Observatory in Svalbard, Norway, during the auroral season of 2011 and 2012. On Jan. 24, 2012, an enormous solar flare flung a blob of charged particles in Earth’s direction. The skies over Svalbard lit up as the particles struck Earth’s atmosphere, producing a bright green aurora and intense geomagnetic storm.
Charged particles colliding with different gases in Earth’s atmosphere produce the multicolored auroras. For example, oxygen atoms can glow green or red, depending on their altitude. Hydrogen and helium high in the ionosphere can produce shimmering blue or purple. Nitrogen? Red, violet, or blue.
The new camera captured these swirling lights using many different wavelength channels; individual frames from the Jan. 24 event have been stitched together in the video above. And the camera is sensitive enough to see daytime auroras, like the reddish lights flickering across the sky on Dec. 29, 2011 (video below).
Videos: Optics Express, Vol. 20, Issue 25.
New Camera Snaps All-Sky Auroras in Full Color
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New Camera Snaps All-Sky Auroras in Full Color
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New Camera Snaps All-Sky Auroras in Full Color
