Astronomers from the Kjell Henriksen Observatory at Svalbard have released the first images from the NORUSCA II camera, showing the Northern Lights captured across 41 spectral bands. NORUSCA II is designed to switch between all of its optical bands “in a matter of microseconds”, explains this announcement. A standard camera with …
Auroras are often magnificent, but this adds a whole new dimension (38 actually, from 3D RGB to 41D hyperspectral)!
I wonder if the airglow wave pattern is in some way similar to ionospheric waves seen by the LOFAR antennae. Those seem to occur at higher altitude, but I wonder if similar mechanisms trigger them (or that there is some coupling between ionospheric waves and the low altitude wave pattern seen here).
Unless those were taken with a traditional camera (ie. film) I wouldn't discount them simply being artifacts of the size and spacing in a CCD. They look a lot like Moiré lines.
If that is the case, then surely you'd expect to see that pattern in the same place on multiple exposures? I'd be surprised if kit like that wasn't thoroughly tested and calibrated before actual use, which would show up any defects in the CCD/CMOS long before actual research is done.
Not every object ever made uses the traditional Apple beta testing method of 'Let the consumers find the bugs, then we release the new, fixed version' :O)
Moire patterns (properly aliasing artefacts) occur when a semi-periodic pattern below the limit of resolution of the CCD occurs in the image, not in random noise patterns. Thus the signal needs some semi-periodic component to get these artefacts. I have seen hundreds of astronomical images taken below the resolution limit of the optics, and have never yet seen Moire-like aliasing artefacts.
I stand corrected. :)
"NORUSCA II is designed to switch between all of its optical bands “in a matter of microseconds”, explains this announcement. A standard camera with six machine-driven filters wouldn’t be able to keep up."
... and so we have here cameras showing the same thing in different wavelengths 'microseconds apart'?
No, try 2 1/4 hours! Can it actually be shown that the two observations have any relationship? Two observations, different wavelengths, different structures at different times ...
It's certainly not a justification for building an uber-fast-switching camera!
I hope the boffins in Svalbard are prepared for Dust, Spectres and armoured bears.