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Turn-key auroral imagers

Posted: Thu Dec 02, 2004 4:58 pm
by RJN
Many people have noticed fisheye nighttime imagers are also being used for the detection of aurora. One such network of auroral images occurs with the NASA-funded THEMIS (Time History of Events and Macroscale Interactions During Substorms) project. Their main web page is here: http://ds9.ssl.berkeley.edu/themis/mission_mystery.html

Noah Brosch has pointed out to me recently a new company that makes fisheye cameras, primarily, it seems, for imaging aurora. This company is KEO and their web site is here: http://keoscientific.com/index.html

Could these imagers be used for astronomy?

On the positive side, these camera systems appear to be controlable by computers, even running Linux. The CCD does appear to be cooled.

On the negative side, I just don't know how weather proof they are. The literature only discusses using these systems with a video frame grabber at many images per second. They might be usable for minutes-long integrations, but I was not able to find this. They don't say the throughput of their lens. They indicate that their CCDs have 512x512 pixels, which itself pushes more sky brightness into pixels than current and planned future CONCAMs. Clearly, they have little or no software for analyzing stars like we do. They do not give a price for any full system.

I think these systems might be useful for low-end observatory sky cameras, but not for cutting-edge astronomy. Still, many observatories might only want the low end equipment as a "dumb" night sky cloud monitor.

Anyone have thoughts on these? One day, will future NSL hardware be bought off-the-shelf from companies like Keo Scientific?

- RJN

NSL cameras vs. auroral imagers

Posted: Fri Dec 03, 2004 8:48 pm
by nbrosch
Bob, the auroral imagers are designed to image spectral features. The aurora shows up in forbidden emission lines and the cameras used for imaging it must have narrow-band filters. They also use intensified video cameras, because sometimes there are fast variations in the brightness, color. or position of the aurora. This is because auroras are connected with geomagnetic phenomena.

While aurora cameras also use fisheye lenses, they are not interested very much in stellar images, except as calibrators.

The scientists studying it are mostly located in nordic countries, Canada, Sweden, Norway, and Finland.

Cheers,
Noah Brosch