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Saw some interesting images captured by the Gemini North web cams this evening; military training occurring in and over the Pohakuloa training area:
Brief video towards the wet capturing UKIRT and a flare -
https://goo.gl/li99QA
Brief video towards the north capturing one of the Kecks, the IRTF and military jets flying over Pohakuloa -
https://goo.gl/YK6BS5
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I saw some Military activity Hamakua Mauka tonight, also perhaps a medivac into Waimea???? Whatever it was, was a turboprop and had it's landing lights on by Pa'auilo. Do aircraft who leave their landing lights on longer than usual bother you guys on the Observatories? I'd imagine so! Groovy Images, as always!!!
AKpilot
We're all here, because we're not all there!
We're all here, because we're not all there!
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Landing lights are no problem at all, and even if they were, I can't see the observatories complaining about them as they are used for safety reasons (see and be seen). In any case, they are insignificant compared to light from other sources.
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You screwed up TomK. I can clearly see you firing your laser cannons in the second video! Probably keeping the UFOs from returning home to Pahoa...
So the telescopes are fairly 'selective' when it comes to local light sources like a plane flying over? Does light more than a degree from your target even make it into the optics? Do you guys ever have issues with green lasers, like the commercial airline flights that get dazzled? Thanks!
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randomq - yes, well spotted! Still, the telescopes fought off a major attack from the space aliens last night, so we remain safe.
As to your excellent question, the answer is quite involved but will keep it brief. Yes, individual lights can cause problems. If you observe close to a bright light source, be it a star or the moon, that light can be reflected into the optics. When UKIRT is in wide-field mode, for instance, we stay more than 20 degrees from the moon otherwise we get reflections and "moon ghosts" in our images. As for lights from aircraft, they are rarely a problem as they are not that bright and are temporary. There are times we do capture contrails in our wide-field images (as well as satellites), but it's not a huge problem. The other thing to consider with aircraft lights is that most airplanes here are flying quite low in the vicinity of MK as they are landing or taking off. The telescopes tend not to observe lower than 30 degrees above the horizon, so those lights are mostly a non-issue.
As for light pollution in general, it's not so much individual lights that cause problems, but it's the general brightness of the sky. So a large town or city can make the sky brightness high enough that faint objects are almost impossible to see. This also happens with moonlight, but of course, the moon isn't always up.
I hope that's a little help.
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Humm....wonder what a satellite looks like in a wide-field. I still Satellite hunt, my favorite are the old Iridiums.......they have great flares!
AKpilot
We're all here, because we're not all there!
We're all here, because we're not all there!
