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Power Cables' UV Flashes Apparently Frighten Animals
Rambo Tribble writes "Ultraviolet light flashes, or "corona", may be scaring animals and altering behavior. An international scientific team, first studying behavioral anomalies in reindeer near power lines, have found that sporadic flashes of UV from the lines are probably responsible. As most mammals can see into the UV spectrum, this has broad implications for the disruption of animal behavior. From the BBC article: "Since, as the researchers added, coronas 'happen on all power lines everywhere,' the avoidance of the flashes could be having a global impact on wildlife.""
Here is what the corona discharges look like: https://www.youtube.com/watch?...
Pretty amazing, really.
Thermal emissions from body heat are a fair ways into the IR range, around 8000-15000nm. For reference, human vision peters out around 700nm. I believe it's only possible to detect that with specialized sensory organs, such as pit viper's eponymous thermal pits.
upon the advice of my lawyer, i have no sig at this time
Thermal IR (the wavelengths emitted by things around body temperature) is really low-energy. It's hard to focus, and hard to detect, especially with a detector that's already in the same temperature range. Pit vipers, vampire bats and some other animals do it, but the mechanism's fundamentally different from normal vision, and doesn't provide much in the way of an actual focused image. (The pit viper's pit is sort of like a pinhole camera with a really big pinhole.)
Near-IR, the kind of thing that cheap digital security cameras can see, is higher-energy. It can be emitted thermally, but you've got to get pretty hot (hundreds of degrees) to produce significant amounts. Go a little hotter, and you can produce visible light ("red-hot", "white-hot", etc.).
Even near-IR is hard to pick up with a chemical process, though, the way retinal cells pick up visible light. I'm not aware of any animals that can see significantly further than us into the near-IR -- okay, a bit of Googling turned up one fish that can do it.
50/60 Hz is pretty much DC anyway
LOL, clearly either a digital logic or RF engineer.
Tell ya what, if you're that confident, then take an aluminum crochet needle in each hand and jam them each in the +/– terminals of a 12 volt DC power supply, then in the line/neutral sockets of a variac output tuned down to 12V, and tell us again that 60 Hz is 'pretty much DC anyway.'
(Spoiler: one will be fatal and the other not.)
And then see if you can figure out why Westinghouse engineers chose the frequency at which electrical impulses best travel along human nerves as the standard power transmission frequency...
I can see the fnords!
The UV suff in laundry detergents does not reflect UV light. IT flouresces in the visible spectrum (blueish) when illuminated by UV light, thus actually making the clothes brighter (as long as UV radiation is present).