blue lightning today

  sunnystaines 21:39 28 Jul 14
Locked

stuck on M3 today as a result of the pileup and was watching the fork lightning a spectacular show. Then suddenly there was a massive slow motion bright blue fork lightning across the sky. Never seen it blue before been fasinated with fork lightning for years, [cannot watch the flash lightning hurts my eyes and gives a headache].

  bumpkin 22:26 28 Jul 14

Impressive stuff nature click here

  Forum Editor 23:10 28 Jul 14

"Never seen it blue before"

All lightning is blue-white in colour. The colour is a result of the extremely high temperature of the discharge - about 30,000 degrees Kelvin -exciting nitrogen in the air.

  morddwyd 08:45 29 Jul 14

It depends a bit on the angle of view and dispersion of he light, just as dust makes sunset and sunrise go to the opposite end of the spectrum.

Many Bomber Command aircrew believed, and still do, that there were blue "master searchlights" in the Ruhr during the war.

If you were directly above the searchlight, and held in it, it appeared blue , and if you were held all other searchlights would home in.

Research after the war revealed no evidence of blue searchlights.

  sunnystaines 15:55 29 Jul 14

morddwyd I sometimes see a blue tinge in some car headlamps

  Forum Editor 15:56 29 Jul 14

"It depends a bit on the angle of view and dispersion of he light, just as dust makes sunset and sunrise go to the opposite end of the spectrum."

Sunsets are red for two reasons. When the sun is near the horizon the light has to travel through more of the earth's atmosphere before it reaches your eyes, and the dust that is present scatters more of its light, until less of the shorter, blue wavelengths get through. We end up seeing the long wavelength, red light.

Angle of view doesn't have anything to do with what you see in a lightning flash. That looks blue-white because nitrogen is being excited by the enormous energy flow. The blue-white color is caused by light emitted as the electrons drop back to their original energy states.

Dust in the atmosphere can certainly cause colour tinges in lightning, as morddwyd suggests.

  BT 17:39 29 Jul 14

sunnystaines

"I sometimes see a blue tinge in some car headlamps"

There are automotive bulbs available with a blue tint. Some are very blue, others less so. The Xenon lamps some people fit are very blue/white and bright and depending on the type not strictly legal, and will often result in MOT failure. My young neighbour has them and puts his ordinary bulbs back when his MOT is due.

I have some Osram 'Nightbreakers' in my headlamps which have a blue band around half of the bulb. These lamps are slightly overrun which makes them brighter and the blue tinge makes them appear whiter. The downside of them is a slightly shorter life but so far this hasn't caused me any problems.

  sunnystaines 08:07 30 Jul 14

bt

thanks thought it was part of my eye problems

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