[X] My Assistant

[dvandorn]

When I see meteors flash across the night sky, they always appear generally as streaks of white light. However, bright meteors leave a trail in the sky. It persists long enough that it's obviously not just an afterimage in the retina, it's a real, visible trail of plasma left in the wake of the meteor.

Whenever I see this phenomenon, the meteor trail looks greenish to me -- greenish with a slight yellowish tinge.

Does anyone know if that's the true color of the plasma, or is it a color trick played by the mind because of the retina's lack of color receptors at such a low light level? Or does it have more to do with the wavelengths of light scattered by the atmosphere -- maybe it's really a golden light, that gets scattered towards blue in its trip through the troposphere?

Anyone have any thoughts?

-the other Doug

[AndyG]

Whenever I see this phenomenon, the meteor trail looks greenish to me -- greenish with a slight yellowish tinge.

Green is good - it's the same green as you get in auroral discharges: it's the emission of photons from atomic oxygen, here plasmarised by the heat and friction of a passing meteor, and not by high speed charged particles as in aurorae.

Andy G

[paxdan]

Green is good - it's the same green as you get in auroral discharges: it's the emission of photons from atomic oxygen, here plasmarised by the heat and friction of a passing meteor, and not by high speed charged particles as in aurorae.

Andy G

of course by friction you mean ram pressure