Heat Distortion...

[ChaosPhoenix]

I've noticed, while looking at lights at night, that many times there appears to be something similar to heat distortion blanketing the lights. I assumed that the amount of heat coming from these lights (they were on a bridge) would not be enough to create visual distortion. My second thought was that it could be from the car emissions...But I'm still curious.

 

[Jeff7]

Astigmatism? An effect of a car/home window you're looking through perhaps?

 

[Gibsons]

Originally posted by: ChaosPhoenix
I've noticed, while looking at lights at night, that many times there appears to be something similar to heat distortion blanketing the lights. I assumed that the amount of heat coming from these lights (they were on a bridge) would not be enough to create visual distortion. My second thought was that it could be from the car emissions...But I'm still curious.

hot air rising from the hot asphalt perhaps?

 

[CycloWizard]

Typical light bulbs are less than 5% thermally efficient - almost all of the energy is used to heat the filament to the temperature required to produce the light you're used to seeing. Thus, there is quite a bit of heat leaving the lights. The 'heat effect' you see is actually density variations in the air, since air density is dependent on temperature. The air around lights is constantly in motion, trying to even out this density gradient.

/more than you wanted to know