Shimering City Lights

[ally_cat]

When you are on a hill, looking down at city lights why do they appear to be shimmering?

[Gef]

For the same reason that stars seem to 'twinkle'. The light had to travel through air at different densities (temperatures).

[darth vader]

(just to expand on Gef - ooer!) there is a lot of heat coming off a city. The light travels through this heat, then through the cooler air where you are stood, hence a temperature differential. The same effect seen driving down a road on a hot day can be explained by this also.

[IggyB]

but what is the twinkling?

[bazwillrun]

Chromatic Aberration

[anastacia]

It's the distance you silly dilly!!