Blinking City Lights of Krakow, Poland

November 09, 2012

BlinkingLightsOfKrakow
  

Photographer: Ania Sokulska
Summary Author: Ania Sokulska; Jim Foster

The video above showing the blinking city lights of Krakow, Poland was made from the balcony of my home at 9:33 the night of October 10, 2012. Notice that the lights in the far distance are twinkling while those nearer the camera are quiet. Blinking or twinkling of lights at night results from differences in air density. The refractive index of a layer of air is partly determined by its density. We often notice the twinkling of starlight but city lights in the distance exhibit the same behavior when air pockets of varying density move past the line of sight of the observer. This short-term defocusing causes slight variations in brightness.