Google Earth and Light Pollution Monitoring

Find the Dark Spots Near You (If You Can)

The November 2007 issue of Sky & Telescope contains an article entitled, "Exploring Earth at Night," by Stuart J. Goldman [S&T]. The article describes a new feature of Google Earth that uses NASA imagery to overlay the traditional terrestrial maps with Earth's surface at night. The imagery shows the pervasiveness of light pollution. Here we can get a clear, roadmap context to the patterns of surface illumination. When you look at the image of the city of Sierra Vista at night, you may get a fright—that "deer-in-the-headlights" feeling. The problem of light pollution in our local community is going to run us over! Others may get a sickening feeling.

The night-view layer of Google Earth does not have the resolution of the aerial and satellite imagery, so you won't be able to zoom in and see if a particular house is glowing. This imagery has a resolution of a few kilometers. Maybe someday in the future we will get 50- to 100-meter resolution of the Earth at night. A "Nightsat" has been proposed in the International Journal of Remote Sensing by NOAA's Christopher Elvidge and ten colleagues, including astronaut Donald Pettit.

View some selected images from the Google Earth program on this page, or get the program and try it for yourself. The NASA imagery can be accessed by selecting the following options from the Google Earth application's Layers panel:

View: Core

Primary Database --> Gallery --> NASA --> Earth City Lights

Selected from Google Earth, NASA's Earth City Lights

(Click on the images for large versions (1048x922).)

Light Pollution, USA, Southwest, Arizona and California, 2007	Light Pollution, USA, Southwest, Arizona and California, 2012
Light Pollution, Southern Arizona, 2007	Light Pollution, Southern Arizona, 2012
Light Pollution, Southeastern Arizona, 2007	Light Pollution, Southeastern Arizona, 2012
Light Pollution, Cochise County, 2007	Light Pollution, Cochise County, 2012
Light Pollution, Sierra Vista and Ft. Huachuca Area, 2007
Light Pollution, Sierra Vista from 15 Miles Up, 2007
Light Pollution, Sierra Vista from 29,057 Feet Up, 2007