Astronomical Light Pollution
Skykeepers founded
September 1, 1999
This web site strikes new ground in further refining the definition of Light Pollution.   Based on the premise promoted by Catherin Rich we try to show the fine points of light pollution.  Light pollution has always had a number of components; Urban Sky Glow, Glare, Light Trespass, Over Lighting, and now Ecological and Medical aspects are included (LAN & Health). 

Astronomical Light Pollution
  • Urban Sky Glow, the classic brightening of the sky over our cities and the brightening of the sky over far away observing sites such as our National Parks and Observatories.
  • Glare, a common problem for Amateur Astronomers in the form of "local" light pollution and often a component of Light Trespass.
  • Light Trespass, a common problem for Amateur Astronomers and average citizens alike.
  • Indirect Light Trespass, a term used here to indicate Sky Glow, often caused by local sources which is so severe that it is as if a flood light was directly illuminating the property from off site.
  • Related Topics, Visual Light Pollution, Ecological Light Pollution, Energy Waste
Ontario14 Aug 03 Ontario15 Aug 03
Ontario14 Aug 03 the night of the East Coast USA Blackout.
Ontario15 Aug 03 to this evening.  Once again we are denied access to the night sky.

The August 14, 2003 Blackout Night and Light Pollution
August 14, 2003, Goodwood, Ontario  28mm, f2.8, Fuji 800, 90 seconds
© 2003 Todd Carlson Please do not use without express permission from copyright holder.

It is easy to see that Energy Waste is an important component, as it takes energy to destroy the night sky.

Astro Light Pollution

Light pollution - The Wikipedia Encyclopedia view.
Light Pollution and Observing Sites - by By Jerry Lodriguss
Light pollution - Starry Night Lights view.
Energy Waste
Light Pollution and Green House Gas in Central California - How does upward wasted light contribute to Global Warming?
This page provides examples of a number of Central California Cities and the CO2 emissions that result from light pollution.
"An Introduction to the Issues of Light Pollution"  gives a good feel for how much energy we waste in the United States.
Created by long time dark sky activists Bob Crelin 
(.pdf 62k)
Natural Night Preserves
Natural Night Preserves, a local page that addresses astronomy and light pollution in our State and National Parks.  .
Dark Sky Parks and Preserves , at

Night Sky Protection

Sky Quality Measurements

The Great World Wide Star Count   -  Home Page,  Download the Activity Guide to participate!
The Great World Wide Star Count  -  Results Page,
Related Subjects

Ecological Light Pollution

Media Coverage

04 DEC 2007
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