July 2002

Class 1: Excellent dark-sky site - Black

Class 2: Typical truly dark site - Gray

Class 3: Rural sky - Blue

Class 4: Rural/suburban transition

Class 5: Suburban sky

Class 6: Bright suburban sky

Class 7: Suburban/urban transition

Class 8: City sky - white

Class 9: Inner-city sky - White

See scale definitions page

Also see the Maryland IDA Chapter at: http://www.mdida.org/

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