450 likes | 1.03k Views
Light Pollution. Why is light directed upward?. Light directed upward is wasted. Los Angeles from Mount Wilson Observatory 1908. Los Angeles from Mount Wilson Observatory 1988. Wouldn’t it be more effective to put the lights above and direct it down?. Too much light goes upward.
E N D
Los Angeles from Mount Wilson Observatory 1908
Los Angeles from Mount Wilson Observatory 1988
Wouldn’t it be more effective to put the lights above and direct it down?
Too much light goes upward. needs better shielding
better shielding very little goes up
Street Light Spectra Low Pressure Sodium High Pressure Sodium Mercury Vapor
Street Light Spectra Low Pressure Sodium High Pressure Sodium Mercury Vapor
Street Light Spectra Low Pressure Sodium High Pressure Sodium Mercury Vapor
Low Pressure Sodium best outdoor lighting for all safety concerns pierces fog expensive bulb energy efficient brighter than high pressure sodium
Why don’t you like low pressure sodium? don’t like the color can’t see color looks like the traffic signal exceptions?
Crime 98% 80% Adequately Illuminated 2% 20%
loss of night vision glare
Light Pollution Losing Battle Rational Argument Against Emotional Argument in Favor Population Growth
San Diego Southwestern College Texas High School aircraft carriers NY subways