“Guard, protect and cherish your land, 

for there is no afterlife for a place

that started out as Heaven.”

— Charles Marion Russell (1929)

WHAT IS LIGHT POLLUTION?

Light pollution is artificial light that serves no useful purpose while causing unintended ill effects. Point sources of bright light (like LEDs) create blinding GLARE that reduces our ability to see at night. Improperly shielded fixtures dump nuisance light TRESPASS onto nearby private properties. Light CLUTTER overwhelms our senses and causes our pupils to constrict, which greatly reduces our ability to see into the shadows. And light shining up into the sky instead of on the ground (where we need it!) creates a dome of SKYGLOW over our towns and cities that can cause serious health issues while blinding us to the stars above.

GLARE

Unshielded light fixtures create blinding glare from LED point sources

TRESPASS

Town streetlight shining into bedroom windows on nearby private property

CLUTTER

Too many lights causes light clutter that can disorient drivers and pedestrians

SKYGLOW

Skyglow over Polson and Missoula, as seen from Kalispell (Blacktail Mtn.)

IS LIGHT POLLUTION REALLY A SERIOUS PROBLEM?

Montana is blessed with patches of still-dark, rural night skies. If light pollution would just stop growing, Montana would be in better shape than most states. But light pollution just keeps growing and spreading. World-wide, light pollution is expanding at double the rate of population growth. In the U.S., light pollution is increasing at 6% per year. And in Montana, all of our light pollution has spread across our ‘Big Sky’ since 1880, the year that both Charlie Russell and artificial electric lights arrived.

Just a few generations ago, everyone in Montana enjoyed a pristine night sky filled with stars. Now, 80% of our citizens live under light polluted skies where only a few of the brightest stars are visible through the skyglow — and the Milky Way is missing. At the same time, light pollution wastes our money, compromises our ability to safely walk and drive at night, damages our health and threatens our native wildlife. We can do so much better with common sense solutions at little or no additional cost.

Montanans have a choice. We can ignore the issue, do nothing and loose the remaining patches of pristine skies that our grandparents enjoyed. Our nightly ‘Big Sky’ will become a glowing fog, barren of stars, northern lights and other celestial delights. Or, we can take common sense measures that save money and give us better, safer lighting that also brings back our dark night sky heritage for our children and grandchildren. Which path do you prefer?

 

Light Pollution Growth in Montana Over the Last Six Years (2013-2019)

Data from VIIRS instrument on NOAA satellite (click on any image to enlarge)

Dark Sky Locations Around Montana

Montana locations that are still dark at night but threatened by the continued expansion of artificial light

The International Dark Sky Association (IDA) Montana Chapter is the official IDA chapter for the Big Sky State.