When was the last time you looked up at the night sky and glimpsed the Milky Way? Last night? A year ago? Never? Some 80% of North Americans can no longer see the galaxy due to light pollution, or skyglow.

Light pollution causes a profound ecological disruption that affects human health, alters animal migratory patterns and obstructs astronomical research. Recent findings even suggest higher breast cancer rates may result from artificial day conditions created by over-lighted cities and the consequent suppression of nocturnal melatonin production. It’s estimated that one third of the world’s population lives under light-polluted skies, a situation worsening dramatically with aggressive urban expansion.

To bring attention to the problem, we traveled across the continent using long exposure DSLR photography to capture the cosmos from North America’s endangered “dark sky” locations. Despite its immense population, we still found some of the best shots in our own backyard of Southern California. Each photo was exposed for 25 seconds, allowing galactic details to flood in — far more than can be seen with the naked eye. The psychedelic “star trails” effect in many of the pictures was created by tracking the rotation of the Earth’s axis over several hours as our cameras fired continuously, operated by remote controls known as intervalometers.

Night isn’t just a darker version of day, it’s our chance to see the universe — or it was once, and could be again if we understood light pollution as the environmental tragedy it really is.

Superbloom — Death Valley National Park

(Harun Mehmedinovic / Skyglow Project)

U.S. Route 40 — Mojave National Preserve

(Harun Mehmedinovic / Skyglow Project)

Ghost town constellations — Cerro Gordo

(Harun Mehmedinovic / Skyglow Project)

The Perseids — Mojave National Preserve

(Harun Mehmedinovic / Skyglow Project)

Clear skies — Owens Valley Radio Observatory

(Harun Mehmedinovic / Skyglow Project)

Gavin Heffernan and Harun Mehmedinovic are the co-creators of the Skyglow Project.

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