Roughly 5,000 stars are visible from Earth, but you've never seen most of them. If you live in a city, you may not see any of them. Filmmakers Gavin Heffernan and Harun Mehmedinovic let us glimpse the wonders of space with their sweeping long-exposure photos and time-lapse videos that reveal the cosmos in all its glory.

Light pollution brightening the night sky in populated areas, or skyglow, is why urbanites often see nothing but darkness when they look up. Skyglow increases exponentially each year as the world's metropolitan areas grow and grow and grow. Research has linked light pollution to everything from disrupted sleep patterns to the death of migratory birds. Although people may realize they see fewer and fewer stars, it’s rarely given much consideration. Mehmedinovic, who was born in Bosnia, remembers the first time he realized he hadn’t seen a star.

"When I came to the US and landed in Phoenix, it took me a while to realize I couldn’t see the stars at all," he says. "It wasn’t until I started doing road trips across the country that I saw them, and had a flashback to early childhood."

That loss inspired them to embark on a journey of rediscovery. They've been shooting the stars for several years now, but now they plan to travel throughout North America to chronicle the few “dark sky” regions left in our light-saturated world.

The Wave Vortex, Arizona. Harun Mehmedinovic

Making the photos requires infinite patience. They'll space half a dozen or so cameras across several miles of terrain; each makes 25-second exposures repeatedly for two to four hours. The time-lapse videos are comprised of hundreds of these images; Heffernan says it takes around 450 photos to create 20 seconds of film. “You are creating video one frame at a time, almost like early animation,” he says.

The breathtaking photos show slivers of light streaking across the sky, bringing Van Gogh's Starry Night to life. To promote their Kickstarter, Heffernan and Mehmedinovic created a trailer that shows what Los Angeles might look like without light pollution. The film is a painstaking composite of LA city streets set against photos of the night sky in places like the Grand Canyon. They were inspired in part by the work of French artist Thierry Cohen, who used a similar trick to create a series of photos showing what major cities might look like illuminated only by stars.

Two timelapse cameras capturing light pollution over downtown Los Angeles. Taken from Mount Wilson, Ca, 2015. Gavin Heffernan & Harun Mehmedinovic

The filmmakers hope to publish a book and DVD that present their images alongside research on light pollution, astronomy and "the impact of stars on imagination, mythology and the sciences." Though skyglow is pervasive, it’s not unsolvable. The artists argue that simply ensuring lights point downward and are properly shaded would improve things. They hope showcasing the wonder of the night sky will make people see what they're missing and inspire them to do something about it.

"They say a picture is worth a thousand words," says Mehmedinovic. "Simply shooting the stars is a form of activism because you don’t see them anymore."

Heffernan and Mehmedinovic's project Skyglow is currently seeking funding through Kickstarter, ending May 9th.