natural light

The Disappearing Darkness - John Barentine

Photo of Bonito Park (top) in Flagstaff, Arizona, by Deborah Lee Soltesz. Credit: Coconino National Forest, U.S. Forest Service. Bonito Park is just west of Sunset Crater Volcano National Monument, an IDA-designated Dark Sky Place.

Photo of Bonito Park (top) in Flagstaff, Arizona, by Deborah Lee Soltesz. Credit: Coconino National Forest, U.S. Forest Service. Bonito Park is just west of Sunset Crater Volcano National Monument, an IDA-designated Dark Sky Place.

We are fundamentally transforming the nighttime environment in the world in a way that is utterly unlike anything that the world has ever seen in the past.
— John Barentine

Sometimes when I’m up at night thinking about the inexorable alteration of the human existence since my own childhood and in the mere 150 years since America’s Industrial Revolution (yup, this is my brain not on drugs), what haunts me most is this: My two little girls -- and entire generations of human beings -- are now growing up without seeing the stars.

And it’s not only megacity-dwelling people like us: Because of the ceaseless lights of our cities, suburbs and their surrounds, an astounding 80 percent of the world now lives under perpetual skyglow. In fact, two-thirds of Americans have lost the ability to see the Milky Way, and an unfathomable 99 percent of people (not to mention animals and plants) living in the United States and Europe will never experience the circadian rhythms of true darkness and natural light.

Not surprisingly, there is a growing body of evidence on how our disconnection from the darkness may be profoundly impacting human health, not to mention its link to our modern-day epidemic of cancer and chronic disease. But I have bigger questions: What does it mean to the human existence, to our human souls, that we can no longer see and therefore dream about the heavens; that we no longer look up at the night sky and innately recognize our millions-year-old relationship with the universe?

These were some of the topics at hand in my fascinating conversation for today’s episode with John Barentine, an astronomer who’s made it his mission to bring back the natural night sky in his work with the International Dark-Sky Association. John has had a remarkable career as an astronomer (a former researcher at NOAO and the NSO, as well as a former staff member at Apache Point), author and science communicator -- the last of which is apparent when you listen to John so eloquently deconstruct and discuss this epic topic, as well as inspire us on how to take action on light pollution and change our children’s literal vision of the future. 

Here’s what we talked about:

  • Recent natural disasters, and witnessing true darkness in their aftermath: “What was the mysterious glowing cloud in the night sky?”

  • The disconnect between humanity and our access to the night sky

  • Why the industrialized world isn’t talking more about light pollution

  • The history behind the International Dark-Sky Association

  • Limiting artificial light at night: Light for its own sake versus light for specific tasks

  • Light pollution, explained: What we’re facing on a local and global scale

  • What the world was like before the advent of electricity a mere 120 years ago: “All life on earth evolved in those conditions”

  • The impact of artificial light (and nighttime darkness) on human biology

  • The ancient history of the circadian rhythm

  • The connection to chronic disease, mental illness and epigenetic changes

  • Pre-agricultural societies and our relationship to the night sky throughout human history

  • Dark-sky awareness in John’s city of Tucson, Arizona

  • How outdoor lighting policy changes can bring back the night sky

  • The truth about lighting, crime and safety

  • Making the case to take action on light pollution and the single most effective thing you can do to help

  • More resources to help you take action

  • The International Dark Sky Places program, dark sky tourism and how to become an International Dark Sky Community

  • What it’s like to live with a natural level of darkness, and where to go to truly see the night sky

  • The challenge of the developing world and John’s hope for the future

  • The story behind John’s books The Lost Constellations and Uncharted Constellations

You can learn more about John’s work and the urgent issue of light pollution (along with how you can take action) on the International Dark-Sky Association website, as well as follow IDA’s work on Twitter, Facebook and Instagram. John’s personal website is at and he himself has a terrific Twitter account; you can connect with him @JohnBarentine.  

John's books:

If you enjoyed this show, subscribe on iTunes so you don’t miss the next one (and don’t forget to leave a rating and review). The theme music is by Paul Damian Hogan. Want to chime in on this episode or have an idea for a future show? Connect with me via my Instagram page, I’d love to hear your thoughts!

Resources / further reading:

IDA film: Losing the Dark
National Geographic: “Light Pollution
Gizmodo: “Streetlights Don’t Actually Prevent Crime
Curbed: “How dark sky communities fight light pollution
LA Times: “Light pollution prevents 1 in 3 Americans from seeing the Milky Way at night
The New Yorker: “The Dark Side
FiveThirtyEight: “The Darkest Town in America
National Park Service: “What Happened to the Night Sky?”
The new world atlas of artificial sky brightness
Blue Marble Navigator – Night Lights 2012
Undisturbed Places – a time-lapse film by Maciej Tomków