Can’t See the Milky Way? Here’s Why!

Chances are you’ve seen the story over the past week about how the Milky Way is now hidden from at least a third of people on this planet. because of light pollution. In fact, chances are you ARE one of those people. Think about the last time (if ever) that you saw this band of light stretching across the sky.  If you can’t, it’s entirely likely that it’s invisible to you due to our indiscriminate use of light at night. Think about that — our home galaxy is hidden away from view for millions and millions of people behind a wash of entirely preventable light pollution. It’s our connection to the cosmos, and it’s been lost for many people.

I’m not gonna mince words about this: we spend/waste billions of dollars each year lighting up the sky. It doesn’t make the sky safer (and if lights are pointing UP or scattering light OUT instead of DOWN, they’re not making you and me safer at night), but it does wash out the view of the stars.  And, it has other effects that are now being measured.

Ask anybody in a big city (or near one) about the Milky Way and if they haven’t seen it, they probably don’t even know what it is or what it looks like. Chances are the folks in the biggest metroplexes have seen only a few stars or a bright planet or two in their lifetimes. I find that incredibly sad.

Big deal, you say. So what if we can’t see the stars?

Yeah, I’ll grant you that — particularly in the face of some of the other heinous crap that’s happening on this planet (can we say hate crimes, political chicanery, war, and other stupidities?) — maybe light pollution doesn’t rank up there as important. But, as I mentioned above, losing the dark has more than one effect, aside from draining our collective wallets to pay for expensive fossil fuels (in many places) to light up the sky.  The sky is but one symptom of larger problems we face.

Too much light at night has a definite health effect on humans, plants, and animals. This has been and is continuing to be documented by research. Glare from lights is often a factor in accidents, and improperly placed lights have been shown to decrease safety around buildings, on streets, etc. rather than increase it (as people had hoped).

Those of us who are attuned to the starry sky have known about the disappearing sky and darkness for a long time. Many of us banded together in a group called the International Dark-Sky Association to help educate people, politicians, thought leaders, school kids — whoever would listen — about how we can darken the skies yet preserve health and safety at night. It appears, if you look at this map of JUST the United States, that we still have a lot of educating to do.

Right now I’ve been working to bring this kind of info to one of our local towns near me, in hopes of fixing up the worst of the egregious lighting that residents have complained about in recent months. It’s a small step, I know, but just letting them know about the different kinds of fixtures, and wise ways to place their lighting is important. It takes time for municipalities to change, so I’ve also been talking with the owners of a new building about their lighting, as well as the local postmaster.

How Bad Is Light Pollution Globally?

It’s one thing to think, “Oh yeah, a few cities have light pollution”, but quite another to actually measure the amount of sky brightness that exists around the world. So, the folks at the Cooperative Institute for Research in Environmental Science put together a study of light pollution and its effects on night sky visibility around the world. They used high-resolution satellite data and precision sky brightness measurements to do their work. The result is the most accurate assessment yet of the global impact of light pollution. Their report is called the New World Atlas of Artificial Sky Brightness, and it shows us where the skies are brightest from light pollution around the world.

It’s an eye-opener in many ways. For example, imagine living along the Eastern Seaboard of the U.S. If you live in the Bos-Wash corridor, there are few places where you can go for a truly dark sky. Same in the NYC-Boston corridor. Where I live, outside of Denver, Colorado, we have the Denver nebula on one horizon, ruining the view of the sky in that direction. Imagine if you lived in Beijing, or Calcutta, or London, Paris, or any of dozens of other places on the planet where lights shine up into the sky. It’s a useless waste of resources, and the health of the citizens of those places is being affected. Not to mention the plant and animal environment.

The CIRES study found that light pollution is most extensive in countries like Singapore, Italy and South Korea. Canada and Australia retain the most dark sky. In western Europe, only small areas of night sky remain relatively undiminished, mainly in Scotland, Sweden and Norway. Despite the vast open spaces of the American West, almost half of the United States experiences light-polluted nights. For many, the national parks remain the last place where people can go see a starry sky free of most light pollution. It’s another reason to keep public lands public.

Solutions for Light Pollution

Eventually, I think people will come around to the idea that we don’t need to spend tons of money to light up the skies. Outdoor lighting basics are pretty easy to learn and implement once you or your town decides to do it. The cost-effectiveness of 2700K LED lights, coupled with fully shielded light fixtures pointed DOWN (away from the sky) is already winning over a growing number of municipalities. But, it’s going to take a lot more effort on the part of everyone, from folks lighting up their porches and backyards to political awareness of what constant unneeded lighting is doing to people and their health. It’s way more than access to the stars, but the stars are like the canary in the coal mine, warning us that as we shut off our view of the Milky Way, we’re doing something not so wonderful to our health, environments, and wallets.

If you want to find out more about how to mitigate light pollution in your own backyard (or municipality), check out the International Dark-Sky Association’s web site as well as my articles about it here and here. Also, check out the video called Losing the Dark that I and my partner made about the effects of light pollution. It’s free for download for use in fulldome theaters and in flat-screen format for lectures and other public presentations.

The dark is ours to regain. We CAN learn to use lighting wisely, and bring the Milky Way back to more people.