Did you know that New York City’s light pollution can be seen from space? It’s no secret that the amount of artificial light in cities is unhealthy not only for the well being of its inhabitants, but also for the environment. Based on this reality, scientists and researchers started designating “dark-sky areas,” places where light pollution has not yet had a substantial impact, not only in North America, but across the world. Their findings have resulted in an interactive map powered by Esri, called “Are the Stars Out Tonight?

Finding a dark-sky spot is a big deal, and for more than 30 years, organizations such as DSAG, the Dark Skies Advisory Group and the International Dark-Sky Association (IDA) have been working on not only identifying the dark-sky places around the globe, but also protecting the sites from artificial light pollution in order to preserve the areas for future generations.

The website explains the story behind the project, a short history on urbanization and the proliferation of artificial lights, and the impact of light pollution on plant and animal life. Five types of dark-sky categories are used on the map, broadly following the IDA categories (and with reference to DSAG and other classification systems): Gold, Silver and Bronze-Tier Dark-Sky Places, Dark-Sky Community and Dark-Sky Discovery Site. Unfortunately, there’s no dark-sky spot in New York, but the closest is the Cherry Springs State Park in Pennsylvania, a Silver-Tier International Dark-Sky Park, not so far away from the city.

Next, check out more fun maps, including New York City in the 1980s and X-Ray Maps of What Subway Stations Actually Look Like.