City lights can look pretty spectacular at night, but for a significant minority of Earth's population they're obscuring an even better light show: the Milky Way.
In news that will be no surprise to anyone who lives in a city, a scientific paper out on Friday in the journal Science Advances shows that 1 in 3 people on Earth can't see the Milky Way with the naked eye because of light pollution. "A third of the population of Earth cannot see the Milky Way from their living places," Fabio Falchi of the Light Pollution Science and Technology Institute, an author of the paper, told BuzzFeed News.
If you're one of the people who can't see it, this is what you're missing out on:
The scientists have created an atlas showing where in the world is most light-polluted, and where you can still see our galaxy across the night sky.
A decade ago Falchi and colleagues created the first atlas of artificial sky brightness across the world, and now they've updated it thanks to more precision measurements.
They define skies as "light polluted" when the level of artificial light makes the sky 10% brighter or more than natural levels, making it difficult to undertake astronomical observations. According to this definition, 80% of the world’s population live where the night sky is considered polluted by astronomers, says Falchi.
The spectrum runs from dark grey (no light pollution) to white (the most light pollution).
Blue and green highlight areas that are light polluted, but where it's still possible to see the Milky Way.
"The winter Milky Way (fainter than its summer counterpart) cannot be observed from sites coded in yellow, whereas the orange level sets the point of artificial brightness that masks the summer Milky Way as well," write the authors.
In red areas the night sky is five to ten times brighter than it would be naturally. "This means that, in places with this level of pollution, people never experience conditions resembling a true night because it is masked by an artificial twilight," write the authors.
This is what it looks like over Europe, Africa, the Middle East, and India.
As you can see, it's good news for most of Africa, but very bad news for most of Europe. If you want inky black skies in western Europe, Sweden, Norway, and Scotland are your best bet.
The U.S. fares slightly better than Europe, but not by much. Canadians are doing a lot better in comparison.
Most of the results of the analysis are exactly as you'd expect: Big cities have the most light pollution, and along the coast your chance of unobstructed sky-gazing goes up.
If you like your nights dark, head to Chad, Central African Republic, and Madagascar – more than three-quarters of people who live in those countries live under what the authors call "pristine skies".
Large parts of Asia have dark skies, but it also hosts the most light-polluted country: Singapore.
"The entire population [of Singapore] lives under skies so bright that the eye
cannot fully dark-adapt to night vision," write the authors.