What's that on the Horizon?: A brief explanation on light pollution.
The sky brings many various things to offer; stars, nebulae, galaxies, planets, etc.
Oh and let's not forget that city light glow on the horizon as well. . .
Light pollution is a rather "first world" yet still understated issue that is growing at an uncomfortable rate. It's the almost scary effect in which we are blinded by the very thing we invented to help us through the dark. Blinded from the truth, the rather beautiful truth indeed.
Of course lighting up the night to make our everyday lives safer, easier, and a bit less scary is not something to be worried over, no, what concerns me and observers around the globe is how light pollution is something we could easily stop, but nobody cares enough to do so.
Think about this for a second; what is the purpose of zoos? What do they offer aside from just entertainment?
The answer is simple; Enlightenment
Children's eyes are opened to the reality that the world is filled with beautiful creatures which we must care for and protect from ourselves, without seeing them face to face, what kids would even care about illegal lion poaching or protection of animal environments?
Now apply that same concept to the night sky, what you'll realize is that the growing population who've never witnessed a true natural sky of the dark is a growing population of people who don't care. Around 80% of people in the United States have never witnessed the band of the milky way. That's quite a few.
It doesn't help that light in the night is becoming extensively cheap and bulbs and lamps are not made with sky preservation in mind. But believe me, it is very possible. And you'd never have to shut off any of you're artificial night vision to do so. All that needs to be done is make light more efficient, as in, make produced light only go where it's actually needed; the ground. Have street lamps cupped so that the light flying off into the sky is blocked, close blinds where your indoor lights are on, have lights built with top covers.
These are all things that could cost the world very little, and would change so much. And before you go and say, "It's not like it's the end of the world if some suburban residents can't see the stars. . . ", I'd like to elaborate that this overhead view is not a mere pretty spectacle, but a way for humans to re-evaluate their very lives.
As almost anyone who's lived under light-polluted skies and then once seen the true night sky would tell you, you don't walk away from a first time milky way view the same as before. For once in your life you begin to realize where you are, and what there is. Many people who watch the stars for a long period of time will experience something called grounded disorientation, the sensation in which you lose you sense of stability even while lying down, as you realize you're not looking up, you're looking out.
Oh and just for fun, here's an mock up someone made showing what Rio would look like stripped of light pollution:
Picture origins:
https://www.pinterest.com/pin/90212798757716447/
http://www.iflscience.com/space/what-if-our-cities-were-lit-billions-stars/
Info Sources: None, just kinda mixed knowledge from tons of sources