Light Polution Changing The Way oOf Mother Nature
Tonight, when you’ll walk outside and look up, you’ll see some faint lights flickering. You know they’re stars. You know that only the brightest can be seen with the unaided eye. You know telescopes are expensive. In conclusion, you see the ones with the highest apparent magnitude, just some dim flickers in the sky. “Why is the night sky so orange, though?” you raise your eyebrow. Then the world cuts off electricity, and ‘borrows’ all the generators (just for a moment, you can live without Wi-Fi), turns the lights off, and then, this:
Depiction of what San Francisco would look like without light pollution
W O A H
Today, you see light pollution as skyglow (light that clouds the skies above), glares (lights that irritate your retinas), and that annoying holiday lighting trespassing from your annoying neighbors.
This seems like a trivial situation, doesn’t it? Well, consider the fact that, often, astronomers want to take the spectra of an object, splitting the light from the telescope into its component colors. When a spectrum of fluorescing objects like galaxies is taken, you see that the spectrum is made up of a number of lines. Each line is a unique indicator of the presence of a certain chemical. By studying the strengths of these lines, astronomers can deduce the chemical composition and temperatures of the objects they observe. Spectroscopy is probably the most valuable tool in the astronomers’ toolbox.
Regrettably, city lights did this:
Spectrogram of a galaxy in the constellation Hercules – The bright horizontal line through the middle is the light of the galaxy we observed that night. The bright vertical lines that you see are not from the galaxy: they are lines from mercury vapour lamps in San Diego! The lines from the galaxy are actually dark against the light of the galaxy, but they are very difficult to find (try it!) because they are lost in the bright lines from the city. “Aw, no! The astronomers aren’t happy! “Unfortunately, there is no kind of counteractive lens that they can use to clear out all the pollution. Any filter that they used to filter out the unwanted light would also filter out the light they want to see.
Another thing to consider is about the night life. When you’re being insomniac on the internet, there is an ample amount of nocturnal creatures relying on their instincts to survive. The polarization of the moonlit sky is very strongly reduced in the presence of urban light pollution because scattered urban light is not strongly polarized. Since polarized moonlight is believed to be used by many animals for navigation, this screening is another negative effect of light pollution on ecology.
Light pollution is mostly unpolarized, and its addition to moonlight results in a decreased polarization signal.
(Okay, if you didn’t get this thing, think like this: Weird rainbow is good, scary red is bad.)
In addition, Medical research on the effects of excessive light on the human body suggests that a Variety of adverse health effects may be caused by light pollution. Ever feel like tumbling down to your bed and sleep for some aeons but your eyes just don’t shut, and then anxiety takes over you, and you wish you had a lot of kitties? This might be related.
Would you like the thought of living life without that breath-taking view of the Milky Way enthralling your eyes? I know you wouldn’t (if you would, then you’re edgy). Believe me, There’s things we can do.
The International Dark-Sky Association’s mission is “to preserve and protect the night time environment and our heritage of dark skies through quality outdoor lighting.” Light pollution is the result of outdoor lighting that is not properly shielded, and we need more efficient systems. What about conserving energy? We could shine lights downwards instead of up – I mean, we don’t need to light up the sky. Ooh, glow-in-the-dark roads (Awesome stuff, Netherlands)!
We’ve come to realise that we’re losing a part of ourselves when we noticed our waning connection with the stars. We brought the light of the cosmos to Earth to appreciate every heavenly fragment our eyes met and then, just forgot about them.
We’ll fix this, just with sufficient determination, we’ll bring back the empyrean.