Let there be a night again!

I grew up in small town of Kalyan which is located 40 kilometers from Mumbai. Back in 90's decade it was still away from the glamorous life style of metro city like Mumbai. Most of the settlements were in the form of small houses called chawls and they were far for each other. Very few apartments one could see in this town. The sky of this town was not littered with light. I remembered that we could see most of the constellations even faint ones like Cancer, Cetus and Camelopardalis. I learned to identify most of the constellations from Kalyan's sky.

In late 90's town started growing up. Toward its west we could see the light from Mumbai city glows up entire western horizon. Kalyan's light also started to erase stars and constellations from its sky. We have to travel around 60-70 kilometers away from the city to see good night sky. Nowadays we could hardly see any stars from Kalyan. These days even going 60-70 kilometers from city not work, its quite difficult to see deep sky objects from such distances.

I think most of us have seen sky with stars in our childhood (I am talking about children from 80's and 90's decade). Present day if we go in cities or any town we hardly see any stars in night sky. Nowadays cities and town are flooded with the lights. Most of the population in metro cities have never seen sky with full of stars. Even in small towns sky is not that much promising. Artificial lights have cut out us from the beauty of night sky. 

Growing city lights are erasing stars from their sky, Source:internet

One incidence I remember from one of my sky gazing camp. One of my friend from Mumbai also joined us. She suddenly says, 'hey look at that big illuminated cloud it's looking amazing', I said, It's a center of our milky way'. She was stunned by view. She said she had never seen such wonderful object in sky. Most people from city never see such sites in sky. 

We have heard lot about different kind of pollution like air, water, noise and soil. These kinds of pollution directly affect environment and health of humans. So, that's why we are more concern about these pollution. But, there is one more kind of pollution is growing up and that is light pollution. Excess use of light is called as light pollution. We do not bother about light pollution and there no direct effect light pollution on our heath. So, we humans are lighten up more lights with growing cities. But, it does not mean that it not harmful by any means. We might say we don't need nights. But, nights are important to us. Too, much artificial light can cause sleep disorders which further causes many more diseases. You can find more detail about it on this link http://darksky.org/light-pollution/human-health/

Too much light impacts our night. Night give us sense of time. It also help in propelling our biological clock. Not only us but also many animals biological clock derived by day and night. We have disturbed this by using more and more artificial lights. Migratory birds need good night sky view to travel, but due to light pollution they loose their path and most of time get exhausted in flying and die. 

Now many countries are started glowing during nights. It is very necessary to aware people about importance of night. With increasing population, cities and societies we need light for many purposes but we also should understand how much to use and when to switch it off. In many countries people are started doing this. They aware and educate people to use light sensibly. In India too we need this where cities and towns are growing. 

If we look back in history, we find that night sky has shaped our human civilization than any other thing. Night sky gave us direction for travelling on our globe. Clear night skies told us there is cycle in some events which we can use as calendar. Observing night sky developed understanding of our place in universe. Night sky has inspired our religion, philosophy, art and science. This is the one heritage that all civilization shared. But, because of uncontrolled use of artificial lights our present generation is loosing this. Its time to get aware about using light with responsibly and preserve this heritage. 

Center of our galaxy visible from dark place, source: internet

there are various organisations like Dark Skies Awareness and International Dark Sky are working in this area. You can visit their website to understand more about light pollution.