Pollutions have been a major environmental problem for us for a long time. We are quite familiar with the four common types of pollution. Air, Water, land and noise pollution are familiar to us their causes, effects and control measures have been studied by us. Some new types like thermal and radiation pollution have also been discussed. With the passing of time, we have been facing new environmental problems everyday even while the old ones are still persisting around us. Today, I am here to discuss about ?Light pollution?. You may be familiar with it but I found this one quite new and interesting.

Light pollution or photo pollution also called as luminous pollution is simply the excessive , unmanaged and invasive use of artificial outdoor lighting in such a way that it hampers natural lighting. Such mismanaged lighting alters the contrast and colour of many natural light sources like natural starlight, nighttime sky which affects environment , humans and wildlife.  Light pollution is not something new, over the last 50 years, with the increasing urbanization and increasing demand of outdoor lightning, this phenomenon has been seen in most part of the world.

The most light polluted city of the world is Hong kong of China. A research in this area found that the night sky of this area was 1200 times brighter than a normal urban sky. Poorly designed residential, commercial and industrial outdoor lights contribute to light pollution. Unshielded and unmanaged outdoor lightning emits more than 50% of their lights to sky. Some effects of light pollution are effects on humans, wildlife, environment and energy.

So, here are some ways of preventing or reducing light pollution. We should promote the use of CFL and LED bulbs that produces warm white lightning instead of those emitting blue short wavelength. We should choose shielded outdoor lights  or a simple solid cap over the bulb which prevents light from being emitted to the sky. Selection of exterior light fixtures with cutoff angles that prevents light from escaping to the sky. If feasible motion sensors should be placed on outdoor fixtures so that they can turn off and on only when needed. The most easy one would be to turn off unnecessary outdoor lights and be involved to reduce light pollution.