Light Pollution

This is a picture taken from space showing the prominent light sources of the eastern side of the United States. Yes, our lights on earth are indeed bright enough to be seen from space! The topic today is the biggest stumbling block to good stargazing (other than clouds) that one can face: light pollution. This post will cover the light pollution that occurs outside on a starry night, and not the kind that can happen indoors.

Air, being made up of molecules, is not perfectly transparent like we believe it to be. Light works by reflecting off of a surface, and our eyes pick up that reflection. Even on a dark night, the molecules in the air and the atmosphere surrounding the earth will reflect the light emitted by anything. Any extra light will make it harder to see the stars in the sky. The more lights you are around, the less stars will be visible. The rather bright spots on the map above are areas where cities are located. You can see the difference in light emissions from a city to the country.

The best places to see stars is away from any light. The countryside is always optimal stargazing country. Even if there is a little light, however; it will not ruin your whole experience. A place I frequently stargaze is not far from a small city, yet plenty of stars are still visible. City dwellers, there is always hope! A short drive out into the country is usually enough to eliminate most glare from city light as well. If you are diligent, you can always find a good place to stargaze, just be wary of light pollution.