How does light pollution affect astronomers? And what can be done about it?
In a nutshell, two elements of light pollution affect astronomers most: skyglow and light trespass. Skyglow is a result of fixtures which emit a portion of their light directly upward into the sky where the light scatters, creating an orange-yellow glow above a city or town. This light can then interfere with sensitive astronomical instruments trying to capture light from distant galaxies. Light trespass occurs when poorly shielded or poorly aimed fixtures cast light into unwanted areas, such as observatory and buildings.
This light also interferes with astronomical instruments. What can be done: use fully shielded light fixtures, those which put light only where it is wanted and needed, not up into the sky where it is useless, or onto neighboring properties where it will affect others. Also, certain light sources are more ‘astronomically friendly’ than others. Low Pressure Sodium (LPS) lights are preferable near observatories, whereas Metal Halides are less preferable.
Source: www.darksky.org
Add comment October 29th, 2007