Light Pollution

In urban areas light pollution can hide the stars and get in the way with astronomy. In settings near astronomical telescopes and observatories, low pressure sodium lamps may be used. These lamps are beneficial over other lamps such as mercury and halogen lamps because low pressure sodium lamps emit lower intensity, monochromatic light. Observatories can filter the sodium wavelength out of their observations and almost eliminate the interference from nearby urban lighting.The light pollution also disrupts the natural increasing cycle of plants.