light pollution

Light pollution is an ambient background and direct artificial light that interferes with astronomical observations; it does this by reducing the contrast of celestial objects with the sky, thus limiting the ability to see faint sources. Groups of volunteers around the world are now showing that effective laws and guidelines can be instated at the local and regional levels of government, which mean that proper outdoor night lighting can be a norm so that everybody benefits-auto drivers, sleeping residents, government budgets, and astronomers alike. Laws mandating full-cutoff light fixtures are already in place in states such as Maine and Connecticut and are pending in some others.