Light pollution is the alteration of the natural patterns of light and dark in ecosystems, resulting from the unnecessary and inefficient use of artificial lighting. Specific categories of light pollu
Light pollution over Melbourne, Australia
A light pollution source, using a broad spectrum metal halide lamp, pointing upward at Uniqema factory, Gouda, the Netherlands
The city of Phoenix, seen from 55 miles (89 km) away in Surprise, Arizona
An office building is illuminated by high-pressure sodium (HPS) lamps shining upward. Much light goes into the sky and neighboring apartment blocks, causing light pollution.
The Milky Way or Milky Way Galaxy, or simply the Galaxy, is the galaxy that includes the Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the nig
Light pollution
…Europeans and Americans, live under light-polluted skies that are more than 10% brighter than natural darkness. 80% of North Americans cannot see the Milky Way galaxy. Light trespass occurs when unwanted light enters one's property. A common light trespass problem occurs when a strong light enters the window…
The Galactic Center as seen from Earth's night sky (featuring the telescope's laser guide star).
The Milky Way as seen from a dark site with little light pollution
Photograph of the "Great Andromeda Nebula" from 1899, later identified as the Andromeda Galaxy
A diagram of the Sun's location in the Milky Way; the angles represent longitudes in the galactic coordinate system