Dark Sky Finder
The Dark Sky Finder shows the effects of light pollution in the United States. The map also displays user submitted sites which are good locations for setting up telescopes.
Light pollution is shown on the map via a heat map overlay. User submitted sites are displayed with simple map markers. If you click on a map marker you can view details about the submitted site beneath the map.
Users can set the light pollution layer to on or off. Users can also add their own astronomy locations to the map by completing a short form. if you find a great location on the map and you want to share it with others you can get a URL to the map by choosing 'link to this view'.
Daylight Map - Map of current current day and night time in the world. Also shows the effects of light pollution around the world.