<http://schema.org/about>
"Back in October, Lloyd wrote a post on how for many people the stars don't come out anymore, all because of increasing urbanization and light pollution--it included a great image of the differences in star"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/travel/dark-sky-tourism-on-rise-as-more-people-seek-out-the-stars.html>