<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://pop.h-cdn.co/assets/cm/15/05/160x160/54cad1681c026_-_backyard-astronomy-07-0911-mdn.jpg>
<http://www.popularmechanics.com/space/telescopes/g637/how-to-become-a-backyard-astronomer/>