http://hetdex.org/dark_energy/dark_matter.php
http://chandra.harvard.edu/xray_astro/dark_matter/index.html
http://science.nationalgeographic.com/science/space/dark-matter
http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/
https://medium.com/starts-with-a-bang/10-facts-everyone-should-know-about-dark-matter-1ce2b222cf08#.1h01u1tqs
http://www.space.com/20930-dark-matter.html
http://www.cosmosup.com/interesting-facts-about-dark-matter/
http://www.quantumdiaries.org/wp-content/uploads/2013/06/disk-dark-matter.jpg
http://chandra.harvard.edu/xray_astro/dark_matter/index.html
http://science.nationalgeographic.com/science/space/dark-matter
http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/
https://medium.com/starts-with-a-bang/10-facts-everyone-should-know-about-dark-matter-1ce2b222cf08#.1h01u1tqs
http://www.space.com/20930-dark-matter.html
http://www.cosmosup.com/interesting-facts-about-dark-matter/
http://www.quantumdiaries.org/wp-content/uploads/2013/06/disk-dark-matter.jpg