http://www.pbs.org/wgbh/nova/blogs/physics/2015/03/dark-matter/
Mar 28, 2015 #1 TomTerrific Well-Known Member Rating - 0% 0 0 0 Jul 11, 2010 4,061 38 Centre, Ky http://www.pbs.org/wgbh/nova/blogs/physics/2015/03/dark-matter/