Astronomers nail down the Hubble constant http://t.co/Zk6ZKaBeFc
— APS Physics (@APSphysics) April 9, 2014
via http://ift.tt/1juEcpD
Astronomers nail down the Hubble constant http://t.co/Zk6ZKaBeFc
— APS Physics (@APSphysics) April 9, 2014
via http://ift.tt/1juEcpD