The universe just got a new speeding ticket. The most precise measurement ever made of the speed of the universe's expansion is in, thanks to NASA's Spitzer Space Telescope, and it's a doozy. Space itself is pulling apart at the seams, expanding at a rate of 74.3 plus or minus 2.1 kilometers (46.2 p Full story
The galaxy cluster Abell 1689 is famous for the way it bends light in a phenomenon called gravitational lensing. A new study of the cluster is revealing secrets about how dark energy shapes the universe.