Researchers from the Baryon Oscillation Spectroscopic Survey (BOSS) that include CCAPP scientists announced this week that they have measured the distances to galaxies more than six billion light-years away to an unprecedented accuracy of just one percent. The measurements utilized so-called "baryon acoustic oscillations (BAOs)", subtle periodic ripples in the distribution of galaxies, as a standard ruler to measure the cosmic distance to these galaxies. Their measurements place new constraints on the properties of the mysterious "dark energy" thought to permeate empty space, which causes the expansion of the Universe to accelerate. In addition, the team tested the gravity theory at cosmological scales with 10% precision by measuring the velocity fields of the galaxies that were induced by gravity.