BOSS Conceptual Illustration (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption BOSS measures the three-dimensional clustering of galaxies at various redshifts, revealing their precise distance, the age of the universe at that redshift, and how fast the universe has expanded. The measurement uses a "standard ruler" based on the regular variations of the temperature of the cosmic microwave background, which reveal variations in the density of matter in the early universe that gave rise to the later clustering of galaxies and large-scale structure of the universe today. Credit Credit: Eric Huff, the SDSS-III team, and the South Pole Telescope team. Graphic by Zosia Rostomian Usage Restrictions Credit required License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.