Ultraprecise measurements in XXL

The Dark Energy Spectroscopic Instrument, called DESI, has an ambitious goal: to scan more than 35 million galaxies in the night sky to track the expansion of our universe and the growth of its large-scale structure over the last 10 billion years. Using DESI—a project led by Lawrence Berkeley National Laboratory—scientists hope to create a 3-D map of a third of the night sky that is more accurate and precise than any other.