The Universe is teeming with galaxies, each brimming with billions of stars. Though all galaxies shine brightly, many are cloaked in dust while others are so distant that to observers on Earth they appear as little more than faint smudges. By creating comprehensive maps of even the dimmest and most-distant galaxies, astronomers are better able to study the structure of the Universe. The largest such map to date has just grown even larger, with the tenth data release from the DOE’s Lawrence Berkeley National Laboratory's Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Survey. The DESI Legacy Imaging Survey expands on the data included in two earlier companion surveys: the Dark Energy Camera (DECam) Legacy Survey and the Beijing-Arizona Sky Survey. Jointly these three surveys imaged 14,000 square degrees of the sky visible from the northern hemisphere. This ambitious six-year effort involved three telescopes, one petabyte (1000 trillion bytes) of data, and 100 million CPU hours on one of the world’s most powerful computers at the US Department of Energy’s National Energy Research Scientific Computing Center.