DESI at the Mayall Telescope (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption The Dark Energy Spectroscopic Instrument (DESI), shown in this illustration, will be mounted on the 4-meter Mayall telescope at Kitt Peak National Observatory near Tucson, Ariz. It will collect data on light from 35 million galaxies and quasars to make the biggest 3-D map of the universe ever. Credit R. Lafever, J. Moustakas/DESI Collaboration Usage Restrictions None 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.