To Map the Universe, Astrophysicists Launch Largest Sky Survey Yet KPNO/NOIRLab/NSF/AURA/P. Marenfeld The Dark Energy Spectroscopic Instrument (DESI) is installed on the Nicholas U. Mayall 4-meter Telescope on Kitt Peak National Observatory near Tucson, AZ. Newswise — Cambridge, MA — In 1983, astrophysicists at the Center for Astrophysics | Harvard & Smithsonian(CfA) released a cosmic map using 2,400 galaxies. Now, CfA scientists are aiming to map 30 million. In the largest quest yet to map the universe, an international team of researchers is using DESI, or the Dark Energy Spectroscopic Instrument, to survey the skies. Observations officially began today, May 17, at Kitt Peak National Observatory near Tucson, Arizona; the mission will last five years with the goal of mapping 30 million galaxies.