Dark energy survey DESI creates largest 3D map of the universe

Must ReadScience & TechnologyDark energy survey DESI creates largest 3D map of the universeBy Web Desk-Apr 17, 2026The Dark Energy Spectroscopic Instrument (DESI) has produced the largest high-resolution 3D map of the universe. Over five years, it observed more than 47 million galaxies and quasars, along with 20 million stars. Researchers will now analyze this extensive dataset to explore the nature of dark energy. Mounted on the Nicholas U Mayall 4-m Telescope at Kitt Peak National Observatory in Arizona, DESI, which began collecting data in 2021, uses 5000 robot-controlled optical fibers connected to spectrographs. This setup enables DESI to map galaxies and quasars comprehensively, with spectroscopic data indicating how fast galaxies recede from us based on redshift. By studying galaxy clustering in the past versus today, scientists aim to understand dark energy’s effects. A 2024 publication indicates that the universe’s expansion rate is not constant. DESI will use the expanded dataset to further investigate whether the “cosmological constant” may be changing, with results expected to be published next year. Michael Levi, the DESI director based at the Lawrence Berkeley National Laboratory, expressed his enthusiasm, calling the survey “incredibly exciting” and “spectacularly successful.” “The instrument performed better than anticipated,” he states. “We’re going to celebrate completion of the original survey and then get started on the work of churning through the data, because we’re all curious about what new surprises are waiting for us.” DESI will continue its observations until 2028 and expand the map by approximately 20% to include parts of the sky that are more difficult to observe.