The DESI Legacy Imaging Surveys have released the largest-ever 2D color map of the universe, combining 263,407 telescope exposures to create a 5.6-trillion-pixel image containing nearly 4 billion celestial objects. Covering roughly 75% of the sky in visible and near-infrared light, the map is publicly available through the Legacy Survey Sky Viewer.

Astronomers and citizen scientists can use the map to explore the cosmos, search for rare phenomena like gravitational lenses and supernovae, and investigate mysteries such as dark matter and dark energy. The 2D map serves as the foundation for the Dark Energy Spectroscopic Instrument (DESI) survey, which builds a 3D map to study dark energy's evolution over time.

More than 160 scientists contributed to the project, with a team of 20 producing the final dataset. The map was compiled using data from three ground-based surveys and NASA's WISE satellite, processed on the Perlmutter supercomputer at NERSC. Early DESI results from April 2026 hinted that dark energy's impact may be weakening.

The Legacy Surveys map will guide DESI operations and support future observatories like the Vera C. Rubin Observatory and NASA's Nancy Grace Roman Space Telescope. It will also help train AI tools for analyzing vast amounts of astronomical data.