Six-year results from the Dark Energy Survey highlight unresolved tensions in standard cosmological theory.
The Dark Energy Survey observed about 150 million visible galaxies in Earth’s southern sky.
Erin Sheldon and the Dark Energy Survey collaboration
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Astronomers have released the most ambitious cosmic map assembled so far, confirming that matter in the Universe is less clumped together than standard cosmological theory would predict.
From 2013 to 2019, the Dark Energy Survey (DES) team repeatedly imaged a large portion of Earth’s southern sky to collect the positions, colors, and shapes of approximately 150 million galaxies. Using a telescope at the Cerro Tololo Inter-American Observatory in Chile, the team also detected and studied more than 1,500 supernova explosions of a type that can be used to track the expansion history of the Universe.
The team analyzed four different aspects of the data: the luminosity and other characteristics of the supernovae; the grouping of galaxies in space and time; the evolutionary size of the remnants of pressure waves generated at the beginning of the Universe; and the distortion of images of background galaxies by large concentrations of invisible “dark matter.”
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The combined results refine previous DES measurements to confirm that gravity did not pack galaxies together as much as observations of the early Universe would lead us to predict, if the standard theory of the Universe’s evolution were correct – an ongoing puzzle for cosmologists.
This article is reproduced with permission and has been published for the first time January 30, 2026.
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