The largest galaxy survey ever confirms that the universe is not lumpy enough
Six-year results from the Dark Energy Survey highlight unresolved tensions in standard cosmological theory
The Dark Energy Survey observed approximately 150 million galaxies visible in Earth’s southern sky.
Erin Sheldon and the Dark Energy Survey Collaboration
Astronomers have released the most ambitious cosmic map yet, confirming that matter in the universe is less sticky than standard cosmological theory predicts.
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 sizes 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 brightness and other characteristics of the supernova; Clustering of galaxies in space and time; The evolving shape of the remnants of pressure waves generated in the early stages of the universe; and distortion of images of background galaxies by large concentrations of interfering invisible ‘dark matter’.
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The combined results refine previous DES measurements to confirm that gravity does not bind galaxies together, more than observations of the early universe would lead us to guess, were the standard theory of the evolution of the universe correct – an ongoing puzzle for cosmologists.
This article is reproduced with permission and was first published On 30 January 2026.
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