Ninety percent of the mass in this cluster is dark matter. Gravity makes dark matter clump together, but dark energy counteracts this effect. Studying the density of dark matter across the cosmos will help astronomers learn how dark energy influences the structure of our universe. The telescope’s sensors make it like a net for light, Dr. Cuillandre said. “It’s very rare to find an isolated galaxy,” Dr. Cuillandre said.

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Persons: Euclid, Katrina Miller Euclid, ” Jean, Charles Cuillandre, Beta, Cuillandre, ”, Michael Seiffert, “, We’re, Seiffert Organizations: European Space Agency, CEA Paris, Jet Propulsion Laboratory, Messier