Astronomers have observed a rare Einstein Cross with a bright central fifth image, produced by gravitational lensing of the distant galaxy HerS-3 (11.6 billion light-years away). Observations with NOEMA (IRAM, France), ALMA, VLA, and Hubble show that the five-image configuration can only be explained by a massive dark matter halo in the foreground galaxy group.
This discovery provides a unique laboratory to study dark matter and galaxy evolution in the early Universe, and represents the first Einstein Cross detected at sub-millimeter and radio wavelengths. The results are published in the Astrophysical Journal.
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Image: Einstein-Cross-NOEMA-IRAM-2025 (C)IRAM