Galaxies without dark matter perplex astronomers - Nature.com

Researchers say a cosmic collision could have created two galaxies that don’t contain the mysterious substance — but others cast doubt on the claim.

This Hubble image captures a set of galaxies that are unusual because they seem not to have dark matter.Credit: NASA/ESA/P. van Dokkum, Yale Univ. Astronomers think that galaxies cannot form without… [+4568 chars]

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