New astronomical observations suggest "supergalaxies," the largest galaxies in the universe, are born of cosmic clouds of cold gas. Previously, scientists believed supergalaxies were formed by merging galaxies at the center of galactic clusters.

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New astronomical observations suggest "supergalaxies," the largest galaxies in the universe, are born of cosmic clouds of cold gas. Previously, scientists believed supergalaxies were formed by merging galaxies at the center of galactic clusters.