The comet 3I/ATLAS is just the third visitor from beyond our Solar System that humanity has ever observed.

Interstellar comet, 3I/ATLAS, might be one of the oldest celestial bodies ever seen, potentially forming 10 to 12 billion years ago. This ancient visitor, detected in July 2025,…

Carbon isotopic measurements of the interstellar comet 3I/ATLAS reveal that it may have formed as long ago as 12 billion years and thus represents a preserved fragment of an…

The evidence is mounting: this interstellar visitor is even older and weirder than anyone thought