An interstellar comet that blazed past the Sun last year could be nearly three times older than our Solar System and is unlike anything ever before seen in our cosmic backyard, astronomers said Monday.

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,…

All signs were already indicating that interstellar comet 3I/ATLAS was unlike anything we'd ever seen.

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