Astronomers suggest comet 3I/Atlas, the third observed interstellar visitor, may be up to 12 billion years old, predating our solar system. Its unique chemical composition, detected by the James Webb telescope, indicates formation in a very cold environment, unlike any known solar system body.
A new analysis suggests interstellar comet 3I/ATLAS could be 7 billion years old, potentially making it older than our Solar System. Discovered in July 2025, its unusual features initially sparked speculation about artificial origins, but the Oxford model points to an ancient natural object from the Milky Way's thick disk.
The James Webb Space Telescope has detected methane within interstellar comet 3I/ATLAS, a finding that challenges existing comet science. The comet also shows an unusual dominance of carbon dioxide and an uneven decline in gas release as it moves away from the Sun, suggesting formation under different conditions than solar system comets.
