Interstellar comet 3I/ATLAS shows unique chemical composition

Astronomers have identified unique chemical signatures in the interstellar comet 3I/ATLAS, suggesting it originated in an environment significantly different from our Solar System. Observations using the William Herschel Telescope revealed a plasma tail unusually rich in molecular nitrogen. Based on the ratio of nitrogen to carbon monoxide, researchers estimate the object formed at temperatures below -240°C, approximately 30 degrees above absolute zero.

Data from the ALMA radio telescope further highlighted an exceptionally high concentration of methanol. The ratio of methanol to hydrogen cyanide was measured at approximately 79 and 124, placing 3I/ATLAS among the most methanol-rich comets studied to date. Researchers also detected five types of charged particles in the tail: N₂⁺, CO⁺, CO₂⁺, H₂O⁺, and CH⁺, a combination not previously recorded for an interstellar object.

Nathan Roth of American University, who led the study, noted that observing 3I/ATLAS is akin to taking a fingerprint from another planetary system. The comet is currently traveling on an open hyperbolic orbit and will return to interstellar space after passing through the Solar System.