Interstellar Comet 3I/ATLAS Exhibits a Methanol-Rich Signature Pointing to Formation in a Distant Planetary System

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Nathan Roth says 3I/ATLAS is a fingerprint from another star system, since ALMA finds unusually high methanol and a methanol-to-HCN ratio that suggests colder birth conditions, with methanol released from both the nucleus and icy grains in the coma—the first time this pattern has been mapped in an interstellar object—discovered in July 2025 by ATLAS and only the third interstellar visitor after Oumuamua and 2I/Borisov, with ongoing ALMA, Hubble, and JWST observations tracking its coma and tail and supporting a natural icy body rather than an artificial origin.