The Atacama Large Millimeter/submillimeter Array in Chile detected unprecedented concentrations of methanol inside interstellar comet 3I/ATLAS during late 2025 observations released alongside the National Radio Astronomy Observatory. These recorded chemical volumes exceed the alcohol levels cataloged in almost every comparable icy body native to the Solar System.

“Observing 3I/ATLAS is like gathering a fingerprint from another solar system because the data expose its composition, and it overflows with methanol in a manner we do not normally see in our own neighborhood comets,” stated American University professor Nathan Roth, who led the research.

Chilean observatory tracks chemical plumes surrounding the coma

Researchers deployed the Atacama Compact Array in northern Chile during late 2025 to monitor the trajectory of the interstellar visitor as it accelerated toward the Sun. Intense solar warmth heated the frozen exterior crust of the celestial traveler. This thermal interaction triggered an eruption of dust and vapor that enveloped the core in a brilliant envelope known as a coma.

Spectroscopic analysis of the drifting particles inside this bright envelope exposed the precise molecular ingredients locked inside 3I/ATLAS. This orbital path offered scientists a rare opportunity to examine pristine volatile material manufactured around another star without launching deep-space exploration probes.

Astronomers calibrated the receiver antennas specifically to isolate the distinct electromagnetic radiation signatures emitted by methanol and hydrogen cyanide.

The Chilean instrument logged methanol-to-hydrogen cyanide ratios hovering between 70 and 120 across two distinct observation sessions. These measurements establish the interloper as one of the most alcohol-rich celestial objects ever documented by modern astronomy.