Astronomers using the James Webb Space Telescope have discovered complex organic molecules frozen in ice around a young star in the Large Magellanic Cloud, our nearest neighboring galaxy. This includes the first detection of acetic acid beyond the Milky Way. The finding suggests life's chemical precursors formed in early universe-like conditions.
In a groundbreaking observation, the James Webb Space Telescope (JWST) has revealed five complex organic molecules (COMs) in the ice surrounding the protostar ST6 in the Large Magellanic Cloud (LMC), located 160,000 light-years from Earth. The molecules identified are methanol, ethanol, methyl formate, acetaldehyde, and acetic acid—the latter marking its first confirmed detection in space ice outside our galaxy. Ethanol, methyl formate, and acetaldehyde were also observed in ices beyond the Milky Way for the first time. The team noted potential signs of glycolaldehyde, a sugar-related molecule tied to RNA, though confirmation is pending.
Led by Marta Sewilo from the University of Maryland and NASA, the research utilized JWST's Mid-Infrared Instrument (MIRI) and was published in the Astrophysical Journal Letters on October 20, 2025. 'It's all thanks to JWST's exceptional sensitivity combined with high angular resolution that we're able to detect these faint spectral features associated with ices around such a distant protostar,' Sewilo said. Prior to JWST, only methanol had been confirmed in protostar ices, even in the Milky Way.
The LMC's low-metallicity environment—one-third to one-half the heavy elements of our solar system—and intense ultraviolet radiation mimic early universe conditions. 'The low metallicity environment... is interesting because it's similar to galaxies at earlier cosmological epochs,' Sewilo explained. Co-author Will Rocha from Leiden University added, 'Our detection of COMs in ices supports these results,' highlighting formation on cosmic dust grains.
This discovery implies organic building blocks of life could have emerged earlier and in harsher settings than thought, potentially surviving planetary formation. Sewilo's team plans to study more protostars in the Magellanic Clouds to assess COM prevalence.