In a groundbreaking finding that may alter our comprehension of how life”s chemical components are distributed in the universe, astronomers have identified organic molecules containing more than six atoms encased in ice surrounding a young star designated ST6. This star is currently forming within a galaxy located outside the Milky Way.
Utilizing the Mid-Infrared Instrument (MIRI) on the James Webb Space Telescope (JWST), researchers discovered five distinct carbon-based compounds in the Large Magellanic Cloud, our closest neighboring galaxy. The study, led by Marta Sewilo, a research scientist at the University of Maryland and NASA, presents its findings in a paper published on October 20, 2025, in the Astrophysical Journal Letters.
The team successfully identified five complex organic molecules (COMs) in the icy environment surrounding the young protostar. Among these are methanol and ethanol, which are familiar types of alcohol, as well as methyl formate and acetaldehyde, primarily used as industrial chemicals on Earth. Additionally, they detected acetic acid, the primary ingredient in vinegar, which had never before been definitively identified in space ice. The findings also include the first detection of ethanol, methyl formate, and acetaldehyde in ices beyond the Milky Way galaxy.
The researchers also observed spectral features that may indicate the presence of glycolaldehyde, a sugar-related molecule and a precursor to more complex biomolecules like RNA components; however, further investigation is required to confirm this detection.
“The extraordinary sensitivity and high angular resolution of JWST enabled us to identify these subtle spectral features associated with the ices around such a distant protostar,” said Sewilo. “Before Webb, methanol was the only complex organic molecule that had been conclusively detected in ice around protostars, even within our own galaxy. The quality of our new observations has allowed us to extract more information from a single spectrum than ever before.”
The significance of this discovery is heightened by the challenging conditions in which the molecules were found. The Large Magellanic Cloud, situated approximately 160,000 light-years from Earth, acts as a natural laboratory for examining star formation under conditions reminiscent of the early universe. This galaxy contains about one-third to one-half of the heavy elements found in our solar system and endures considerably stronger ultraviolet radiation.
“The low metallicity environment, characterized by a reduced abundance of elements heavier than hydrogen and helium, is fascinating because it mirrors galaxies from earlier epochs in the cosmos,” Sewilo explained. “Insights gained from the Large Magellanic Cloud can help us understand more distant galaxies that existed when the universe was significantly younger. The harsh conditions provide valuable information on how intricate organic chemistry can occur in these primitive settings with fewer heavy elements like carbon, nitrogen, and oxygen available for reactions.”
Co-author Will Rocha, a researcher from Leiden University in the Netherlands, noted that COMs can form in both gas and ice on interstellar dust grains. After their formation, these icy COMs can be released into the gas phase; previous detections of methanol and methyl formate have occurred in the gas phase within the Large Magellanic Cloud. Although the specific formation process of COMs remains partially understood, chemical models and laboratory experiments suggest that reactions on the surfaces of interstellar dust grains are the primary contributors to COM production. “Our detection of COMs in ices supports these findings,” Rocha stated. “Identifying icy COMs in the Large Magellanic Cloud provides evidence that such reactions can effectively produce them even in harsher environments compared to our solar neighborhood.”
The presence of icy COMs in conditions analogous to those existing in the early universe implies that the fundamental building blocks for larger biomolecules essential for the emergence of life may have formed significantly earlier and under a wider range of cosmic conditions than previously believed. While these discoveries do not confirm the existence of extraterrestrial life, they indicate that these species could endure the evolution of planetary systems and eventually be integrated into newly formed planets, where life could potentially thrive.
Sewilo plans to extend her research to include additional protostars in both the Large Magellanic Cloud and possibly the Small Magellanic Cloud, the next closest galaxy to Earth. She aims to delve deeper into the complex chemistry of the universe. “Currently, we have only one source in the Large Magellanic Cloud and just four sources showing detection of these complex organic molecules in ices within the Milky Way. A larger sample from both galaxies is necessary to validate our initial results indicating differences in COM abundances,” Sewilo added. “However, this discovery has marked significant progress in our understanding of how complex chemistry emerges in the universe and opens new avenues for research into the origins of life.”
