Decoding the Chemistry of Star Formation
Astronomers have successfully mapped a diverse array of chemicals within the disks surrounding young stars. By utilizing the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, the COMPASS (Complex Organic Molecules in Protostars with ALMA Spectral Surveys) project has gained significant ground in identifying the building blocks that may eventually lead to the development of planets and life.
As Maria Drozdovskaya, an astrophysicist at the University of Bern and head of the COMPASS team, explained: «Our work provides insight into the complex chemistry of young star systems and is ultimately an important piece of the puzzle in understanding the origin of life.»
The Role of Methanol
Central to this research is methanol (CH3OH), which is recognized as the most abundant complex organic molecule in interstellar space. Its prevalence makes it an ideal subject for tracking how hydrogen atoms are swapped with deuterium, a heavier isotope. The ratio of these isotopes provides researchers with a chemical signature that reveals the specific environmental conditions present during the birth of a planetary system.
In a notable finding, the team detected a deuterium-rich methanol molecule in the disk of IRAS 4A2, a protostar situated roughly 1,000 light-years away in the Perseus Molecular Cloud.
Discovery of Methanol Masers
Beyond tracking isotopes, the team identified methanol maser emission—a natural microwave amplification process—in over half of the eleven protostars studied. While such emissions have been observed previously in turbulent, high-mass star systems, this marks the first time they have been detected around calmer, low-mass stars.
«The fact that it has now also been found in a low-mass protostar shows that locally extreme physical conditions can prevail there analogously to massive stars and challenges our previous understanding of the formation of sun-like stars,» added Drozdovskaya.
Future Implications and Research
The observation of these masers suggests that the underlying physical processes in star and planet formation may be universal, regardless of the star's mass. Thermal bursts occurring as a star gathers surrounding gas could potentially trigger the shocks necessary to stimulate these masers.
While the COMPASS project has identified variations in the presence of oxygen- and nitrogen-based molecules across different systems, many mysteries regarding the evolution of these chemical environments persist. The team intends to continue their analysis over the coming years, with plans to supplement their ALMA findings with data from the James Webb Space Telescope (JWST). The initial findings have been detailed in a series of seven papers featured in the October 2026 issue of the journal Astronomy & Astrophysics.