Astronomers using the James Webb Space Telescope (JWST) have detected water vapor and silicate dust surrounding IRS 3, a dying star located just 0.55 light-years from Sagittarius A*, the Milky Way’s central supermassive black hole. The discovery, detailed in Astronomy & Astrophysics, confirms that stellar material can persist even within intense radiation environments.
Water and Dust Near Sagittarius A*
For years, the region immediately surrounding the Milky Way’s supermassive black hole, Sagittarius A*, was considered too hostile for the survival of complex molecular material. However, recent observations by an international team of researchers utilizing the James Webb Space Telescope’s Mid-Infrared Instrument (MIRI) have challenged this assumption. The team focused their study on IRS 3, a highly evolved star situated a mere 0.55 light-years from the galactic center.
The data reveals that IRS 3 is actively shedding its outer layers through powerful stellar winds, creating a sprawling, shell-like envelope of cosmic dust that extends approximately 10,000 astronomical units (AU) from the star. Within this envelope, astronomers identified clear spectral signatures of water and oxygen-rich silicate dust. This finding suggests that even in extreme environments dominated by intense radiation, aging stars continue to act as vital chemical factories.
The Chemical Identity of IRS 3
Previous studies had suggested that IRS 3 was a carbon-rich star, but the high-resolution spectral data from the JWST has provided a more precise classification. By collecting a continuous mid-infrared spectrum, researchers were able to confirm the presence of silicate dust composed of silicon and oxygen, identifying the star as oxygen-rich.
The research team, which included scientists from the University of Cologne, utilized advanced simulation models to map the structure of the star’s dusty envelope. These models indicate a layered, shell-like configuration where temperatures drop drastically from roughly 1,200 kelvins near the star to approximately 100 kelvins at the outer edges of the envelope.
Implications for Galactic Evolution
The survival of water in such close proximity to a supermassive black hole carries significant implications for our understanding of the galactic life cycle. Stars in the asymptotic giant branch (AGB) phase, like IRS 3, are known for enriching the cosmos with dust that eventually forms the building blocks for new celestial objects. The ability of IRS 3 to maintain this process despite the gravitational and radiative forces of Sagittarius A* demonstrates the resilience of stellar chemical enrichment.
According to the findings, IRS 3 is estimated to be approximately 72 million years old with a mass roughly six times that of the Sun. While it currently shines 60,000 times brighter than our own star, it is expected to eventually evolve into a white dwarf. The study confirms that even in the most extreme regions of the galaxy, the process of star-stuff
production—a term famously associated with Carl Sagan—remains an active and persistent feature of the universe.
Research Context and Methodology
The observations were published in the journal Astronomy & Astrophysics on August 11, 2026. To achieve these results, the team combined spectral data from the JWST’s Near-Infrared Camera (NIRCam) and the Mid-Infrared Instrument (MIRI). This multi-instrument approach allowed the researchers to reconcile their observations with theoretical models across various chemical compositions and temperatures.
Florian Peißker, an astrophysicist at the University of Cologne and lead author of the study, emphasized the significance of observing stars in these specific conditions.
The research concludes that the star’s dust production remains remarkably resilient,
ensuring that chemically rich material continues to circulate even within the inner parsec of the Milky Way.
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