The new observations provide the most detailed mid-infrared view yet of the highly evolved star IRS 3, which is located just 0.55 light-years from Sagittarius A*, the Milky Way galaxy's central supermassive black hole. IRS 3 has reached a stage near the end of its life called the asymptotic giant branch phase. Stars in this phase of life are huge, cool, and luminous, and they shed gas into space with their powerful stellar winds. This cast-off stellar material is one of the most important sources of cosmic dust, but it was not clear if it could be produced by a star so close to a supermassive black hole.

By analysing the star’s infrared light with Webb’s MIRI (Mid-Infrared Instrument), the research team identified clear signatures of oxygen-rich dust and, for the first time, detected water in the star’s surrounding envelope. The results show that even under the harsh conditions near a supermassive black hole, evolved stars like IRS 3 can still produce dust and other materials important for the creation of future generations of stars and planets.

“Galactic centres are among the most extreme environments, so understanding whether stars can continue enriching their surroundings there is an important question,” said lead author Florian Peißker of the University of Cologne in Germany. “With Webb, we can directly observe how stars behave under these conditions and see that dust production remains remarkably resilient.”