- September 08, 2025
- By Emily C. Nunez
In a distant galaxy called Makani, particles of dust were warmed by the light of newborn stars before being flung out into space by a massive starburst-driven wind. Over the next 100 million years, the dust traveled away from Makani’s center, ultimately ending up in the reservoir of hot gas —the circumgalactic medium (CGM)—around the galaxy.
A research team led by University of Maryland astronomy Professor Sylvain Veilleux used the James Webb Space Telescope to study these resilient dust particles, marking the first time that a dust infrared emission has been directly observed at such a great distance. Its study, published last month in The Astrophysical Journal, could help researchers understand how outflows of gas and dust affect the evolution of galaxies.
“Overall, these results provide the strongest evidence so far that the ejected dust of galactic winds may survive the long journey to the CGM,” Veilleux said. “Before this study, there had not been a direct detection of dust on such a large scale, and Webb was the key that made it happen.”
Astronomers study Makani, which means “wind” in Hawaiian, because it underwent a period of intense star formation that produced a strong galactic wind that carried gas and dust with it. In 2019, David Rupke Ph.D. ’04 led a study of Makani that found the first direct evidence that galactic winds play a significant role in creating the CGM.
That study focused primarily on outflows of gas, but Veilleux and his co-authors wanted to understand what was happening to the dust in the galactic wind. Though these galactic dust particles are microscopic, they are an important ingredient in the formation of planets and stars.
In the case of the Makani galaxy, Veilleux and his co-authors discovered that dust particles degraded along their windswept journey to the CGM but did not fully disintegrate, raising questions about how the dust was able to survive. The team’s next question to tackle is whether the dust can survive the journey all the way to the intergalactic medium—a journey of a million light years or more.