Located a few hundred light-years from Sagittarius A*, the supermassive black hole at the galaxy's core, Sagittarius B2 contains immense reservoirs of gas and dust. Webb's infrared vision allows astronomers to penetrate much of this material, exposing young stars, heated dust, and stellar nurseries otherwise hidden from view.

The Mid-Infrared Instrument (MIRI), managed by NASA's Jet Propulsion Laboratory, revealed glowing dust heated by very young massive stars, while NIRCam imagery highlighted clusters of colorful stars. Comparing the two instruments shows the dramatic contrast between the longer mid-infrared wavelengths, which emphasize dust and gas, and shorter near-infrared wavelengths that favor starlight.

"Webb's powerful infrared instruments provide detail we've never been able to see before, which will help us to understand some of the still-elusive mysteries of massive star formation and why Sagittarius B2 is so much more active than the rest of the galactic center," said astronomer Adam Ginsburg of the University of Florida, principal investigator of the program.

Not all regions yielded to Webb's gaze. Some of the darkest patches in the images are areas so densely packed with cold gas and dust that even infrared light cannot escape. These cocoons serve as the raw material for future stars, sheltering those too young to emit visible light.

Sagittarius B2 North, the reddest area in MIRI's view, emerged in striking clarity. Known as one of the most molecule-rich environments in the galaxy, it had never been seen at this resolution. The data are expected to refine models of star birth and the chemical complexity of the galactic center.

Despite the vast gas supplies in the Milky Way's core, star formation there is relatively subdued. Sagittarius B2 is an exception, producing half of the galactic center's stars despite holding only a tenth of its gas. Researchers hope Webb will help explain why this region is so anomalously fertile and whether star production has been continuous for millions of years or triggered by more recent processes.

"Humans have been studying the stars for thousands of years, and there is still a lot to understand," said Nazar Budaiev, a graduate student at the University of Florida and co-principal investigator of the study. "For everything new Webb is showing us, there are also new mysteries to explore, and it's exciting to be a part of that ongoing discovery."

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