How James Webb Telescope Reveals Magnetic Field's Role in Star Formation
The MeerKAT radio telescope captures the Milky Way’s plane in blue, cyan, and yellow, highlighting the supermassive black hole Sagittarius A* at its center. A detailed inset from NASA’s James Webb Space Telescope reveals the Sagittarius C star-forming region in red and cyan, showcasing the impact of magnetic fields. Credits: NASA, ESA, CSA, STScI, SARAO, Samuel Crowe (UVA), John Bally (CU), Ruben Fedriani (IAA-CSIC), Ian Heywood (Oxford)
Updated on: April 04, 2025 | By: Jameswebb Discovery Editorial Team
NASA’s James Webb Space Telescope (JWST) has unlocked a cosmic mystery at the heart of the Milky Way, revealing how powerful magnetic fields influence star formation in the chaotic Sagittarius C region. Building on its 2023 observations, the Webb team’s latest findings, released on April 02, 2025, showcase the telescope’s unparalleled ability to peer through cosmic dust and expose the hidden forces shaping the galactic center. Paired with breathtaking imagery from the MeerKAT radio telescope, this discovery—published in The Astrophysical Journal—offers new insights into why star birth is surprisingly rare near the Milky Way’s supermassive black hole, Sagittarius A*. Here’s what the James Webb team found and why it matters.
Solving the Star Formation Mystery in the Galactic Core
Nestled just 200 light-years from Sagittarius A*, the Sagittarius C stellar nursery sits within the Central Molecular Zone (CMZ)—a region brimming with dense gas and dust, the raw materials for stars. Yet, despite this abundance, the CMZ produces fewer stars than anticipated. “With so much gas and dust, why isn’t this a stellar factory?” asked John Bally, an astrophysicist at the University of Colorado Boulder and a key researcher on the project. The answer lies in an invisible force: strong magnetic fields.
Using Webb’s advanced near-infrared technology, scientists have now observed how these fields shape interstellar gas clouds, potentially preventing them from collapsing under gravity to form stars. This discovery marks the first direct evidence of magnetic influence on small-scale star formation in the galactic center.
A Cosmic Collaboration: Webb and MeerKAT Unite
The study combines Webb’s pinpoint infrared observations with the broader perspective of the MeerKAT radio telescope, which maps the Milky Way’s plane in vibrant blue, cyan, and yellow tones. MeerKAT’s image highlights the galaxy’s core, where a brilliant white-yellow glow pinpoints Sagittarius A*, surrounded by supernova remnants and towering filamentary structures. Within this vast scene, Webb zooms into Sagittarius C, revealing a striking tableau of red stars, gas clouds, and a bright cyan arch laced with crystalline, needle-like features.
“This partnership between Webb and MeerKAT is transformative,” said Samuel Crowe, a senior undergraduate at the University of Virginia, 2025 Rhodes Scholar, and co-leader of the study. “Webb’s infrared vision complements radio data, giving us a front-row seat to star formation in one of the galaxy’s most extreme regions.”
Peering Through Dust: Protostars and Outflows
Webb’s infrared capabilities have unveiled a wealth of detail in Sagittarius C. Researchers confirmed the presence of two massive protostars—each over 20 times the Sun’s mass—in the region’s brightest cluster, building on earlier hints from the Atacama Large Millimeter Array (ALMA). These young stars power bright outflows, jets of material blasting into surrounding gas clouds. Webb also identified five potential low-mass protostars, still cocooned in dust, and 88 shocked hydrogen gas features—signs of stellar jets colliding with their environment.
“We’ve long suspected outflows in Sagittarius C, but seeing them in infrared is a first,” Crowe explained. “It’s a thrilling step toward understanding star formation in the CMZ.”
Magnetic Fields: The Cosmic Sculptors
The 2023 Webb image of Sagittarius C revealed dozens of filamentary structures in a hot hydrogen plasma cloud. Now, Bally’s team suggests these filaments are sculpted by magnetic fields, amplified by the tidal forces of Sagittarius A*. These fields may confine plasma into tight, concentrated strands, resisting the gravitational pull that would otherwise birth stars. This could explain the region’s low star formation rate.
“Magnetic fields might be the missing piece in the galactic center’s stellar puzzle,” Bally noted. “Their influence on star formation here—and potentially in other galaxies—is an exciting frontier for future research.”
Why This Matters
The James Webb Space Telescope continues to redefine our view of the universe. By probing the Milky Way’s core, it’s not just revealing the birth of stars but also the forces that govern them. Led by NASA with partners ESA and CSA, Webb is paving the way for discoveries that deepen our grasp of cosmic evolution.
Stay tuned to JamesWebbDiscovery.com for more updates on this stellar journey!