New Delhi: In a groundbreaking study, a team of Indian astronomers from the Aryabhatta Research Institute of Observational Sciences (ARIES) and Assam University has, for the first time, mapped the magnetic field “skeleton” surrounding small molecular clouds near the Milky Way disc. The research, highlighted by the Ministry of Science and Technology on Monday, March 23, 2026, provides a rare look at the invisible forces that regulate how stars are born within the cold, dense regions of our galaxy.
While gravity and internal pressure have long been recognized as the primary drivers of star formation, the magnetic field has remained a “silent player” due to its invisibility. To “see” these fields, the researchers utilized R-band polarimetry, a technique that measures the polarization of light from distant stars as it passes through the dust grains of the molecular clouds. By analyzing how thousands of these light waves vibrate in specific directions, the team was able to reconstruct the magnetic architecture of two specific clouds: L1604 and L121.
The study revealed two distinct “personalities” within these cosmic laboratories. L1604 is a highly dense and massive cloud with the potential to form numerous new stars. In contrast, L121, located closer to the galactic centre, is less massive but possesses a significantly stronger magnetic field. Crucially, the scientists found that both clouds are currently in a sub-critical state, meaning their magnetic fields are powerful enough to resist gravitational collapse across the majority of their structures.
This discovery underscores magnetism as the “invisible hand” that prevents the galaxy from consuming all its gas simultaneously. While the surrounding envelopes of these clouds remain magnetically protected, the researchers noted that gravity is quietly gaining the upper hand deep within their dense cores. These cores act as the true cradles of star birth, where the million-year-long “dance” between gravity and magnetism eventually tips in favour of creation.
