Indian Institute of Space Science and Technology (IIST), Thiruvananthapuram astronomers have made a remarkable breakthrough in the study of how masses of stars are formed, discovering a high-altitude set image—the circular polarization in radio waves coming out of a very young protostar at 4,500 light-years distance in the sky.
This discovery revolves around a huge protostar in the Milky Way galaxy called IRAS 18162-2048, which is the earliest phase of star formation known to us. In this stage the star under development keeps gaining more gas and dust all around itself but, on the other hand, exploding high-velocity materials in opposite ways via bipolar jets.
The remarkable fact about the discovery is that circular polarization in the radio emissions has also been observed, which is the phenomenon when electromagnetic waves move in a circular motion through the space. This technically challenging signature gives scientists the first direct way to determine the strength of the magnetic field in close proximity to a forming massive star.
This PHD student (Amal George Cheriyan) of Professor Sarita Vig at IIST made these observations at the National Radio Astronomy Observatory (NRAO), Karl G. Jansky Very Large Array, USA. Their results have already appeared in the Astrophysical Journal Letters, thus being a great milestone in astrophysical studies.
The object being studied is one of the few sources of powering in our galaxy the largest and brightest known protostellar jets (HH80-81). Magnetic fields and rotation in protostellar systems have long been thought to power these strong jets, and direct evidence has so far been impossible to achieve with massive protostars.
Past observations have managed to identify powerful magnetic fields in low-mass protostars, which later create planets similar to our Sun. Nevertheless, massive protostars that grow into the biggest stars over 8 to 10 solar masses pose new problems to the researchers.
The circular polarization signals from these objects are exceptionally faint and sporadic, making detection extraordinarily difficult. Professor Nirupam Roy from the Indian Institute of Science in Bengaluru emphasized the rarity of this achievement, noting that detecting circular polarization is challenging even in active galactic nuclei, where extreme conditions are better understood.
The fact that researchers observed this phenomenon in a massive protostar environment, buried within dense gas and dust, makes the result particularly remarkable.The new data has enabled scientists to calculate the magnetic field strength near the protostar at approximately 20-35 Gauss, roughly 100 times stronger than Earth’s magnetic field. These measurements align closely with observations from low-mass protostars, suggesting a common magnetic origin across different stellar formation processes.
This discovery provides compelling evidence for a universal jet-launching mechanism, supporting the long-standing theory that powerful jets from both stars and black holes operate through the same magnetic engine. The detection of circular polarization strengthens the case that jet formation physics remains consistent across various astrophysical environments.
The research collaboration extended beyond India, involving scientists from the Institute of Radio Astronomy and Astrophysics of Mexico’s National Autonomous University and the Instituto de Astronomía Teórica y Experimental of Argentina’s Universidad Nacional de Córdoba.
This breakthrough represents more than just a technical achievement in radio astronomy. It opens new avenues for understanding how massive stars form and evolve, processes that ultimately shape entire galaxies. Massive stars play crucial roles in cosmic evolution, producing heavy elements through nuclear fusion and distributing them throughout the universe when they eventually explode as supernovae.
The fact that a polarized beam of the massive protostar was successfully detected reflects the rising potential of contemporary radio astronomy and the collaboration of international scientists. With the advance in technology, the researchers expect to unravel further mysteries regarding the formation processes of stars that have been buried for billions of years.
The significance of this finding is a recognition of the increasing role of India in research in space science and the greater need to continue the investment in astronomical infrastructure and education. The research work done by the IIST researchers adds to the worth of knowledge in the universal scientific community, which furthers the knowledge on the great cosmic processes involved in the formation of stars in the universe.
