On January 10, 2025, an international team of researchers announced a groundbreaking discovery regarding cosmic jets, revealing the first concrete evidence of a universal mechanism that shapes and stabilizes these powerful streams of matter and energy in the universe.
Cosmic jets, which can reach velocities near the speed of light, originate from various sources, including supermassive black holes and protostars within our Milky Way. Despite their diverse energy sources, scientists believe that these jets play a crucial role in the evolution of their surrounding environments, representing different expressions of a singular universal phenomenon.
The mystery of how these jets remain collimated—focused without dispersing into space—has puzzled scientists for decades. However, a study published in the Astrophysical Journal Letters has provided a solution, presenting clear evidence of a helical magnetic field, resembling a spiral spring, within a protostellar jet.
This discovery, based on observations from the National Radio Astronomy Observatory (NRAO) in the United States, supports the notion that the collimation mechanism of jets is universal across different astrophysical environments. Guillem Anglada, a researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC), noted, "This study required long integration times and a complex data calibration process, pushing the observatory to its limits."
Utilizing the high sensitivity and broad bandwidth of the upgraded observatory, the team conducted an unprecedented analysis of the rotation measure of synchrotron radiation from the jet known as HH 80-81, originating from a young star in our galaxy. This analysis allowed researchers to measure the rotation of the polarization angle of the radiation as it traversed a magnetized and ionized medium, revealing the true orientation of the magnetic field.
The confirmation of a helical magnetic field, akin to those found in cosmic jets produced by supermassive black holes in distant active galaxies, marks the first clear evidence that jets from young stars and those from far-off galaxies share the same collimation process. Anglada emphasized, "This discovery enhances our understanding of the fundamental processes governing the flows of matter and energy in the universe."