New research provides the first conclusive evidence that a fast radio burst can originate from the magnetosphere, the highly magnetic environment immediately surrounding an extremely compact object.
An artist’s impression of a neutron star. Image credit: Sci.News.
Fast radio bursts (FRBs) are brief and brilliant explosions of radio waves that originate mostly from extragalactic distances.
These events emit as much energy in one millisecond as the Sun emits in 10,000 years, but the physical phenomenon that causes them is unknown.
Theories range from highly magnetized neutron stars, blasted by gas streams near to a supermassive black hole, to suggestions that the burst properties are consistent with signatures of technology developed by an advanced civilization.
In new research, MIT astronomer Kenzie Nimmo and colleagues focused on an event named FRB 20221022A.
The burst was first detected by the Canadian Hydrogen Intensity Mapping Experiment (CHIME) in 2022.
The event occurred in a galaxy about 200 million light-years away and lasted about two milliseconds.
The new study suggests FRB 20221022A emerged from a region that is extremely close to a rotating neutron star, 10,000 km away at most.
At such close range, the burst likely emerged from the neutron star’s magnetosphere — a highly magnetic region immediately surrounding the ultracompact star.
“In these environments of neutron stars, the magnetic fields are really at the limits of what the Universe can produce,” Dr. Nimmo said.
“There’s been a lot of debate about whether this bright radio emission could even escape from that extreme plasma.”
“Around these highly magnetic neutron stars, also known as magnetars, atoms can’t exist — they would just get torn apart by the magnetic fields,” added MIT astronomer Kiyoshi Masui.
“The exciting thing here is, we find that the energy stored in those magnetic fields, close to the source, is twisting and reconfiguring such that it can be released as radio waves that we can see halfway across the Universe.”
The findings appear in the journal Nature.
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K. Nimmo et al. 2025. Magnetospheric origin of a fast radio burst constrained using scintillation. Nature 637, 48-51; doi: 10.1038/s41586-024-08297-w
