magnetar unusual radio signals
Artist’s impression of the magnetar.. Image Credit: Carl Knox, OzGrav/Swinburne University of Technology.

Astronomers Detect Unusual Radio Signals From Nearby Magnetar That Are ‘Behaving in Complex Ways’

Astronomers operating the CSIRO’s Parkes radio telescope in Australia say they have detected unusual radio signals from Earth’s closest magnetar that are “behaving in complex ways.”

A previous dormant star with a powerful magnetic field, XTE J1810-197, is only 8,000 light years away, making it the closest such star to Earth. However, unlike a typical magnetar that emits polarized light, this magnetar appears to be sending out radio waves that are circularly polarized. That means the light appears to spiral as it moves through the universe. Such a discovery was not only unexpected; a press release announcing the discovery said, “It is totally unprecedented.”

​”Unlike the radio signals we’ve seen from other magnetars, this one is emitting enormous amounts of rapidly changing circular polarization,” said Dr. Marcus Lower, a postdoctoral fellow at Australia’s national science agency – CSIRO, and the leader of the research effort. “We had never seen anything like this before.”

magnetar unusual radio waves
Murriyang, CSIRO’s Parkes radio telescope beneath the Milky Way. Image Credit: Alex Cherney/CSIRO.

The study’s co-author, University of Sydney’s Dr. Manisha Caleb, agrees, noting that the readings don’t match any previous radio signals coming from magnetars. In fact, they don’t even match theoretical models that try to predict the behavior of various cosmological phenomena.

​”The signals emitted from this magnetar imply that interactions at the surface of the star are more complex than previous theoretical explanations,” Caleb explained.

Deepening the mystery behind the unusual radio signals is the fact that simply detecting any type of radio emission from a magnetar is extremely rare. According to the researchers who spotted the signals coming from XTE J1810-197, it is only one of a handful of magnetars astronomers have found that emit radio waves.

Further adding to the mystery is the fact that the signals were first detected back in 2003 before they suddenly went silent. Then, in 2018, astronomers using the University of Manchester’s 76-m Lovell telescope at the Jodrell Bank Observatory saw that the signals had returned. That data was quickly followed up by Murriyang, the CSIRO instrument that detected these most recent signals.

While there is no immediate explanation for the cause of the unusual radio signals, the researchers say that their complex behavior has led to an equally unusual theory.

​“Our results suggest there is a superheated plasma above the magnetar’s magnetic pole, which is acting like a polarising filter,” Dr. Lower said. Still, the researcher admits it is only a theory, and concedes that explaining how exactly the plasma is doing this “is still to be determined.”

Follow-up studies will likely be required to answer the mystery behind the complex and unusual radio waves coming from Earth’s closest magnetar. Fortunately, the researchers note that the 64-meter diameter telescope is equipped with “a cutting-edge ultra-wide bandwidth receiver” that is perfect for the job.

magnetar unusual radio waves
Murriyang, CSIRO’s Parkes radio telescope. Image Credit: CSIRO/Red Empire Media.

“The receiver allows for more precise measurements of celestial objects, especially magnetars,” the researchers explain, “as it is highly sensitive to changes in brightness and polarisation across a broad range of radio frequencies.

While it may be a long time before we know conclusively what is behind the unusual radio signals, the researchers behind this latest discovery, which is published in the journal Nature Astronomy, say that studying magnetars is crucial to understanding a great many mysteries of the universe.

“Studies of magnetars such as these provide insights into a range of extreme and unusual phenomena,” the release explains, “such as plasma dynamics, bursts of X-rays and gamma-rays, and potentially fast radio bursts.”

 Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at, or email him directly at