Astrophysicists have discovered ILT J110160.52+552119.62, a recently discovered temporary radio source, and that the arrival of that approximately one minute pulse with a periodicity of 125.5 minutes is a red-white, white-white dwarf binary system with orbital periods that match the orbital period observed when two stars are observed when they are engaging.
Artistic illustration showing radioactive pulses emitted by the binary star system: white d star orbit around a red d star. Image credits: Daniëlle Futselaar/Artsource.nl.
In recent years, astronomers have detected radio pulses from sources in the Milky Way that last from seconds to minutes.
These pulses differ from what you would expect from known pulsars that produce pulses on the order of milliseconds.
Furthermore, unlike radiopulsars, these so-called long-term transients (LPTs) are periodic on timescales ranging from minutes to hours.
There have been some hypotheses regarding the origin of these novel pulses, but evidence is scarce.
“There are several highly magnetized neutron stars or magnetores known to exhibit radio pulses in periods of a few seconds,” said Charles Kilpatrick, a northwestern astrophysicist.
“Some astrophysicists also claim that the source is spinning and can emit pulses at regular time intervals, so radio emissions are only shown when the source rotates towards us.”
“I know now that at least some long-term radio transients come from binary.”
“We hope this motivates radio astronomers to localize new classes of sources that could arise from neutron stars or magnetoresistance binaries.”
In their study, Dr. Kilpatrick and colleagues focused on periodic radio signals from transient radio sources designated as ILT J110160.52+552119.62 (ILT J1101+5521);
New imaging techniques were used to detect some of these radio pulses in data collected by low frequency arrays (LOFAR).
Behaving like a large radio camera, the telescope can pinpoint the exact location of the radio source in the sky.
According to the team, the Object is about 1,600 light years away in the Ursa major's constellation.
Follow-up observations with multiple mirror telescopes of 6.5 m diameter in Arizona and the Texas Hobby and Everly telescope showed that the ILT J1101+5521 is not a single flashing star, but two stars that cause pulses together.
A white dwarf in orbit around the two stars, the red war star, brings a common center of gravity into orbit every 125.5 minutes.
Researchers say there are two possibilities for the way stars produce unusually long radio pulses.
Potentially, radio bursts can be emitted from the strong magnetic field of a white dwarf or generated by the interaction of a white dwarf and its stellar companion magnetic field.
However, further observation is required to make this clear.
“Thanks to this discovery, we know that compact objects other than neutron stars can produce bright radio emissions,” says Dr. Kaustub Rajwade, an astronomer at Oxford University.
Discoveries are reported in a paper It's published in the journal today Natural Astronomy.
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I. de Ruiter et al. Sporadicated radio pulses from white dwarf binaries during orbit. Nut AthlonPublished online on March 12, 2025. doi:10.1038/s41550-025-02491-0
Source: www.sci.news
