Astronomers have identified a unique binary star system, GPM J071507−114153, that emits mysterious radio pulses every eight minutes.
The discovery, reported in a study published in Nature Astronomy, marks the first time such signals have been linked to a white dwarf orbiting a Sun-like star.
Detecting the Eight-Minute Signal
The Murchison Widefield Array (MWA) in Australia first detected the signal in late 2024. Between December 2024 and September 2025, the MWA recorded 214 distinct pulses from the source. Researchers classified the phenomenon as a long-period transient, a category of space signals that pulsate over intervals ranging from minutes to hours.
GPM J071507−114153 Features a Sun-Like Star Companion
While researchers have identified approximately a dozen long-period transients, most known systems contain a white dwarf paired with a small, cool red dwarf. GPM J071507−114153 stands out because its companion is a G-type star, which is similar to our own Sun.
Optical observations from the W.M. Keck Observatory in Hawaii confirmed the nature of this Sun-like companion. The data showed that the larger star barely wobbles as the white dwarf orbits it, indicating the Sun-like star is significantly more massive than its partner.
Observing Storms Across 5,000 Light-Years
The white dwarf’s orbital path provided astronomers with a unique view of its companion. As the white dwarf swung behind the Sun-like star, researchers observed it passing through regions of intense magnetic activity.
She said that these radio observations allow scientists to detect stellar storms occurring 5,000 light-years away from Earth.
Frequently Asked Questions
What is a long-period transient?
It is a type of cosmic object that emits radio waves in repeating pulses, with periods lasting from minutes to hours. Unlike fast-spinning pulsars, these objects operate on a much slower schedule that astronomers are still working to categorize.
Why is this specific discovery significant?
This is the first identified system where a white dwarf—the core of a dead star—orbits a G-type, Sun-like star while producing radio pulses. Previous discoveries were largely limited to white dwarfs paired with smaller red dwarf stars.
How do scientists know the pulse comes from the white dwarf?
By using the MeerKAT telescope in South Africa to pinpoint the source and tracking the timing of the pulses, researchers observed the white dwarf moving in its orbit. The pulses arrive slightly earlier or later depending on the white dwarf’s position, confirming the source is tied to that specific object.
What is the next step for this research?
Astronomers expect to find many more of these systems using upcoming radio telescope arrays, such as the SKA Observatory. Future detections are intended to provide further insights into the life cycles and deaths of stars similar to our Sun.
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