Plate Nº 97 · recorded November 14, 2026
Space & AstronomyReported finding
Eight-Minute Radio Pulse Traced to White Dwarf 5,000 Light-Years Away
A white dwarf spinning every eight minutes beams radio pulses from 5,000 light-years away, letting astronomers watch its orbit and even spot storms on its sun-like companion star.
By Nathan Brooks3 min read698 words
In brief
- The system GPM J071507−114153 lies about 5,000 light-years away and its white dwarf spins once every eight minutes.
- The research was published in Nature Astronomy on Nov. 12.
- Only around a dozen long-period transients have been found since the first was detected in 2021.
- Keck Observatory confirmed the companion is a G-type star, the same class as the sun.
- MeerKAT and the MWA are precursor telescopes for the Square Kilometre Array project.
A dead star spinning once every eight minutes is firing radio pulses toward Earth from roughly 5,000 light-years away — and for the first time, astronomers can see it moving in its orbit. The system, designated GPM J071507−114153, pairs a white dwarf with a sun-like companion, and researchers say pinning the pulses to the white dwarf's neighborhood could solve a four-year-old mystery about a rare class of cosmic radio sources.
The findings appeared Thursday, Nov. 12, in the journal Nature Astronomy.
What makes this system an odd couple?
A white dwarf is the dense leftover core of a star that has burned through its fuel — imagine something with roughly the mass of the sun squeezed into a body the size of Earth. In this binary, the white dwarf whips around its orbit every eight minutes while a G-type star, the same spectral class as our sun, keeps it company.
That pairing is unusual. Astronomers have seen radio pulses from binaries before, but almost always with red dwarfs — smaller, cooler stars — as the companion. Systems like GPM J071507−114153, with a sun-like star in the mix, are rare.
What are long-period transients?
GPM J071507−114153 belongs to a class of objects called long-period transients, or LPTs. These sources emit radio signals that switch on and off over intervals of minutes or hours. Astronomers have detected only around a dozen of them since the team behind this research discovered the first one in 2021.
Several known LPTs contain a white dwarf plus a companion star. The problem: nobody could tell which of the two stars was actually generating the pulses. That ambiguity has clouded the field's understanding of what LPTs fundamentally are.
How did the team crack the case?
The breakthrough came from the clarity of the signal itself. "This is the first time the pulses are clear enough to see the white dwarf moving in its orbit around its companion," said team leader Sam McSweeney, a commissioning scientist with the Square Kilometre Array Observatory (SKA). "So we know that the pulsations are coming from a region close to the white dwarf, or possibly even from the white dwarf itself."
The detection chain spanned three continents. Natasha Hurley-Walker of the International Centre for Radio Astronomy Research (ICRAR) at Curtin University in Australia said the team first spotted the system in a large survey using the Murchison Widefield Array (MWA), which scans the entire Milky Way visible from Australia. South Africa's MeerKAT radio telescope then nailed down its precise position. Finally, the W.M. Keck Observatory on Maunakea in Hawaii confirmed the find in visible light — and verified that the companion star is a G-type star, just like the sun.
What did the pulses reveal beyond the white dwarf?
The data carried a bonus: evidence of stellar weather. "As a bonus, we also saw the white dwarf moving behind a region with a strong magnetic field, most likely a 'stellar prominence,' which is a large loop of plasma erupting from a star's surface," Hurley-Walker said. The pulses also let the team detect flares erupting on the sun-like star itself.
"It's amazing that by using radio wavelengths we can detect the storms on a star over 5,000 light-years away," she added — a distance of roughly 30 million times the gap between Earth and the sun.
Why does this matter for future telescopes?
Both the MWA and MeerKAT are precursors to the Square Kilometre Array, the world's largest and most sensitive radio telescope project now under construction. McSweeney argues the discovery is a preview of what's coming.
"If we are already making such discoveries with precursor telescopes, just imagine how many more star systems we will be able to find, and what a beautifully detailed view of their signals we will have, once the SKA telescopes are completely built," he said.
With only about a dozen LPTs known since 2021, the catalog is small. Preliminary as the field may be, the new result narrows the search: the radio heartbeat of at least one LPT now points squarely at its white dwarf.
via space.com (Source)
More from Nathan Brooks
Show full bio
Market editor covering companies, deals and strategy in general science news at SciBeat.
355 articles
Nearby plates
- Dead Star Fires Radio Pulse Every Eight Minutes, and a Sun-Like Star Answers
- Radio Pulses Every 7.9 Minutes Trace Storms on a Sun-Like Star
- Zombie Star Pulses Every 7.9 Minutes, and a Sun-Like Star May Be Why
- Astronomers Find Youngest White Dwarf Paired With a Millisecond Pulsar
- Dead Star With Two Debris Rings May Preview Our Solar System's End