Updated

Updated · BBC Science Focus · Jun 14

Sydney Scientists Trace 1 Long-Period Radio Transient to Binary Star ASKAP J1745−5051

Updated

Updated · BBC Science Focus · Jun 14

Sydney Scientists Trace 1 Long-Period Radio Transient to Binary Star ASKAP J1745−5051

Q: How will this 'stellar Rosetta Stone' help astronomers decode a dozen other mysterious radio signals that have long baffled science?

It gives astronomers a verified template: one long-period radio transient is now firmly tied to a close white-dwarf–red-dwarf binary, with a known physical mechanism behind its bursts. In ASKAP J1745−5051, the radio flashes are produced when the two stars’ magnetic fields interact at specific points in their 82-minute orbit, while X-rays come from hot material pulled onto the white dwarf. Because the radio and X-ray signals are both linked to the orbit but peak at different times, astronomers now have a detailed map of how orbital motion, accretion and magnetism combine to create these transients. That matters because the other dozen LPTs have been hard to classify. Some were thought to be ultra-slow pulsars or magnetars, but those models have struggled to explain their long periods and sustained emission. ASKAP J1745−5051 provides observable markers astronomers can now search for in other sources: periodic bursts tied to an orbit, polarized coherent radio emission, frequency drift, intermittency, optical signs of an accreting white dwarf system, and possible X-ray counterparts. If other LPTs show the same pattern, they can be identified as related white-dwarf binaries rather than neutron-star systems. If they do not, astronomers can separate them into different classes, including pulsars. In that sense, the system acts like a Rosetta Stone: it translates a previously mysterious signal into a physical model that can be tested across the Milky Way.

3 articles · Updated · BBC Science Focus · Jun 14

ASKAP J1745−5051 links one of the Milky Way’s mysterious long-period radio transients to a tight binary containing a white dwarf and a red dwarf, University of Sydney researchers reported in Nature Astronomy.
Just over a 1-hour orbit appears to drive the signal: magnetic interactions between the two stars produce radio bursts at specific orbital points, creating regular repeating emissions.
About 1/10 the Sun’s mass, the red dwarf also sheds material onto the white dwarf, heating it and producing X-rays alongside the radio signal.
Around a dozen long-period radio transients have been detected across the Galaxy, and the team said this system could serve as a “stellar Rosetta Stone” for sorting whether others resemble pulsars or white-dwarf binaries.
Sussex University astronomer Darren Baskill said the observations make the radio-wave source look solved, though key questions remain about the underlying physics of cataclysmic variable stars.

Sources

BBC Science Focus1d ago

University of Sydney Scientists Identify Binary Star System ASKAP J1745−5051 as Source of Long-Period Radio Transients

Yahoo New Zealand News1d ago

Astronomers might have decoded a mysterious signal from space - Yahoo

The National Tribune1d ago

Student astronomer discovers 'Rosetta stone' for mysterious cosmic signals | The National Tribune

How will this 'stellar Rosetta Stone' help astronomers decode a dozen other mysterious radio signals that have long baffled science?

What fundamental secrets of extreme physics might this unique 'natural laboratory' in space unlock that we can't replicate on Earth?

ASKAP J1745−5051: How a Cataclysmic Variable Shattered the Neutron Star Paradigm for Long-Period Radio Transients

Overview

In June 2026, astronomers made a groundbreaking discovery with ASKAP J1745−5051, the first confirmed source of long-period radio transients (LPTs) that is not a neutron star. This system, classified as a cataclysmic variable, consists of a strongly magnetized white dwarf and a low-mass red dwarf companion locked in a tight orbit. The finding challenges long-held beliefs about the origins of these mysterious cosmic signals and opens new directions for research. ASKAP J1745−5051’s unique properties are reshaping our understanding of LPTs and highlighting the diversity of objects that can produce such phenomena.

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