Astronomers Classify ASKAP J1745-5051 as 1.3-Hour Accreting White Dwarf Binary
Updated
Updated · Nature.com · Jun 1
Astronomers Classify ASKAP J1745-5051 as 1.3-Hour Accreting White Dwarf Binary
5 articles · Updated · Nature.com · Jun 1
ASKAP J1745-5051 was confirmed as an accreting cataclysmic variable after optical spectra showed magnetic white-dwarf signatures and an orbital period of 1.368 hours.
Radio bursts and X-ray emission repeat on essentially the same cycle—1.34497 hours in radio and 1.32 hours in X-rays—tying the transient directly to the binary’s orbit.
The source shows unusual behavior for long-period radio transients, including highly elliptical polarization, frequency-drifting bursts, narrowband structure and hours-long shutoffs, pointing to emission from magnetized accreting plasma.
Its radio output is about 100 times brighter than known cataclysmic variables, while X-ray flux varies by more than an order of magnitude, strengthening evidence for variable accretion.
The result links at least some long-period radio transients to white-dwarf binaries near the 1.3-hour orbital-period floor and gives astronomers a concrete system for testing how magnetic accretion generates periodic bursts.
Could these 'vampire' white dwarfs be the secret ancestors of even more extreme objects, like neutron stars?
These star systems are 'extreme physics labs.' What fundamental laws of the universe could they help us rewrite or discover next?
Decoding Long-Period Radio Transients: How ASKAP J1745−5051 Reveals the Source of Mysterious Cosmic Signals
Overview
The discovery of ASKAP J1745−5051 marks a major breakthrough in understanding mysterious long-period radio transients. Researchers identified this object as a crucial reference point, providing a clear benchmark for decoding the origins of similar cosmic radio signals. ASKAP J1745−5051 offers a new way to distinguish whether these signals come from accreting white dwarf binaries or neutron stars. As the first unambiguous system with such diagnostic power, it enables scientists to compare future detections and determine their true sources, paving the way for deeper insights into the universe’s most enigmatic radio bursts.