Radio pulses link white dwarf to sun-like star in rare system

Pulses originate from dead star

Researchers at the Curtin University node of the International Center for Radio Astronomy Research identified a unique stellar pairing. The system contains a white dwarf that spins every eight minutes alongside a G-type star similar to our sun. For the first time, scientists have detected radio pulses emanating from a white dwarf that orbits a sun-like companion. In the past, these signals appeared exclusively within systems containing smaller and cooler red dwarf stars.

Team processed vast data sets

At the Pawsey Supercomputing Research Center, the research team analyzed over 100 hours of radio data. They used the Murchison Widefield Array to scan the Milky Way visible from Australia for these rare objects. Subsequent observations with the MeerKAT radio telescope in South Africa determined the precise position of the new system. Optical observations from the W.M. Keck Observatory on Maunakea confirmed the association with a G-type star.

Signals reveal distant stellar storms

Associate Professor Natasha Hurley-Walker noted that the pulses allowed detection of stellar flares on the sun-like star. These flares are similar to those that create aurorae here on Earth over 5,000 light-years away. The team also saw the white dwarf moving behind a strong magnetic field region likely caused by a stellar prominence. Since the initial discovery in 2021 by the ICRAR team, approximately a dozen long-period transients have been identified.