Curtin Team Finds 8-Minute Radio Pulses From White Dwarf Orbiting Sun-like Star

Q: Could our own Sun eventually become part of a rare, radio-pulsing binary system like the newly discovered GPM J071507−114153?

Yes, but only under a very specific and uncertain set of circumstances. The new discovery shows that a Sun-like star can orbit a white dwarf and help produce these rare radio bursts. That matters for the Sun because it confirms that stars like ours can be part of such systems. In about 5 billion years, the Sun itself is expected to become a red giant, shed its outer layers, and end up as a white dwarf. For the Sun to later resemble GPM J071507−114153, it would need a close stellar companion. The key ingredient in the newly found system is not just a white dwarf, but a binary interaction between the white dwarf and a nearby Sun-like star. Researchers found no direct mass transfer there, but they do see strong evidence that the companion’s magnetized corona and plasma environment shape the radio signal through Faraday rotation and likely help power the coherent emission. Our Sun does not have a known stellar companion, so it is not expected to become this kind of radio-pulsing binary on its own. If the Sun remains single, it should become an ordinary white dwarf instead. If, hypothetically, it were in a suitably close binary, stellar evolution could in principle produce a system of the same general type. So the answer is that a Sun-like star can end up in such a system, but the Sun itself is very unlikely to do so because it lacks the necessary companion star and orbital setup.

3 articles · Updated · Curtin University · Nov 12

GPM J071507−114153 emits radio pulses every eight minutes from a white dwarf in orbit with a Sun-like G-type star, the first such system confirmed in this pairing.
More than 100 hours of radio data let researchers track the white dwarf’s orbital motion, showing the pulses come from near the white dwarf or possibly the star itself.
Those signals also exposed magnetic activity on the companion star, including stellar flares and a likely prominence, from more than 5,000 light-years away.
MWA first found the long-period transient, MeerKAT fixed its position, and Keck optical observations tied it to the G-type star.
The Nature Astronomy result expands a class of only about a dozen known long-period transients and points to richer discoveries with future SKA telescopes.