Scientists locate source of mysterious radio signals after 20 year search: A vampire star and its victim

Key Points:

• Australian radio astronomers have identified that the long-period radio transients, mysterious space signals lasting minutes to over an hour, originate from the interaction between a white dwarf star and its neighboring red dwarf star.
• Using the ASKAP radio telescope, researchers led by Kovi Rose found that in the system ASKAP J1745-5051, a white dwarf accretes matter from a red dwarf, producing both long-period radio bursts and X-ray emissions tied to their 1.4-hour elliptical orbit.
• The radio waves arise from the clashing magnetic fields of the two stars, which strip charged particles that emit synchrotron radiation, while X-rays are generated by hot matter spiraling onto the white dwarf.
• Although this discovery explains the origin of some long-period radio transients, it may not account for all, as only one other such source is known to emit X-rays, suggesting multiple origins for these signals.
• This research provides a framework to better interpret long-period radio transients, potentially distinguishing between those caused by white dwarf systems and those from highly magnetic pulsars like magnetars.