Source of Mysterious Repeating Space Radio Signals Identified

Ekhbary News Agency | 2024-05-15

An international research team, spearheaded by the University of Sydney in Australia, has finally unraveled the mystery behind powerful, repeating radio signals emanating from space, known as "long-period radio transients" (LPTs). This phenomenon, which has long baffled scientists, has been traced to a unique binary star system.

Unveiling the Phenomenon's Nature

Utilizing the Australian Square Kilometer Array Pathfinder (ASKAP) radio telescope, the team successfully pinpointed the true nature of a mysterious object designated "ASKAP J174508.9-505149." Observations confirmed that the source is a white dwarf actively pulling material from a closely orbiting companion star. "For the first time we have pinpointed the origin of these signals," stated Kovi Rose, a doctoral student at the University of Sydney, adding, "We’ve been able to show that the source for one of these transients comes from a white dwarf actively pulling material from a companion star." This discovery indeed fundamentally reshapes our understanding of these enigmatic cosmic signals.

A Unique Binary Star System

Spectroscopic observations revealed that ASKAP J1745-5051 exhibits distinct hydrogen and helium emission lines, optical features characteristic of "magnetic cataclysmic variables." These are close binary systems where a white dwarf, possessing a strong magnetic field, accretes gas from a companion star. Analysis of radial velocities further unveiled an orbital period of approximately 1.368 hours for this binary system, which remarkably matches the radio pulse repetition period of roughly 1.345 hours. This precise correlation directly links the orbital dynamics to the radio emission. The companion star is estimated to be an M6-class red dwarf, orbiting the dense white dwarf at an extremely close distance.