U.S. astronomers have observed a binary pair of white dwarfs in which one star is devouring material from its companion [1].
The discovery provides a rare glimpse into the mechanics of mass transfer in ultracompact systems. This observation helps scientists understand how these binary pairs evolve and identifies a key target for future gravitational-wave detectors [1].
A team led by Emma Chickles at the Massachusetts Institute of Technology identified the system, which completes a full orbit roughly every eight and a half minutes [1]. The findings were published in The Astrophysical Journal [1].
In this extreme environment, the two dense stars are locked in a tight orbital dance. The gravitational pull of the primary white dwarf is so intense that it strips material away from the second star, a process that effectively tears the companion apart over time [2].
While other ultra-compact double white-dwarf binaries exist, such as the system ATLAS J1138-5139 which orbits every 28 minutes [2], the 8.5-minute period of this specific pair is significantly more extreme. This rapid orbit allows researchers to study the physics of mass exchange under high-stress conditions [1].
By imaging these interactions, the MIT team can better model the final stages of binary star evolution. The data gathered from this system will serve as a benchmark for instruments designed to detect the ripples in spacetime caused by such dense, fast-moving objects [1].
“One star is actively devouring material from its companion.”
The identification of an 8.5-minute orbital period represents an extreme case of stellar interaction. Because these systems emit gravitational waves as they lose orbital energy, this specific binary provides a high-frequency signal that will be critical for validating the sensitivity and accuracy of next-generation gravitational-wave observatories.
