Astronomers Identify First White Dwarf-Main Sequence Star Pairs in Clusters

This discovery offers new insights into binary star evolution and the mysterious common envelope phase.

Researchers at the University of Toronto have discovered 52 candidate white dwarf-main sequence binary systems across 38 open star clusters, a significant increase from only two previously known examples.
These binary systems provide a unique opportunity to study the common envelope phase, a poorly understood stage of stellar evolution where one star engulfs its companion as it expands into a red giant.
The findings help bridge the gap between the early and final stages of binary star systems, shedding light on processes that contribute to phenomena like Type Ia supernovae and gravitational waves.
The team used machine learning to analyze massive datasets from ESA's Gaia mission, 2MASS, and Pan-STARRS1 surveys, enabling the identification of these elusive systems across hundreds of clusters.
This research lays the groundwork for future studies to confirm and characterize these binaries, with implications for understanding stellar life cycles, galaxy evolution, and transient cosmic events.