Astronomers have discovered for the first time pairs of binary star systems, consisting of the remnant of a dead star (a white dwarf) and a living star (a main sequence star), within young clusters
Astronomers have discovered for the first time pairs of binary star systems, consisting of the remnant of a dead star (a white dwarf) and a living star (a main sequence star), within young clusters. The study, published on November 15 in the journal "The Astrophysical Journal," sheds light on a critical stage in the evolution of stars and helps solve one of the great mysteries of astrophysics.
Binary star systems are pairs of stars bound together by their gravity. Understanding them allows researchers to learn about the development of stars, the evolution of galaxies, and the processes of creating the elements that make up the universe. Also, these binary systems may be the key to understanding cosmic phenomena such as supernovae and gravitational waves.
Understanding the Common Shell Phase
In the final stages of its life, a star may swell hundreds or even thousands of times its original size, in the processes known as: the 'red giant stage' or the 'asymptotic giant stage'. In close binary systems, this bulge may cause the star to swallow its partner completely. This phenomenon, called the 'common envelope phase', remains one of the great mysteries of astrophysics.
The new study offers a way to study this phase using systems containing a white dwarf and a main sequence star - a remnant of a dead star next to a living star.
According to the lead researcher, Stephanie Grondin, a student at the University of Toronto: "Binary stars play a huge role in our universe. The current sample is a first step in tracking the full life cycles of these systems, and will allow us to study the most mysterious stage of stellar development."
The researchers used machine learning to analyze data from three main sources: the European Space Agency's Gaia spacecraft, the 2MASS survey and the Pan-STARRS1 survey. Using this data combination, the researchers were able to identify 52 binary systems within 38 open clusters.
According to Prof. Joshua Spiegel, from the Department of Statistics and Astronomy at the University of Toronto: "Machine learning has allowed us to automatically identify unique systems, something that would have been nearly impossible to do manually."
Future implications for astrophysics
Binary systems containing stellar remnants are a source of type Ia supernovae and mergers that create gravitational waves - ripples in space-time that can be measured with instruments such as LIGO.
With continued research in telescopes such as Gemini, Keck and Magellan, the team hopes to expand the understanding of these phenomena and influence many areas of astrophysics.
