Astronomers discover a binary star system that will go supernova

An international team of astronomers led by researchers from the University of Warwick has made a very interesting discovery. The team has discovered a binary star system that's heading towards supernova, which is very rare. The telltale sign of the binary system heading towards its demise is a teardrop-shaped star.The shape is caused by massive and nearby white dwarf distorting the star with its intense gravity. That intense gravity is the catalyst for an eventual supernova that will consume both stars. The binary duo is one of only a small number of star systems discovered that will one day see a white dwarf star reignite its core.

Researchers published a study revealing that the binary pair is in the early stages of a spiral that is expected to end in a Type Ia supernova, a type of supernova that can help astronomers determine how fast the universe is expanding. Astronomers dubbed the pair HD265435, and they are located about 1500 light-years away. It consists of a hot subdwarf star and a white dwarf star that orbit each other closely with an orbital rate of 100 minutes.

A white dwarf star is a star that exhausted all of its fuel and collapsed in on itself, making it very small but extremely dense. A Type Ia supernova is believed to occur when a white dwarf re-ignites its core leading to a thermal nuclear explosion. Astronomers say there are two situations where this happens. The first sees the white dwarf gain enough mass to reach 1.4 times the mass of our Sun, known as the Chandrasekhar limit.

HD265435 is expected to fit in with the second scenario, where the total mass of a stellar system of multiple stars is near or above that limit. Researchers have only discovered a small number of star systems that will reach the Chandrasekhar limit and result in a Type Ia supernova. Astronomers observed the hot subdwarf star using data from the NASA Transiting Exoplanet Survey Satellite but could not see the white dwarf because its companion is much brighter. The white dwarf is expected to go supernova in about 70 million years.