Astronomers have discovered a new type of “strange star” covered in ash helium burningwhich they say was likely formed by a rare stellar fusion event.
When searching for so-called “hot stars” with the Large Binoculars Telescope in Arizona, the German team of experts came across two stars with unusual properties.
The two stars, called PG1654+322 and PG1528+025, are inside our galaxy but are somewhere between 10,000 and 25,000 light-years away from Earth.
While the surfaces of ordinary stars are made of hydrogen andheliumThese newly found stars are covered in large amounts of carbon and oxygen – the byproduct of nuclear fusion for helium.
Experts report a “surprisingly high abundance” of both carbon and oxygen in the two stars – each accounting for regarding 20 percent of both stars’ surface composition.
And stars that are covered by this amount of carbon and oxygen, usually have finished nuclear fusion reactions that occur in their core.
However, the temperatures and diameters of the two newly discovered stars indicate that the core of helium It continues to blend inside them – an unprecedented result.
It is believed that this new type of star formed through the fusion of two white dwarfs – hot, dense remnants of long-dead stars.
The research was conducted by a team of astronomers, led by Professor Klaus Werner of the University of Tübühnen, and published in a new paper in the Monthly Notices of the Royal Astronomical Society.
Professor Werner said: “We typically expect stars with the chemical surface composition of the detected stars to have completed a merger. helium At their centers, and being in the final stages of becoming white dwarfs, these new stars are a severe challenge to our understanding of stellar evolution.”
