A group of astrophysicists, suggestively called "stellar archaeologists", recently made a discovery that overturns current knowledge of stellar composition. They identified a star with unusual properties, symbolically named the "Barbenheimer Star", a creative reference to the films "Barbie" and "Oppenheimer", released simultaneously last year. This star, with a chemical composition unlike any other known star, was discovered during a survey of the cosmic history of another equally unusual star.
The discovery came after detailed study of J0931+0038, a distant red giant star originally identified in 1999 by the Sloan Digital Sky Survey (SDSS). However, its peculiarities were not understood until recently, when the SDSS telescopes in New Mexico, along with subsequent observations from the Giant Magellan Telescope in Chile, provided a detailed spectrum of the star. The analysis revealed an unusual metallicity of J0931, characterized by a high concentration of heavy elements.
This unusual metallicity has been analyzed in a new study, uploaded to the arXiv prepublication server, and suggests that J0931 formed from the supernova remnant of an even larger star – 50 to 80 times more massive than our Sun – dating back from 13 billion years ago. This suggests that the metallicity of Stella Barbenheimer, the parent star of J0931, was probably similarly unusual before it exploded.
The explosion of a star defies the laws of physics has left researchers without explanations
Astrophysicist Alex Ji from the University of Chicago, lead author of the study, emphasized the uniqueness of the discovery: “We've never seen anything like this. Whatever happened then, it must have been amazing."
The star J0931 exhibited three unusual aspects of its metallicity. First, it had low levels of lighter elements like magnesium, sodium, and aluminum, which are normally more abundant in stars. Second, it featured a large amount of medium-weight elements such as iron, nickel, and zinc. Finally, the star had an overabundance of heavier elements such as strontium and palladium.
Study co-author Jennifer Johnson, an astronomer at Ohio State University, a PLEASE NOTE that although some stars may individually exhibit these characteristics, their combination in one star is extraordinary.
In general, most stars have the opposite metallicity of J0931, with higher levels of lighter elements and lower levels of heavy elements. This is because stars form from hydrogen and helium, which fuse in their cores to create heavier elements. Thus, J0931's richness in heavy elements, in the absence of an adequate concentration of lighter elements, remains a mystery.
This unusual discovery opens new avenues of research in the field of astrophysics and provides a new level of understanding of the early evolution of the universe.
