Researchers have gained a better understanding of the development of the universe and early stars through the discovery of the oldest star in the Galactic Halo, LAMOST J1010+2358. The study’s findings indicate that the star formed in the gas cloud left behind by a first-generation star with a mass of up to 260 times that of our Sun.
On Wednesday, the journal Nature published a new study led by Chinese astronomers at the National Astronomical Observatories of China (NAOC), funded by the Chinese Academy of Sciences (CAS).
Zhao Gang, the project’s director, stated that the first stars ended the cosmic “dark ages” of the Big Bang by illuminating the cosmos during the cosmic dawn. He further noted that one of the major unanswered questions about the universe is how the mass of these stars is distributed.
Computer simulations of the birth of the first stars suggest that their masses could reach as high as 100 times that of the Sun. Zhao observed, “Among them, the first stars with masses between 140 and 260 solar masses eventually became a special type of supernovae known as pair-instability supernovae [PISN], which would leave a distinct chemical signature in the atmospheres of the next generation of stars.” He emphasized that “no previous direct evidence of such supernovae had been found.”
The star’s chemical composition aligns with the theory of PISN. The Subaru telescope in Japan conducted a follow-up observation after the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) in China helped locate this chemically unusual star.
Xing Qianfan, a significant contributor to the research, stated, “Our discovery provides the first clear direct evidence of a PISN originating from a very massive first-generation star in the early universe.”
Timothy Beers, a professor at the University of Notre Dame in the US, commented, “This paper presents, to my knowledge, the first conclusive connection of a Galactic halo star with an abundance pattern derived from a PISN.”
Wang Xiaofeng, a professor at Tsinghua University, explained, “Next-generation stars carry the elemental imprints.” It is akin to determining a father’s traits by examining the DNA of his child.
Han Zhanwen from CAS emphasized, “Understanding the properties of first-generation stars is crucial for comprehending the formation of stars, galaxies, and the large-scale structure of the universe.”
Toshitaka Kajino, a professor at Beihang University, highlighted, “I believe that this discovery, along with anticipated future findings, may shed light on the still unknown mechanism of very massive black hole formation in the early universe.”