Subaru Telescope | National Astronomical Observatory of Japan | 2014 Aug 21
A team of astronomers from the National Astronomical Observatory of Japan (NAOJ), the Konan University and the University of Hyogo in Japan, the University of Notre Dame, and New Mexico State University has used the 8.2 m Subaru Telescope's High Dispersion Spectrograph (HDS) to discover a low-mass star, SDSS J0018-0939, that exhibits the peculiar chemical abundance ratios associated with the process of creating new atomic nuclei (nucleosynthesis) in a first-generation very-massive star. Until now, no observational evidence has supported numerical simulations of the existence of very-massive stars among the first generation of stars formed after the Big Bang.
The Importance of the Mass of First-Generation Stars
First-generation stars are objects formed in the early Universe (within a few hundred million years after the Big Bang) from gas clouds containing only hydrogen and helium. First-generation stars are the probable precursors of the formation of the Universe's structure and chemical enrichment; large stellar systems, e.g., galaxies, formed later.
Numerical simulations have made significant progress in understanding the formation of the first stars. Recent simulations suggest that a small fraction of very-massive stars with masses exceeding one hundred times that of the Sun could have formed in the early Universe, even though the large majority of first stars formed with masses of ten to a hundred times that of the Sun. Their strong UV radiation and energetic explosions are likely to have had a significant impact on the evolution of stellar systems. ...
A Chemical Signature of First Generation Very Massive Stars - W. Aoki et al
- Science 345(6199) 912 (22 Aug 2014) DOI: 10.1126/science.1252633
- Science 345(6199) 868 (22 Aug 2014) DOI: 10.1126/science.1255524