An international team of astronomers reports the detection of a new extremely metal-poor star using the Gemini High-resolution Optical SpecTrograph (GHOST) at the Gemini South telescope in Chile. The finding was presented in a paper published October 25 on the pre-print server arXiv.
Metal-poor stars are rare objects as only a few thousands of stars with iron abundances [Fe/H] below -2.0 have been discovered to date. Expanding the still short list of metal-poor stars is of high importance for astronomers as such objects have the potential to improve our knowledge of chemical evolution of the universe.
Located some 25,500 light years away from the Earth, SPLUS J142445.34−254247.1, or SPLUS J1424−2542 for short, was detected in 2019 as part of the Southern Photometric Local Universe Survey (S-PLUS). The star has a mass of about 0.84 solar masses, is estimated to be 10 billion years old, and its effective temperature is approximately 4,750 K.
Previous studies of SPLUS J1424−2542 have suggested that its metallicity is at a level of -3.25, therefore it should be classified as an extremely metal-poor star.
Now, a group of astronomers led by Vinicius M. Placco of the University of São Paulo in Brazil, has conducted GHOST observations of SPLUS J1424−2542, which allowed them to perform a chemical study of this star confirming this hypothesis.
2023-11-01 09:00:04
Original from phys.org