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An extremely primitive star in the Galactic halo |
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| Authors: | Caffau Elisabetta Bonifacio Piercarlo François Patrick Sbordone Luca Monaco Lorenzo Spite Monique Spite François Ludwig Hans-G Cayrel Roger Zaggia Simone Hammer François Randich Sofia Molaro Paolo Hill Vanessa |
| Affiliation: | Zentrum für Astronomie der Universit?t Heidelberg, Landessternwarte, K?nigstuhl 12, 69117 Heidelberg, Germany. Elisabetta.Caffau@obspm.fr |
| Abstract: | The early Universe had a chemical composition consisting of hydrogen, helium and traces of lithium; almost all other elements were subsequently created in stars and supernovae. The mass fraction of elements more massive than helium, Z, is known as 'metallicity'. A number of very metal-poor stars has been found, some of which have a low iron abundance but are rich in carbon, nitrogen and oxygen. For theoretical reasons and because of an observed absence of stars with Z? |
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