I will review results on the effects of population III stars on the chemical abundances of the population II stars. Some of the unsolved problems related to this topics will be discussed.
During Big Bang Nucleosynthesis, hydrogen, helium, and small traces of lithium and beryllium were produced. A few million years after BBN, the first stars were formed out of this primordial material. Important questions about star formation, galactic evolution, and the yields of the first supernovae can be answered from the study of these first stars and their descendants. The most chemically...
The Sculptor dwarf spheroidal galaxy is old and metal-poor, making it ideal to study the earliest chemical enrichment in the Local Group. We followed up the most metal-poor star known in this (or any external) galaxy, AS0039, with high-resolution ESO VLT/UVES spectra. Our new analysis confirmed its low metallicity, [Fe/H]=-3.90, and that it is extremely C-poor, with [C/Fe]=-0.33. This adds to...
