Abstract:
The most common stars are those smaller and cooler than the Sun, but their complex emergent spectra render challenging detailed studies of their composition and initial formation.  The measurement of isotopic ratios is a key tool that has been used to unlock the formation of our Sun, the Solar System, and the nuclear processes within the comparatively rarer stars that are more massive than the Sun.  I will talk about our measurements — the first to determine multiple isotopic abundances in any dwarf stars beyond the Sun — and our struggle to interpret the data in terms of models of Galactic chemical evolution & enrichment.