School of Physics and Astronomy, Cardiff University, Queens Buildings, 5, The Parade, Cardiff
CF24 3AA, UK
Reports of high metallicities in galactic systems have always been controversial. I disuss whether observational claims both for nebulae and for stars are well-founded, and try to form a rational view of just how metal-rich some regions of galaxies do become. Metallicity is linked to the evolution of star formation in a galaxy through the yield, the mass of metals produced each time star formation locks up unit mass of interstellar material. The mechanisms by which real or apparent high yields might be achieved are examined - global and local gas flows, poor mixing, star formation and metallicity effects in stellar evolution. As perhaps expected, it turns out to be not so easy to 'get rich', quickly or otherwise -suggesting that sorting out the lingering uncertainties in the abundance analysis of H11 regions and stars remains a priority.
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