Sven Buder

The power and challenges of stellar spectroscopy in the next decade

Stellar spectroscopy provides us with invaluable insights into the chemical composition and evolutionary histories of stars, unlocking the secrets of galaxies on larger scales. Yet, as our datasets grow exponentially, our current focus has shifted towards quantity and coverage, sometimes at the expense of quality. Our models also often struggle to fully capture the complexities of stellar atmospheres and line formation, particularly as stars evolve. This limits our ability to better understand the intricate details of stellar evolution. These challenges are magnified when transitioning from resolved stellar spectroscopy to unresolved systems, where less advanced tools constrain our interpretations of extragalactic observations. In this talk, I will explore the cutting-edge developments in stellar spectroscopy, emphasizing the critical gaps in our models and how they hinder our understanding of stellar and galactic evolution. I will also highlight the potential of ongoing missions like Gaia, GALAH, SDSS-V, and the extragalactic GECKOS project, alongside upcoming facilities such as 4MOST. These instruments promise to revolutionize our ability to probe stellar populations, but achieving the next breakthrough will require a shift toward higher-quality, more precise observations. I’ll conclude by discussing the path forward, bridging the gap between stellar theory and observations, and addressing the biggest unanswered questions in the subfield of stellar spectroscopy.