Cake Talk by Asa Skuladottir
The Milky Way is an environment rich with satellite galaxies, stellar streams and accreted systems. Looking at detailed chemical abundance patterns of individual stars in these systems allows us to trace back different nucleosynthetic sources, such as the first stars, core-collapse supernovae, supernovae type Ia, AGB stars, and neutron star mergers. Recent observations of these systems strongly point to at least two main nucleosynthetic sites of the r-process, supernovae and kilonovae. Furthermore, two recently discovered stars show imprints of very exotic supernovae. One is the most metal-poor star known in any external galaxy and its abundance pattern is consistent with a primordial zero-metallicity hypernovae, with explosion energy E = 10 × 10^51 erg; while the other is a potential descendant of a 260 Msun pair-instability supernovae. The upcoming large spectroscopic surveys will likely provide many more such exciting discoveries, and deepen our understanding of the various nucleosynthetic channels.