The origins of neutron-capture elements (atomic number Z > 30) have historically been discerned from the interpretation of stellar spectra. However, in the last decade nebular spectroscopy has been demonstrated as a powerful new tool to study the origins of n-capture elements, providing unique new information that cannot be attained from stellar spectroscopy alone. In this talk I will discuss exciting new advances in this burgeoning field, including the recent discovery of several previously undetected near-infrared emission lines of heavy elements in planetary nebulae. The newly discovered lines allow for more meaningful comparisons and constraints to models of AGB evolution and s-process nucleosynthesis. These rare elements hold the key to understanding the star formation histories and chemical evolution of galaxies, and it is increasingly important to understand the s-process origins of trans-iron elements in light of the recent evidence for (and difficulty in quantifying!) r-process enhancements in the ejecta of neutron star mergers.
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