| Abstract: Axions and axion-like particles (ALPs) can have weak couplings to the Standard Model which may be magnified in extreme astrophysical environments, opening unique pathways toward observational signatures. In this talk, I will discuss several exciting ways such signatures can manifest. I will begin with an overview of astrophysical light-shining-through-wall setups and novel searches for axion production at the galactic stellar population level. I will then discuss further extensions of these ideas to compact objects, highlighting recent work searching for axions via black hole superradiance and gravitational wave signatures. Finally, I will describe ongoing theoretical and experimental efforts to build GALAXIS, an all-sky MeV gamma-ray satellite mission designed to search for axions from core-collapse supernovae. Throughout, I highlight how these diverse astrophysical environments, together with a new generation of upcoming observations, can open new windows on axion parameter space with real potential for discovery. |