Poonam Chandra: Echos of final days of supernovae progenitors and time domain astronomy initiatives at NRAO

Thursday 29 Oct 2026, 13:15 → 14:00 Europe/Stockholm

A5:1003 (AlbaNova Main Building)

A massive star loses material throughout their evolution that forms a complex circumstellar environment, carrying the footprints of the star before its explosive demise as a supernova. When the post explosion supernova blast wave encounters this surrounding material, the resulting interaction generates emission across the electromagnetic spectrum, offering a unique opportunity to probe both the explosion and the progenitor's mass-loss history. In this colloquium, I will present how multi-wavelength observations—from radio and optical to X-ray wavelengths—which are transforming our understanding of circumstellar interaction in supernovae. Recent observations reveal that circumstellar environments are remarkably diverse, reflecting a wide range of progenitor properties and mass-loss mechanisms. I will discuss recent observational results that highlight this diversity and demonstrate how coordinated multi-wavelength studies are reshaping our picture of stellar death. These findings offer important clues to the poorly understood processes governing mass loss in the final years before core collapse. Towards the end I will also summarise the various ongoing time domain astronomy initiatives at NRAO.