Colloquium by Dan Milisavljevic, Purdue
Supernovae are among the most powerful explosions in the universe. They forge the elements of life, drive the evolution of galaxies, give birth to neutron stars and black holes, and radiate across every messenger: light, neutrinos, and gravitational waves. Yet fundamental questions remain unanswered. Which stars explode, which collapse silently, and what physics tips the balance? The answers are written in the debris that explosions leave behind, if we can learn to read it.
This talk will describe how the James Webb Space Telescope (JWST) has transformed the science of stellar forensics. A comprehensive JWST survey of Cassiopeia A, the youngest known Galactic core-collapse supernova remnant, has uncovered a web-like network of ejecta filaments tracing the turbulent first moments of explosion, alongside circumstellar structures encoding the progenitor star's final, poorly understood stages of mass loss. These data now serve as quantitative benchmarks for three-dimensional explosion simulations. The approach is being extended to other remnants, including the debris of the supernova of 1604, probing the thermonuclear explosions that underpin cosmological measurements of dark energy.
The talk will conclude with JWST's power to directly image the previously unseen progenitor systems of extragalactic supernovae, opening a new window onto which stars explode and why.
Cookies will be available, starting at 3:45.
Host: Tea Temim