David Setton (Princeton University) - How JWST Broke the Universe (and how we're un-breaking it)

The unprecedented infrared sensitivity of the James Webb Space Telescope promised to reveal the earliest stages of the formation of massive galaxies, long theorized but never directly observed. In the first three years of its operation, it has over-delivered on that promise. Deep JWST observations have revealed an abundant population of massive galaxies at z>3 that appear to have formed earlier than expected in cosmological simulations, raising seriously questions about their progenitor population. At the same time, we identified a mysterious population of "Little Red Dots" at even higher redshift that was interpreted as the dusty, star forming cores of these early-forming massive galaxies. I will demonstrate how we worked to build up the panchromatic spectral energy distributions of Little Red Dots to definitively show that they are not dusty massive galaxies, not dusty active galactic nuclei, and perhaps instead a never-before-seen phase of early supermassive black hole growth. I will then pivot back to massive galaxies, and discuss work from the SQuIGGLE Survey, where we are using panchromatic constraints to resolve the rapid quenching process along all phases of stars, dust, gas, and AGN activity

The Astronomy Colloquium covers a wide range of topics and should be accessible to advanced Astronomy Majors. Refreshments will be served from 3:45pm with the presentation beginning at 4:00 pm.