Ten Years, Billions of Galaxies, One Sky: The Rubin Observatory Story

A PAS invited talk with Bernardita Ried Guachalla of Stanford University.

Talk Abstract
When the Vera C. Rubin Observatory begins its Legacy Survey of Space and Time (LSST), it will take the most detailed, dynamic map of the southern sky ever made — visiting the entire visible sky every few nights for ten years. This unprecedented dataset will let us track billions of galaxies, discover countless new asteroids, and watch the Universe change in real time. In this talk, I will explore how Rubin’s images will help us tackle some of the biggest questions in cosmology: What is dark matter made of? What is driving the accelerated expansion of the Universe? And how did cosmic structures evolve over billions of years? I will share how my work connects Rubin’s galaxy maps with other surveys, building a multi-wavelength, multi-experiment view of the cosmos.

About Our Speaker
Bernardita Ried Guachalla is a PhD candidate in Physics at Stanford University, specializing in cosmology and large-scale structure. She works with data from major observatories — including the Vera C. Rubin Observatory — to study dark matter, dark energy, and the evolution of the Universe. Originally from Chile, she has received multiple fellowships and awards for her research and outreach, and is part of global collaborations such as DESI, ACT, and the Simons Observatory.