Past Colloquia
Day and Night in the Milky Way: the Dynamics of Planets Orbiting Small Stars
Cody Hall
Sarah Ballard, University of Florida
April 02, 2025
2:00pm - 3:00pm
Abstract: The Solar System furnishes the most familiar planetary architecture: many planets, orbiting nearly coplanar to one another. However, a typical system of planets in the Milky Way orbits a much smaller M dwarf. M dwarf hosts create very different conditions for their planetary systems than…
The History of Galaxy Nuclei
Cody Hall
Anil Seth, University of Utah
March 26, 2025
2:00pm - 3:00pm
Galaxy centers are extremal environments that host massive black holes and uniquely dense nuclear star clusters. My talk will focus on the origin of both of these objects. The formation of massive black holes remains a mystery, but important clues lie in how common they…
From Stellar Streams to Near Field Cosmology: Insights from Large-Scale Spectroscopic Surveys
Cody Hall
Ting Li, University of Toronto
March 19, 2025
2:00pm - 3:00pm
Abstract: Stellar streams serve as exceptional tracers in near-field cosmology, providing critical insights into galaxy formation and evolution, as well as the fundamental nature of dark matter. My talk will feature two major ongoing spectroscopic programs targeting the Milky Way’s streams. The Southern Stellar Stream…
Colloquium with Keith Vanderlinde
Cody Hall
Prof. Keith Vanderlinde
March 12, 2025
2:00pm - 3:00pm
More information coming soon…
Stellar Variability from Minutes to Decades
Cody Hall
Jim Davenport, University of Washington
March 05, 2025
2:00pm - 3:00pm
The past 20 years has seen a revolution in stellar astrophysics driven by high precision data, high cadence data for millions of stars from exoplanet hunting telescopes such as Kepler and TESS. Surveys like ZTF, ASAS-SN, and the upcoming Rubin Observatory push us to explore…
Exploring the Nature of Habitable Sub-Neptunes: From Theory to the Lab
Cody Hall
Xinting Yu, University of Texas San Antonio
February 26, 2025
2:00pm - 3:00pm
Abstract: Sub-Neptunes, planets ranging in size between Earth and Neptune, are the most abundant type of exoplanets discovered to date. However, their nature remains enigmatic, as no such planets exist in our Solar System. Sub-Neptunes are hypothesized to be either bloated terrestrial planets (“super-Earths”), miniature…
Illuminating the Origins of Heavy Elements with Neutron Star Mergers
Cody Hall
Wen-fai Fong, Northwestern University
February 05, 2025
2:00pm - 3:00pm
When we look up at the night sky, we see a static universe. However, observational surveys have revealed that our universe is dynamic, with a myriad of transient events. One of the most captivating contributors to our transient universe are the mergers of neutron stars….
Tidal Sculpting of Short-Period Exoplanets
Cody Hall
Sarah Millholland, MIT
January 22, 2025
2:00pm - 3:00pm
Abstract: A large fraction of exoplanetary systems contain planets that orbit very close to their host stars. With orbital periods in the range of days to weeks, tidal forces become important and lead to significant orbital and physical effects on the planets. In particular, time-varying…
Black Hole Spectroscopy
Cody Hall
Prof. Emanuele Berti
January 15, 2025
2:00pm - 3:00pm
According to general relativity, the remnant of a binary black hole merger is a perturbed Kerr black hole. Perturbed Kerr black holes emit “ringdown” radiation which is well described by a superposition of damped exponentials (“quasinormal modes”), with frequencies and damping times that depend only…
Multi-messenger Hunt for Galactic PeVatrons
Cody Hall
Shuo Zhang, Michigan State University
December 11, 2024
2:00pm - 3:00pm
Abstract: Cosmic rays with energies up to a few PeV are believed to originate from our own galaxy. However, the origin of Galactic cosmic rays has remained a mystery for over a century since their discovery. Recent breakthroughs in neutrino and gamma-ray astronomy have provided…