When:
Tuesday, September 23, 2025
11:00 AM - 12:00 PM CT
Where: 1800 Sherman Avenue, 7th floor, 7-600, Evanston, IL 60201 map it
Contact:
CIERA Astrophysics
(847) 491-8646
CIERA@northwestern.edu
Group: CIERA - CIERA Colloquia
Category: Lectures & Meetings
Description:
TBA
Speaker: Lena Murchikova, Northwestern University
Host: Fred Rasio
CIERA Colloquium: Ish Gupta "Ten Years After GW150914: A Population-Level Science with Spectacular Events"
When:
Tuesday, September 30, 2025
11:00 AM - 12:00 PM CT
Where: 1800 Sherman Avenue, 7th floor, 7-600, Evanston, IL 60201 map it
Contact:
CIERA Astrophysics
(847) 491-8646
CIERA@northwestern.edu
Group: CIERA - CIERA Colloquia
Category: Lectures & Meetings
Description:
Ten years after the first direct detection of gravitational waves, gravitational-wave astronomy has moved from a single spectacular discovery to a rich, population-level science. The updated compact binary merger catalog, GWTC-4, now exceeds two hundred mergers of black holes and neutron stars. Using GWTC-4, we can robustly trace astrophysical trends, including features in the black hole mass spectrum and the distribution of spins and tilt angles, which together point to distinct channels of binary formation and evolution across cosmic time. I will begin with these population-level inferences, highlighting the interesting trends that have emerged with the expanded sample. I will then turn to three flagship events from the first part of the fourth observing run (O4a): GW230529, a merger in which the heavier companion lies in the proposed lower mass gap; GW231123, the most massive binary black hole merger observed to date; and GW250114, the loudest signal yet, enabling unusually precise strong gravity tests and clean ringdown spectroscopy. Taken together, O4a shows a field that has matured into one that still delivers headline events while providing statistically grounded, population-level insights into the lives of compact binaries.
Speaker: Ish Gupta, Northwestern University
Host: Vicky Kalogera
CIERA Colloquium: Siegfreid Eggl "Noisy Neighbors: Satellite constellations and ground based astronomy, can they get along?"
When:
Tuesday, October 7, 2025
11:00 AM - 12:00 PM CT
Where: 1800 Sherman Avenue, 7th floor, 7-600, Evanston, IL 60201 map it
Contact:
CIERA Astrophysics
(847) 491-8646
CIERA@northwestern.edu
Group: CIERA - CIERA Colloquia
Category: Lectures & Meetings
Description:
Current estimates see up to half a million artificial satellites being launched in the near future. This rapid industrialization of space promises great opportunity, and could lead to improved connectivity for underserved communities all around the globe. Hundreds of thousands of satellites in Low Earth Orbit also pose unprecedented challenges to ground based astronomy. If not actively avoided, ultra bright satellites can blind detectors of the next generation of radio and optical telescopes such as the Vera C. Rubin Observatory. To address these challenges, the International Astronomical Union has established the Centre for the Protection of the Dark and Quiet Sky (IAU CPS). The IAU CPS promotes cooperation between space industry, astronomers and other stakeholders in order to minimize the impact of satellite constellations on our space environment. In this contribution I will present some of the challenges faced by astronomy as a consequence of the new space race. I will also discuss possible solutions based on real time operational data sharing that could help save the oldest of sciences.
Speaker: Siegfried Eggl, University of Illinois, Urbana-Champaign
Host: Adam Miller
When:
Tuesday, October 14, 2025
11:00 AM - 12:00 PM CT
Where: 1800 Sherman Avenue, 7th floor, 7-600, Evanston, IL 60201 map it
Contact:
CIERA Astrophysics
(847) 491-8646
CIERA@northwestern.edu
Group: CIERA - CIERA Colloquia
Category: Lectures & Meetings
Description:
The dwarf planet Pluto travels an unusual orbital path near the edge of the solar system. Its long term stability is controlled by a mean motion resonance with Neptune and a secular resonance related to the von Zeipel-Lidov-Kozai effect, the latter involving all the giant planets. Understanding the interplay of these resonances has been a topic of deep dynamical analysis ever since Pluto was discovered nearly a century ago. Observational surveys of the outer solar system have now discovered several hundred co-travelers of Pluto. In this presentation I will describe the orbital dynamics of Pluto and co-travelers, share recent insights, and sketch their connections with planet migration in the ancient solar system.
Speaker: Renu Malhotra, Univeristy of Arizona
Host: Yoram Lithwick
CIERA Colloquium: Tiziana Di Matteo "Massive Black Holes: Insights from Cosmological Simulations"
When:
Tuesday, October 21, 2025
11:00 AM - 12:00 PM CT
Where: 1800 Sherman Avenue, 7th floor, 7-600, Evanston, IL 60201 map it
Contact:
CIERA Astrophysics
(847) 491-8646
CIERA@northwestern.edu
Group: CIERA - CIERA Colloquia
Category: Lectures & Meetings
Description:
The enigmatic journey of massive black holes—from their origins as seed populations in the early universe to their growth through accretion and mergers—is a vastly multi-scale phenomenon deeply connected with the process of galaxy formation. Using cutting-edge cosmological simulations, we can unravel aspects of the co-evolution of galaxies and black holes. The simulations provide insights into the elusive population of intermediate mass black holes and also shed light on some of the largest black holes and their mergers. They are invaluable for guiding observational strategies and interpreting current and upcoming data.
Speaker: Tiziana Di Matteo, Carnegie Mellon University
Host: Claude-André Faucher-Giguére