Events on Thursday, October 9th, 2025
- WiCOR Seminar
- Wisconsin Center for Origins Research Seminar: Prebiotic Chemical Diversity
- Time: 12:05 pm
- Place: Chemistry Building 1315
- Speaker: Professor Jim Cleaves, Department of Chemistry, Howard University
- Abstract: Professor Jim Cleaves (Department of Chemistry, Howard University) will present a seminar entitled “Prebiotic Chemical Diversity” for the Fall 2025 Wisconsin Center for Origins Research Seminar on Oct 9 at 12:05 PM. This event is intended for a research audience. Learn more at:
- Host: Wisconsin Center for Origins Research
- Astronomy Colloquium
- Old New Worlds: Planetary Destruction and Renewal over Stellar Lifetimes
- Time: 3:30 pm - 4:30 pm
- Place: 4421 Sterling Hall
- Speaker: Dr. Chris O'Connor, Northwestern University
- Abstract: Planetary systems are ubiquitous, but not eternal. In this two-part talk, I will describe recent work on long-term stellar evolutionary and dynamical processes that shape, transform, and destroy planets and planetary systems. In part one, I will introduce the extraordinary exoplanet WD1856b and summarize recent theoretical and observational progress, and enduring challenges, in understanding its formation and evolution. In part two, I will discuss the timely "breaking the chains" problem in exoplanet dynamics, which seeks an explanation for the declining prevalence of mean-motion resonances (MMRs) with age in compact planetary systems. I will describe a possible scenario for breaking the chains through planetesimal interactions and its implications about exoplanet architectures beyond the "ice line."
- Host: Nicholas Stone