Astronomy Colloquia
Astronomy and Astrophysics Colloquia - Usually Wednesdays, 3:30 PM, ERC 161, unless otherwise specified. Reception starts at 4:30 PM in Hubble Lounge; persons with a disability who believe they may need assistance, please call the departmental secretary in advance at 773-702-8203 or email See also the list of KICP Wednesday Colloquia which alternate with the Astronomy and Astrophysics Colloquia.

Current & Future Astronomy Colloquia
DateTalk TitleSpeaker
January 25, 2017TBARichard Townsend
February 22, 2017TBAMichael Perryman, GAIA
March 8, 2017TBALynne Hillenbrand, Caltech

Past Astronomy Colloquia
DateTalk TitleSpeaker
January 11, 2017Circumgalactic PrecipitationMark Voit, Michigan State University

Circumgalactic Precipitation
January 11, 2017 | ERC 161 | 3:30 PM
Mark Voit, Michigan State University

Feedback from a central supermassive black hole is an essential component of galaxy evolution models. Without it, those models cannot produce realistic massive galaxies and galaxy clusters. However, the black-hole feedback mechanism remains mysterious. Somehow, accretion of matter onto the central black hole of a massive galaxy becomes precisely tuned so that it regulates radiative cooling and condensation of gas in a volume many orders of magnitude larger than the black-hole's gravitational zone of influence. I will discuss how the required coupling can arise through condensation and precipitation of cold clouds out of a galaxy's circumgalactic medium, and will show how a feedback mechanism that suspends the circumgalactic medium in a marginally unstable state can regulate star formation within galaxies.

January 25, 2017 | ERC 161 | 3:30 PM
Richard Townsend

February 22, 2017 | ERC 161 | 3:30 PM
Michael Perryman, GAIA

March 8, 2017 | ERC 161 | 3:30 PM
Lynne Hillenbrand, Caltech