Past Colloquia
The All-Sky Automated Survey for Supernovae (ASAS-SN)
Cody Hall, AB 107
Christopher Kochanek (Ohio State University)
October 04, 2017
14:00 - 15:00
The goal of ASAS-SN is to monitor the entire visible sky on a nightly basis for bright transients. ASAS-SN will reach this goal by the end of 2017. In the interim, ASAS-SN already dominates the discovery of bright supernovae (
Life Beyond Earth: Are Any Habitable Worlds Actually Inhabited?
MP 137, 60 St. George Street
Jill Tarter (SETI Institute)
September 28, 2017
15:00 - 16:00
Are we alone? Humans have been asking this question throughout history. We want to know where we came from, how we fit into the cosmos, and where we are going. We want to know whether there is life beyond the Earth and whether any of…
Galactic Archeology: The story of our Milky Way
Cody Hall
Keith Hawkins (Columbia University)
September 20, 2017
14:00 - 15:00
One of the key objectives of modern astrophysics is to understand the formation and evolution galaxies. In this regard, the Milky Way is a fantastic testing ground for our theories of galaxy formation. However, dissecting the assembly history of the Galaxy, requires a detailed mapping…
The James Webb Space Telescope and the landscape of observational astronomy in the 2020s
Cody Hall
Sarah Kendrew (European Space Agency)
February 10, 2017
14:00 - 15:00
Abstract: Building on the groundbreaking successes of the Hubble Space Telescope, the James Webb Space Telescope will open new windows on the Universe at infrared wavelengths. I will present the latest status of the mission, the roadmap towards science operations, and some of the scientific…
The distribution of stellar mass in galaxy clusters over cosmic time
Cody Hall
Remco van der Burg (CEA Saclay)
January 20, 2017
14:00 - 15:00
Galaxy clusters are the most massive gravitationally collapsed structures in the universe, and they have important cosmological and astrophysical applications. Measurements of the radial distribution of galaxies in clusters show how galaxies trace the underlying dark matter distribution, and provide constraints on the physics related…
Towards observational constraints on mapping between cosmological redshift and cosmic scale factor
Cody Hall
Radek Wojtak (Stanford University)
January 13, 2017
14:00 - 15:00
The standard relation between the cosmological redshift and cosmic scale factor is arguably one of a few unverified theoretical inputs underlying the computation of cosmological observables and modern cosmological inference. However, the richness of cosmological observations allows to change its theoretical status and the relation…
Low Mass Galaxies and their Gas at the Peak Epoch of Star Formation
Cody Hall
Dawn Erb (University of Wisconsin–Milwaukee)
December 09, 2016
14:00 - 15:00
Because faint, low mass galaxies are numerous at high redshifts, their impact on the Universe is expected to be significant. They may host a substantial fraction of the Universe’s star formation, provide many of the energetic photons needed to reionize the intergalactic medium, and affect…
Filaments: Fad or Fundamental?
Cody Hall
Alyssa Goodman (Harvard University)
December 02, 2016
14:00 - 15:00
As the resolution of imaging of the dense interstellar medium has improved, we have gone from a very blobby view, featuring interstellar “clouds,” to a much more “stringy” view, featuring interstellar “filaments.” Some three-dimensional shapes in the ISM have a very limited set of possible…
Puzzles in Galaxy Scaling Relations
Cody Hall
Stephane Courteau (Queen’s University)
November 25, 2016
14:00 - 15:00
Galaxies like our Milky Way can be described in terms of their structure, dynamics, and stellar populations. Some very robust correlations between galaxy structural properties, such as total luminosity, maximum circular velocity, and size display rather small scatter, hinting at well-regulated galaxy formation processes. A…
The Thermal Odyssey of the ionized Intergalactic Medium
Cody Hall
Matt McQuinn (University of Washington)
November 18, 2016
14:00 - 15:00
I will summarize the history of IGM temperature measurements from the Lyman-alpha forest as well as the theory for the IGM temperature after reionization. I will show that the simplest theory for thermal evolution, which has little parametric freedom, works remarkably well at reproducing recent…