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Colloquium Series

All talks are held on Wednesdays in the STScI John N. Bahcall Auditorium at 3:30 p.m. preceded by tea at 3:15 p.m.

Please direct questions or comments to the colloquium committee. The 2016-17 committee members are Brad Whitmore (chair), Gabe Brammer, Andy Fruchter (ex officio), Olivia Jones and Nora Luetzgendorf.

STScI presents live and archived webcasting of talks and Colloquium Series.

Date Speaker/Title
Feb. 01 (CoolSci Talk Series)
Feb. 08 (No Colloquium)
Feb. 15 Amy Reines (National Optical Astronomy Observatory)
Title: The Origin of Supermassive Black Holes
Abstract: The origin of supermassive black holes remains a major outstanding issue in modern astrophysics. These monster black holes reside in the nuclei of essentially every massive galaxy and power the most luminous quasars at the edge of the observable Universe. However, directly observing the first “seed” black holes in the early Universe - that can eventually grow to upwards of a billion solar masses - is not feasible with current telescopes. Present-day dwarf galaxies, on the other hand, are within observational reach and offer another avenue to learn about black hole seeds since low-mass galaxies can host relatively pristine black holes. In this talk, I will highlight some of my recent achievements in this field that have taken us from a few rare examples to large systematically-assembled samples of dwarf galaxies hosting nuclear black holes. I will also discuss how my work has implications for directly detecting black hole activity in the first galaxies at high redshift.
Host: Nora Luetzgendorf
Feb. 22 Jessica Lu (University of California Berkeley)
Title: Finding Black Holes with Astrometric Microlensing
Abstract: TBS
Host: Andrea Bellini
Mar. 01 Renée Hlozek (University of Toronto)
Title: Constraining Ultra-light Axions with CMB data: Shining Light on the Lightest Particle Dark Matter Candidates
Abstract: TBS
Host: Arfon Smith
Mar. 08 Mike Brown (California Institute of Technology)
Title: Planet Nine from Outer Space
Abstract: TBS
Host: Marc Rafelski
Mar. 15 Raffaella Margutti (Harvard University/Northwestern)
Title: Astronomical Transients that Defy all Classification Schemes
Abstract: Observations are drawing a complex picture of the latest stages of massive stars evolution and their explosions. In this seminar I concentrate on two among the least understood aspects of stellar evolution, adopting an observational perspective: How do massive stars loose a significant fraction of their mass in the years preceding the explosion? What powers the most luminous stellar explosions in our Universe? I address these questions by taking advantage from panchromatic observations of two remarkable transients: (i) the “normal” envelope-stripped SN2014C, which experienced a dramatic metamorphosis and evolved from Type I into Type II supernova over a timescale of a few months, thus violating the supernova classification scheme that hat has existed for decades. (ii) I will then describe the recent results from our efforts to constrain the energy source of Super-Luminous SNe, with a case study of the “bactrian” transient ASASSN-15lh, which might be the first element of an entirely new class of transients.
Host: Andrew Fruchter
Mar. 22 Jo Bovy (University of Toronto)
Title: Galaxy Evolution at High Resolution: the New View of the Milky Way
Abstract: TBS
Host: Gail Zasowski
Mar. 29 Rob Kennicutt (University of Cambridge)
Title: From Gas to Stars
Abstract: It is now clear that the conversion of interstellar gas to stars, together with the subsequent feedback from massive star formation on the ISM are fundamental agents in the formation, evolution, and shaping of galaxies. Thanks to a wealth of recent observations from the ground and space our empiriral characterization of these processes is being revolutionized, yet our understanding of the underlying physical processes which trigger and regulate large-scale star formation remains embryonic. This talk will review the many advances made over the past decade in understanding the coupling of star formation to the interstellar medium, and highlight the key challenges which remain.
Host: Margaret Meixner
Apr. 05 (No Colloquium)
Apr. 12 Armin Rest (STScI)
Title: Taking the Measure of the Universe with Stellar Explosions
Abstract: TBS
Host: Dave Soderblom
Apr. 19 Eliza Kempton (Grinnell College)
Title: Revealing the Atmospheres of Extrasolar Super-Earths
Abstract: TBS
Host: Nikole Lewis
Apr. 26 (Spring Symposium, No Colloquium)
May 03 Jan Cami (Western University)
Title: Space Buckyballs: The Hidden Life of Cosmic Fullerenes
Abstract: In recent years, the fullerene species C$_{60}$ (and to a lesser extent C$_{70}$) has been detected in a variety of astrophysical environments -- from the circumstellar carbon-rich surroundings of evolved stars to interstellar reflection nebulae and young stellar objects. Understanding how these species form, evolve and respond to their environment yields important insights into astrochemistry and the characteristics of large aromatics in space, thought to be the main reservoir of organic material in space. In this talk, I will present an overview of what we have learned about cosmic fullerenes from astronomical observations, theoretical calculations and recent laboratory experiments, and show how fullerenes have significantly changed our under- standing of interstellar chemistry. I will discuss the conditions that appear to be conducive to the formation and/or detection of fullerenes, and highlight some of the difficulties we still face in understanding the formation of fullerenes in planetary nebulae.
Host: Gail Zasowski
May 08 Rainier Weiss (Massachusetts Institute of Technology), Bahcall Lecture
Title: Observation of the Merger of Binary Black Holes: The Beginning of Gravitational Wave Astronomy
Abstract: Rainer Weiss on behalf of the LIGO Scientific Collaboration

After some history of gravitational waves will follow with a description of the waves and the technique for detecting them. Present and discuss the observations and end with a vision for the future of gravitational wave astronomy and astrophysics.
Host: TBD
May 10 Vicky Kalogera (Northwestern University)
Title: Gravitational-Wave Discoveries and Black-hole Astrophysics
Abstract: TBS
Host: TBD
May 17 Adam Leroy (The Ohio State University)
Title: Detailed Physical Conditions and Star Formation in the ISM of Nearby Galaxies
Abstract: TBS
Host: Karl Gordon
May 24 Bob Abraham (University of Toronto)
Title: Exploring the Low Surface Brightness Universe with Dragonfly
Abstract: TBS
Host: David Law
May 31 Jim Fuller (California Institute of Technology)
Title: Asteroseismic Signature of Internal Stellar Magnetic Fields
Abstract: TBS
Host: Steve Lubow