Fall 2023 IfA Colloquia
Talks home
Date
Speaker
Affiliation
IfA Host
Title (click for abstract)
Aug 23
Zoom
Peter Gao
Carnegie Institution for Science
Liu
Aug 23
IfA Hilo; 2:30pm
Matthew Richter
UC Davis
Rayner
Aug 30
Douglas Finkbeiner
Harvard University
Tonry
Sep 6
Zoom
Philip Muirhead
Boston University
Huber
Sep 13
David Jones & Zach Hartman
Gemini Observatory
Kleyna
Oct 4
Zoom
Marc Kuchner
NASA GSFC
Liu
CANCELLED
Oct 4
IfA Hilo; 2:30pm
B-G Andersson
Universities Space Research Association
Rayner
Talks are held at 11:45am HST Wednesdays in the IfA Mānoa Auditorium (C-214) unless otherwise noted.
For additional information, please contact Dr. Fabio Bresolin.
Missed a talk? See if there’s a recording at the IfA YouTube channel!
The IfA colloquia are kindly sponsored by the Friends of the IfA.
A Cosmic Infrared Passage
Thomas Jarrett
Professor
University of Cape Town / iYunivesithi yaseKapa / Universiteit van Kaapstad
In this talk I will showcase several of the most powerful scientific applications made possible by the infrared as I highlight the research that I have done over the years, starting as a postdoc developing the Palomar Prime Focus Infrared Camera, through my years as a NASA mission scientist working on IRAS, 2MASS, ISO, Spitzer, Herschel, and WISE, with sideways adventures with the WIRO, Kuiper, IRTF, HST-NICMOS, Palomar-WIRC, and most recently with JWST. I will then focus on my primary research in the field of galaxy evolution in the Cosmic Web, using WISE, optical redshifts, and radio HI surveys. I will finish with my perspective on the IRTF’s role in the coming age of the great NEO and transient surveys.
Unveiling the early stages of planet formation
Myriam Benisty
Staff Astronomer
Institute of Planetology and Astrophysics of Grenoble & Lagrange, Nice, France
Website
Recent observing campaigns have revealed a great diversity in exoplanetary systems whose origin is yet to be understood. How and when planets form, and how they evolve and interact with their birth environment, the protoplanetary disks, are major open questions. Protoplanetary disks evolve and dissipate rapidly while planets are forming, implying a direct feedback between the processes of planet formation and disk evolution. These mechanisms leave clear imprints on the disk structure that can be directly observed. In the past few years, high-resolution observations of protoplanetary disks obtained in the infrared scattered light and in the millimeter regime have led to exquisite images and shown that small scale structures are ubiquitous in protoplanetary disks, and could result from the dynamical interaction with embedded planets. I will present recent observational results on protoplanetary disks that allow us to probe the disk structure and the dynamics of solids, and in particular, in the so far unique system that hosts two directly imaged protoplanets, PDS70. I will conclude on the exciting perspectives in the field of planet formation, driven by the development of new instrumentation.
Dawn of the JWST Era: A New Chapter in Exoplanet Characterization
Peter Gao
Staff Scientist
Carnegie Institution for Science
Website
With the successful launch and commencement of science operations of JWST, the characterization of exoplanet atmospheres has entered a new era. In this talk, I will first give an overview of the exciting programs that have and will be executed by JWST in cycle 1, and then go in-depth into a few of those programs, including discussing the key science results from the Transiting Exoplanet Early Release Science Program and the General Observer program targeting the mysterious sub-Neptune, GJ 1214b. These programs showcase the power of JWST’s high precision and extended wavelength range in revealing atmospheric composition, thermal structure, and the presence and characteristics of clouds and hazes.
The IRTF over the next 10 years: Continuing to serve the community and exceeding expectations
Matthew Richter
Research Physicist
University of California, Davis
For a 3m telescope, the IRTF has consistently been able to “punch above its weight”. Much of this ability is due to clever instrumentation strategies, responsive operations, and a deeply embedded “can-do” attitude. We are now in the JWST/ALMA era with ELTs visible on the horizon. By building on its strengths and capabilities, I believe the IRTF will continue to be productive into the future. Of personal importance to me is ensuring that TEXES, the visitor instrument from UT Austin that first observed at the IRTF in October 2000, is readily available to the IRTF community in the future. The high spectral resolution of TEXES makes it unique and consequential even in the JWST era. Among the lessons from my experience with TEXES (and EXES on SOFIA) are the value of near realtime data reduction pipelines and the potential benefit from atmospheric modeling in data reduction. These software capabilities should be a priority for every IRTF instrument going forward. With the continued spirit of the IRTF community, I have no doubt that the observatory will be productive in the future.
Mapping dust in 3D: A billion parameter inference problem
Douglas Finkbeiner
Professor of Astronomy and of Physics
Harvard University
Website
3D Dust Mapping
Physical processes in the interstellar medium happen in 3 spatial dimensions, but most of our ISM maps are either 2D, or 3D where the third dimension is velocity. A true 3D map is hard to come by! My group has pursued two different approaches to inferring the ISM dust density in 3D by using the brightnesses and colors of billions of stars. One is optimized for angular resolution and larger distances (Bayestar) and one is optimized for high distance resolution, but only within 1.25 kpc. I will describe how we construct these maps and the data sets they are based on.
The Race to the Bottom: The Search for Planets around Ever Smaller Hosts
Philip Muirhead
Associate Professor
Boston University
Director
Perkins Telescope Observatory
Website
Data from NASA’s Kepler and TESS Missions show that low-mass stars, specifically M dwarf stars, are swarming with terrestrial exoplanets. The results have inspired several surveys for exoplanets orbiting stars at the bottom of the main sequence and have led to a renewed interest in the fundamental properties of low-mass stars. I will present recent results from the Low-mass Star Group at Boston University in these areas. We are particularly interested in measuring M dwarf elemental abundances; however, this is confounded by the role of the stellar carbon-to-oxygen ratio and Zeeman enhancement of individual absorption lines. I also will present recent results on the M dwarf mass-radius relationship. Lastly, I will discuss a new search for transiting planets and satellites around L and T dwarfs called the Perkins Infrared Exosatellite Survey, or PINES. L and T dwarfs can be either stars, brown dwarfs or planetary-mass objects, all of which have proto-planetary disks early in their lives. Their disks, combined with the increase in exoplanet occurrence with decreasing host mass seen in M dwarfs, suggest that L and T dwarfs may also be swarming with planets and moons, which motivates the PINES project. I will describe the survey and present our latest results.
Introduction to Gemini Observatory in the 2020s: How to Propose for Time, Complete your Program, and Reduce your Data
David Jones
Assistant Astronomer
Gemini Observatory
-and-
Zach Hartman
Gemini Science Fellow
Gemini Observatory
For the past two decades, Gemini Observatory’s twin telescopes have provided the astronomical community with telescope access to the entire sky. With a full range of observing capabilities from the optical to NIR, Gemini allows scientists from around the world to conduct ground-breaking science from the Galactic center to exoplanets to cosmology, and its capabilities and support infrastructure will be improving significantly over the coming years. In this talk, we present an update on Gemini’s capabilities, proposal process, observing queue system, data reduction software, and user support system. Our goal is to help the UH community 1) take advantage of Gemini for their science needs and 2) provide resources for working with Gemini staff to make the best use of Gemini capabilities and data.
The Revitalization of Gemini Observatory
Jennifer Lotz
Director
Gemini Observatory
For two decades, the International Gemini Observatory has powered astronomical discovery for the entire U.S. community and the international Gemini partnership. Gemini’s twin 8.1m optical/infrared telescopes provide nightly access to both hemispheres of the sky, and host a wide suite of imaging, spectroscopic, and adaptive optics capabilities. Gemini Observatory is one of the world’s most flexible and agile 8m class observatories, enabled by remote nightly queue operations, instrument swapping on timescale of minutes, and responsive scheduling of observations.
In the next decade, Gemini seeks to provide transformational capabilities to fuel discovery in the fields of planetary systems, compact objects, cosmology, and galaxy assembly. Gemini is undergoing a major revitalization of its instrumentation suite, AO facilities, and user support infrastructure. With the advent of Rubin Observatory and LSST, Gemini is well-poised to lead the follow-up of the time-varying sky, and is developing the capabilities to ensure success in the time domain while preserving access for static universe studies.

Gemini North at sunset featuring the new photovoltaic panels and the shadow of Maunakea rising, as the telescope starts to open up for evening observations. Credit: International Gemini Observatory/NSF’s NOIRLab/AURA/J. Pollard
Hoʻoleilana: An Individual Baryon Acoustic Oscillation?
Brent Tully
Astronomer Emeritus
University of Hawaiʻi Institute for Astronomy
Theory of the physics of the early hot universe leads to a prediction of baryon acoustic oscillations (BAOs) that has received confirmation from the pairwise separations of galaxies in samples of hundreds of thousands of objects. Evidence is presented here for the discovery of a remarkably strong individual contribution to the BAO signal at z = 0.068, an entity that is given the name Hoʻoleilana. The radius of the 3D structure is 155/h75 Mpc. At its core is the Boötes supercluster. The Sloan Great Wall, Center for Astrophysics Great Wall, and Hercules complex all lie within the BAO shell. The interpretation of Hoʻoleilana as a BAO structure with our preferred analysis implies a value of the Hubble constant of 76.9 km/s/Mpc.
TBA
Marc Kuchner
Research Astrophysicist & Citizen Science Officer
NASA Goddard Space Flight Center
Website
Coming soon.
Let’s go get the data!
B-G Andersson
Principal Scientist
SOFIA Science Center, Universities Space Research Association
The Infrared Telescope Facility faces both great opportunities and challenges. The launch of the JWST is a momentous event for mid-infrared astronomy. It provides amazing capabilities as well as a large and well-funded user community. While IRTF cannot compete head-to-head with JWST, there are numerous unique and complementary observational methods and capabilities of the IRTF, that provide important synergies. IRTF can also leverage the well-funded JWST user community to enhance its own research, and support.
Some of the unique capabilities of the IRTF are high-resolution spectroscopy, as well as IFUs, and MIR polarimetry capabilities. It provides more nimble time-domain capabilities for transient events and larger sky availability for monitoring observations, with a [much] smaller Sun avoidance angle than space-based observatories, crucial for e.g. Venus and comet observations. IRTF can take advantage of on-going instrument and detector development, to enhance existing instruments and provide new capabilities. Continuing its nimble operations, targeting unique (and new) instruments and deep community contacts (instrument developers and users), the IRTF will remain a vital player in 21st century IR astronomy.
TBA
Thales Gutcke
NASA Hubble Fellow
University of Hawaiʻi Institute for Astronomy
Website
Coming soon.
TBA
Thayne Currie
Associate Professor
University of Texas at San Antonio
UTSA page
Astrophysicist
NAOJ/Subaru Telescope
Subaru website
Coming soon.
TBA
Devin Chu
Keck All-sky Precision Adaptive Optics (KAPA) Postdoctoral Scholar
UCLA
Website
Coming soon.
TBA
Yaguang Li
Beatrice Watson Parrent Fellow
University of Hawaiʻi Institute for Astronomy
Website
Coming soon.
TBA
Theron Carmichael
NSF MPS-Ascend Postdoctoral Fellow
University of Hawaiʻi Institute for Astronomy
Website
Coming soon.
TBA
Justin Pierel
NASA Einstein Fellow
Space Telescope Science Institute
Coming soon.
TBA
Jeff Cooke
Professor
Swinburne University of Technology
Coming soon.