Colloquia Archives

No Colloquium-Spring Recess
Thursday, March 16, 2023
3:45 p.m.
LGRT 1033
To Be Determined
Thursday, March 9, 2023
3:45 p.m.
LGRT 1033
Title:
To Be Determined:
Nicole Arulanantham, STSci
Thursday, March 2, 2023
3:45 p.m.
LGRT 1033
Title:
UV-driven Evolution and Chemistry of Protoplanetary Disks: Insights from HST’s ULLYSES Program
Abstract:
Beginning in December 2019, approximately 70 T Tauri stars were observed at UV wavelengths through the Hubble UV Legacy Library of Young Stars as Essential Standards Director's Discretionary program (ULLYSES). These publicly available spectra provide critical observational constraints on UV irradiation of protoplanetary disks, a key driver of the gas phase chemistry that sets the initial conditions for planet formation. We use the HST data and radiative transfer models to reproduce the LyA emission seen by surface layers of the gas disks, which typically makes up the largest component of the total integrated UV flux. The model LyA flux available to photodissociate molecules like H2O, HCN, and CH3CN within disks with dust cavities and gaps varies by two orders of magnitude, and we explore how the spread might translate to observable chemical differences. We also investigate whether ultraviolet emission lines from UV-fluorescent H2 can be used to break the degeneracy between disk flaring and UV irradiation of the gas in models of sub-mm CN emission. This work is critical for interpreting molecular features in T Tauri systems observed with ALMA and JWST, demonstrating how UV radiation propagates from the accretion shocks to the outer disks.
Johanna Vos, Postdoctoral Fellow, American Museum of Natural History
Thursday, February 23, 2023
3:45 p.m.
LGRT 1033
Title:
Exometeorology: Weather on Worlds Beyond our Own
Abstract:
Major technological advances have enabled the discovery of a small number of directly imaged exoplanets. These imaged worlds can be studied in far greater detail than exoplanets detected by indirect methods such as transit and radial velocity techniques. Next-generation telescopes such as the recently launched James Webb Space Telescope and the upcoming 30-m telescopes (e.g. ELT, TMT, GMT) will enable direct exoplanet characterization. Based on the handful of exoplanets studied to date, it is clear that interpretation of future observational data hinges on a thorough understanding of their atmospheric processes. In this talk I will discuss our past, current and future efforts to investigate the atmospheres of extrasolar worlds. In particular, I will discuss how a combination of observational and computational techniques will reveal three critical atmospheric processes: clouds, winds and aurorae. Each of these processes are well-studied in our own Solar System and we can now begin to study them on worlds beyond our own. The speaker will be available for one-on-one meetings throughout their 2-day visit: they will be at UMass on Thursday and Amherst College on Friday. If you’re interested in meeting with them, please reserve a slot on the spreadsheet here: https://docs.google.com/document/d/1e0IgfjA4IOtTSroK_KEqm8GMVnyQhq5P7j6fUccu740/edit?usp=sharing.
Thiago Goncalves
Thursday, February 16, 2023
3:45 p.m.
LGRT 1033
Title:
Lyman break analogues: local laboratories for galaxy formation and evolution under extreme conditions
Abstract:
The universe experienced the peak of star formation activity approximately 10 billion years ago, but objects at such epochs are difficult to observe in detail due to the large distances involved. In this talk, I will discuss the background and recent results of a series of works on a sample of local analogues of high-redshift star forming galaxies. These objects, selected based on their high UV luminosities and surface brightness, show characteristics more akin to galaxies at z ~ 1.5-2, while their proximity allows for detailed investigations of a wide variety of physical properties, including (among others) kinematics, gas masses, and environments. They also show signs of nuclear accretion onto central intermediate mass black holes, and as such could act as interesting laboratories for an important brief stage of black hole growth before the M-sigma relation is fully established.
Jason Young
Thursday, December 8, 2022
3:45 p.m.
LGRT 1033
Title:
Halfway to the Peak
Abstract:
This talk presents brand new data from our JWST program "Halfway to the Peak" which investigates the relationship between star forming galaxies and their central black holes at z~0.6, halfway back to the peak epoch of galaxy evolution. This program leverages the rich diagnostic power of mid-IR spectroscopy to separate the AGN and star formation energetics in galaxies, and only now with MIRI/MRS are we able to detect the rich mid-IR atomic lines to quantify the black hole accretion rates ([NeV], [NeVI]) and spatially resolve the star formation (Br-alpha) outside the local Universe. In order to fully realize the potential of these JWST data we developed several novel reduction methods which overcome unforeseen issues with this new instrument. This talk will provide a first look at these data and our future plans for full scientific exploration. Zoom: https://umass-amherst.zoom.us/j/91015254428?pwd=dUlwZ1RadXVMcW1Jd3BiQW1KRFhIdz09
Malena Rice, Yale University
Thursday, December 1, 2022
3:45 p.m.
LGRT 1033
Title:
Insights from the Orbital Architectures of Planetary Systems
Abstract:
The orbital configurations of planetary systems serve as fossilized signatures of their past dynamical evolution. These signatures provide a direct window into planetary systems’ formation histories at both the individual and population level, constraining the prevalence of mechanisms such as migration, secular evolution, and short-term scattering events. My research program investigates the dynamical relationship between stars, planets, and minor planets to demonstrate the key underlying processes that produce the observed diversity of planetary systems. I will draw from interconnected subfields of solar system and exoplanetary science to consider how the interface between subfields can be leveraged to develop a synthesized view of planetary system evolution.
No Colloquium
Thursday, November 24, 2022
3:45 p.m.
LGRT 1033
Title:
No Colloquium
Daniella Bardelez Gagliuffi, Amherst College
Thursday, November 17, 2022
3:45 p.m.
LGRT 1033
Title:
Reconstructing Planet Formation Using Dynamical and Chemical Fossils
Abstract:
The dynamical and chemical signatures of a planetary system are independent fossil records of its past. Orbital parameters are vestiges of its formation and dynamical evolution, while chemical compositions of planets and hosts are fingerprints of the stellar nursery and the protoplanetary disk where they formed. In this talk, I will explain the cutting-edge techniques I am using to measure orbital parameters and compositions and how to leverage them to reconstruct the history of planetary systems at a population scale. Obtaining these measurements in a volume-limited sample will enable robust statistics to develop a probabilistic model of formation mechanisms, observationally constraining their transition from stellar binary to planetary formation for the first time. This analysis will lead to the identification of spectroscopic signatures of formation with next generation observatories as we take our first steps towards a comprehensive theory of star and planet formation to uncover our cosmic origins. The link to sign up to meet with her is here: https://docs.google.com/document/d/1lCpmm1JUVt4zU59AZQ0SeQgzPjaIDxSMWBsLylp6q1A/edit?usp=sharing The Zoom link for the talk is here: https://umass-amherst.zoom.us/j/91015254428?pwd=dUlwZ1RadXVMcW1Jd3BiQW1KRFhIdz09
Hsin-Yu Chen, MIT Kavli Institute, Einstein Postdoctoral Fellow
Thursday, November 10, 2022
3:45 p.m.
LGRT 1033
Title:
Gravitational-wave multi-messenger observations: from the production of gold to the age of the Universe
Abstract:
The detections of gravitational waves from compact binary mergers and the followup observations of electromagnetic emissions together provide a powerful and independent tool to explore the Universe. With successive upgrades to the LIGO and Virgo sensitivities, and hence a growing number of detections, we are prepared to address a number of major questions in astrophysics. In this talk, I will discuss two topics in which I expect critical progress will be made in the next few years: (i) How do we make precise and accurate Hubble constant measurements with gravitational-wave events? (ii) What can we learn about neutron star nuclear physics from gravitational-wave observations? I will close with my outlook on the immense scientific opportunities that the next-generation gravitational-wave detectors will provide. Zoom: https://umass-amherst.zoom.us/j/91015254428?pwd=dUlwZ1RadXVMcW1Jd3BiQW1KRFhIdz09 The speaker will be available for one-on-one meetings throughout their visit. If you’re interested in meeting with them, please reserve a slot on the spreadsheet here: https://docs.google.com/document/d/1tvpckaJweKhE7683e1UK1p09Mg3wE_n1y7DuvNZCwi4/edit?usp=sharing All graduate students and postdocs are welcome and encouraged to join the speaker for an informal lunch discussion from 12:30-1:30 in LGRT 533, which can be attended remotely via https://umass-amherst.zoom.us/j/97165107867.
Daniel Clemens, Professor and Chair, Astronomy Department, Boston University
Thursday, November 3, 2022
3:45 p.m.
LGRT 1033
Title:
Boston University’s Perkins Telescope Observatory: Hands-On (and remote) Science and Education
Abstract:
When Boston University became the sole owner/operator of the 1.8m Perkins Telescope on Anderson Mesa in Northern Arizona in June of 2019, we knew success of the endeavor would depend on the quality of partners we could attract. As negotiations between BU and FCAD have opened, and with the first FCAD observing slated for January, this is a good time to introduce this observatory to the FCAD community. In addition to the equatorial mount telescope and its freshly aluminized mirrors, the Perkins features two multi-function instruments having wide ranges of capabilities. PRISM is the optical wavelength imager, polarimeter, and spectrometer and Mimir is its near-infrared cousin. Science using these instruments over the past nearly two decades remains competitive and unique. In addition, we have featured field trips for students to use the Perkins in our graduate, majors, and introductory non-majors courses. As one of the last, large, hands-on telescopes having no telescope operators, students direct the telescope and data collection themselves, learning more in a few nights than in entire semesters in the classroom. And, using live Skype/Zoom connections back to Boston, entire large non-majors classes have enjoyed staying up all night to remotely participate in, and sometime direct, Perkins data collection for their class projects. Zoom: https://umass-amherst.zoom.us/j/91015254428?pwd=dUlwZ1RadXVMcW1Jd3BiQW1KRFhIdz09
Andrew Battisti, ANU
Thursday, October 27, 2022
3:45 p.m.
LGRT 1033
Title:
Sharpening our view of dust attenuation in galaxies across cosmic time
Abstract:
Dust within galaxies obscures light at UV, optical, and near infrared wavelengths. A description of this dust attenuation and how it evolves with time is a critical ingredient of future precision studies of distant galaxies. To date, there has been little work on establishing the extent to which attenuation curves vary within galaxies. This will be of critical importance to maximize returns from current and imminent facilities capable of high resolution imaging and spectroscopy (e.g., JWST, GMT, ELT). I will discuss my current and future work to address this issue using three state-of-the-art integral field spectroscopic surveys that together span 80% of cosmic time: (1) TYPHOON – a survey of 44 nearby (z~0), large-angular size (>few arcmin) galaxies, (2) MAGPI – a VLT/MUSE large program (340hr) of hundreds of resolved galaxies at z~0.3 across a range of environments (isolation, group, cluster), (3) PASSAGE – a JWST/NIRISS pure-parallel program (591hr) of thousands of galaxies at 1<z<2. By combining these surveys with ancillary data spanning rest-frame ultraviolet to infrared wavelengths, I will obtain a revolutionary view of how galaxies are affected by dust attenuation and how it evolves. As a developer of data products for these surveys, I will also highlight products that will be made publicly available in the future. These data will provide a unique opportunity for legacy science to study spatially-resolved properties of galaxies over cosmic time. Andrew will be available for one-on-one meetings on Thursday. If you’re interested in meeting with them, please reserve a slot on the spreadsheet here: https://docs.google.com/document/d/1Go4ch-RnyhPuOPEW7pctrBxbETtQ_xWbw68-QGb-9V4/edit?usp=sharing
Sanchayeeta Borthakur, ASU
Thursday, October 20, 2022
3:45 p.m.
LGRT 1033
Title:
Exploring Pathways that Feed Galaxies
Abstract:
Abstract: Galaxy growth is a slow but continuous process. The observed properties of galaxies suggest that accretion must continue to support star formation. However, direct observational evidence of gas flows into galaxies have been extremely hard to come by. One of the most promising regions in our search has been the disk-halo interface, where new data are uncovering signs of gas condensation. In this talk, I will discuss the results from our ongoing DIISC (Deciphering the Interplay between the ISM, Stars, and the CGM) survey, which probes the disk-CGM interface with QSO sightlines. I'll discuss our findings in terms of the signpost of gas accretion and galactic feedback and show evidence that structures such as high-velocity clouds and extra-planar gas that are seen in the Milky Way and a few other galaxies are indeed prevalent in most galaxies. These gaseous structures represent a pathway for gas accretion into galaxies and can be one of the primary ways how galaxy disks grow in the nearby Universe.
Dr. Eve Ostriker (Associate Chair of the Department of Astrophysical Sciences and the Lyman Spitzer, Jr., Professor of Theoretical Astrophysics at Princeton University)
Thursday, October 13, 2022
3:45 p.m.
LGRT 1033
Title:
The Two Faces of Star Formation Feedback
Abstract:
In recent years, a major focus of research in galaxy formation and evolution has been on the ability of feedback to limit star formation. This happens at the scale of individual giant molecular clouds (GMCs), which are destroyed largely as the result of the radiation input from massive stars, and at the scale of whole galaxies, in which star formation can be quenched by the ejection of baryons in multiphase galactic superwinds. To understand this “face” of feedback in quantitative detail, high-resolution numerical radiation magnetohydrodynamic (RMHD) simulations with very high spatial resolution and accurate algorithmic implementations for key physical processes are required. I will report on recent results from our group based on simulations of this kind, which (1) allow us to distinguish the relative importance of photo-evaporation and radiation pressure on cloud destruction as a function of GMC properties, and produce observed GMC lifetimes and star formation efficiencies consistent with observations; and (2) provide predictions for the mass, energy, and metal loading scaling relations of galactic winds as a function of the large scale star formation rate. The second “face” of star formation feedback is its role — via radiation and supernovae -- in providing the heating and input of kinetic energy that offsets cooling and dissipation, in order to maintain the observed thermal, turbulent, and magnetic pressure in the three-phase ISM. Our numerical RMHD simulations and associated theory have also advanced understanding of this aspect of feedback, demonstrating that star formation and the ISM reach a co-regulated equilibrium state for a wide range of conditions in disk galaxies. I will argue that it is this equilibrium that underlies observed star formation scaling relations in disk galaxies, and that simple feedback “yield” parameters that encapsulate the complexities of heating/cooling and driving/dissipation processes can be used to predict star formation rates based on the large-scale gas and stellar contents of galaxies, in good agreement with observations. All graduate students and postdocs are welcome and encouraged to join the speaker for an informal lunch discussion from 12:30-1:30 in LGRT 533, which can be attended remotely via https://umass-amherst.zoom.us/j/97165107867. Please let John Weaver know if you are interested in attending dinner with the speaker on Thursday evening, the location of which is TBD.
Dr. Pratika Dayal (Associate Professor and Rosalind Franklin Fellow at The University of Groningen)
Thursday, October 6, 2022
3:45 p.m.
LGRT 1033
Title:
Title: Early galaxy formation and its large-scale effects
Abstract:
Dear all, The next FCAD Colloquium of the 2022-23 series will take place on Thursday, October 6th at 4pm in LGRT 1033. The talk will be held in-person with an online option for all virtual participants. Refreshments will be served at 3:45pm. Zoom: https://umass-amherst.zoom.us/j/91015254428?pwd=dUlwZ1RadXVMcW1Jd3BiQW1KRFhIdz09 Abstract: Galaxy formation in the first billion years mark a time of great upheaval in our cosmic history: the first sources of light in the Universe, these galaxies ended the 'cosmic dark ages' and produced the first photons that could break apart the hydrogen atoms suffusing all of space starting the process of cosmic reionization. At the forefront of astronomical research, the past few years have seen cutting-edge instruments provide tantalising glimpses of such galaxies chaotically assembling in an infant Universe. I will show how this data has provided an unprecedented opportunity to pin down the reionization state of the Universe, understand the physical properties of early galaxies, and study the key physics driving their formation and evolution. Time permitting, I will try to give a flavour of how 21cm emission from the first billion years can provide a powerful testbed for Dark Matter models beyond "Cold Dark Matter". The speaker will be available for one-on-one meetings throughout their visit. If you’re interested in meeting with them, please reserve a slot on the spreadsheet here: https://docs.google.com/document/d/1_8AdWqdkSTRKHUf5hRkwRLbt1RmZV23Gxt2LrlN6Cfw/edit?usp=sharing All graduate students and postdocs are welcome and encouraged to join the speaker for an informal lunch discussion from 12:30-1:30 in LGRT 533, which can be attended remotely via https://umass-amherst.zoom.us/j/97165107867. Finally, please let us know if you might be interested in joining for dinner on Thursday evening, the location of which is TBD. Mauro will be hosting. Cheers, The FCAD Colloquium Organizing Committee Sinclaire Manning, John Weaver, Sean Linden, & Connor Robinson
Rohan Naidu, Harvard CfA
Thursday, September 29, 2022
3:45 p.m.
LGRT 1033
Title:
Studying higH-Redshift Galaxies with JWST
Science Jamboree
Thursday, September 22, 2022
3:45 p.m.
LGRT 1033
Title:
Science Jamboree
Science Jamboree
Thursday, September 15, 2022
3:45 p.m.
LGRT 1033
Title:
Science Jamboree
No Colloquium
Thursday, September 8, 2022
3:45 p.m.
LGRT 1033
Title:
No Colloquium
Emily Martin, University of California Santa Cruz
Thursday, April 28, 2022
3:45 p.m.
LGRT 1033
Title:
TBD
Sinclaire Manning, UMass Amherst
Thursday, April 21, 2022
3:45 p.m.
LGRT 1033
Title:
TBD
Sirio Belli, Harvard/CfA
Thursday, April 14, 2022
3:45 p.m.
LGRT 1033
Title:
TBD
Claire Murray, STScI/JHU
Thursday, April 7, 2022
3:45 p.m.
LGRT 1033
Title:
Finding Galaxy Fuel in Multi-wavelength Surveys of the Diffuse Universe
Abstract:
The diffuse interstellar medium (ISM) dominates the mass reservoirs of galaxies and fuels the formation of star-forming clouds. Measuring its physical properties is vital for understanding galaxies as evolving ecosystems, and also for correcting observations of extragalactic light. In this talk, I will discuss how to leverage multi-wavelength surveys with machine learning algorithms to unveil the structure, properties and kinematics of the diffuse ISM in the Milky Way and nearby galaxies. From deep surveys of Galactic 21 cm absorption, we use machine vision to establish the temperature and density of pervasive HI, with important implications for foreground dust reddening constraints. Outside the Milky Way, we combine new, high-resolution surveys of the Magellanic System from the Australia Square Kilometer Array Pathfinder (ASKAP) telescope, with sensitive UV-IR photometry of embedded stars from Scylla, a 500-orbit Hubble Space Telescope imaging survey, to probe the 3D+ structure of the ISM at low metallicity. These efforts combined will prepare us to maximize the potential of large spectroscopic and photometric surveys in the thrilling, incoming era of the Nancy Grace Roman Space Telescope and the Square Kilometer Array.
Blakesley Burkhart, Rutgers
Thursday, March 31, 2022
3:45 p.m.
LGRT 1033
Title:
Turbulent Beginnings: A Predictive Theory of Star Formation in the Interstellar Medium
Abstract:
Our current view of the interstellar medium (ISM) is as a multiphase environment where magnetohydrodynamic (MHD) turbulence affects many key processes: star formation, cosmic ray acceleration, and the evolution of structure in the diffuse ISM. In part 1 of this talk, I shall review the fundamentals of galactic turbulence and discuss progress in the development of new techniques for comparing observational data with numerical MHD turbulence simulations. In part 2, I will focus on how turbulence affects the long-standing problem of star formation. From scales of giant molecular clouds (GMCs), I will demonstrate how the star formation efficiency can be analytically calculated from our understanding of how turbulence, gravity, and stellar feedback induce density fluctuations in the ISM via a probability distribution function analysis. This analytic calculation predicts star formation rates from pc size scales (GMCs) to kpc size scales in galaxies.
Itziar Aretxaga, INAOE
Thursday, March 24, 2022
3:45 p.m.
LGRT 1033
Title:
Dusty star-forming galaxies in deep extragalactic fields: tracing the stellar build-up
Abstract:
We analyze a representative sample of dusty star-forming galaxies in the Extended Groth Strip (EGS) in the L>~1012Lsun regime. Deep infrared HST imaging from CANDELS allows us to assess the recent claim of morphological transformation with redshift. We find a significant fraction of dusty galaxies to be starbursts, and they otherwise tend to populate the upper region of the Main Sequence of star formation. We support the claim that disks are the dominant morphology, with bulges being developed along the way, in a similar way to other optically-selected massive star-forming galaxies in the field. In preparation for the commissioning of TolTEC, we also show a cosmological motivated dusty star-forming galaxy simulation that allows us to explore the expected global properties of the 1011 Lsun<L<1012 Lsun regime.
No Colloquium: Spring Recess
Thursday, March 17, 2022
Joel Leja, Penn State University
Thursday, March 10, 2022
3:45 p.m.
LGRT 1033
Title:
"Brick by Brick: The Road to a Cohesive & Complete Story of Galaxy Formation"
Abstract:
What is the story of galaxy formation -- when, where, and how did these vast cosmic ecosystems assemble? Armed with new cosmic photometric and spectroscopic surveys, and with James Webb data just around the corner, we are in a better position to answer this question than ever before. Yet these new data also breathe new life into a long-standing challenge in observational galaxy evolution: how do we self-consistently model all of these data? In this talk I present recent progress made using the high-dimensional galaxy SED-fitting code, Prospector. By including flexible, model-agnostic prescriptions for the complex physical processes in galaxy formation (e.g., nonparametric star formation histories), Prospector produces qualitatively new and quantitatively distinct solutions for key galaxy observables such as stellar masses and star formation rates. I demonstrate the impact this has on our large-scale view of galaxy formation with new analyses of the stellar mass function and star-forming sequence, produced via Bayesian population modeling combined with the flexible "normalizing flow" ML technique. I argue that this Bayesian hierarchical modeling approach is the key to coherently disentangle the long-standing challenge of the strong dependence of galaxy SED-modeling on the assumed prior. I demonstrate some first steps in this direction with population models of dust attenuation and the rest-frame optical color--(mass-to-light ratio) relationship. I end by discussing how this "learn from the data" approach will be turbo-charged in the near future by lightning-fast ML-powered inference techniques combined with next-generation data (e.g., the PFS survey, JWST, and spatially resolved analysis).
Elena Murchikova, Institute for Advanced Studies
Thursday, March 3, 2022
3:45 p.m.
LGRT 1033
Title:
Milky Way’s Galactic Center black hole in its natural habitat
Abstract:
The Milky Way’s Galactic Center black hole Sagittarius A* is the closest to us supermassive black hole. It is an ideal candidate to explore near horizon effects, to test alternative theories of gravity, and to learn the mechanics of black hole feeding, accretion, and feedback -- forces shaping galaxies and the Universe as a whole. Despite its proximity, the accretion flow onto it is not well understood. At large scales (10^5 R_sch and beyond), the primary source of information about accretion flow comes from observations of hot X-ray emitting gas. At near horizon scales, the density of the flow is constrained by polarization measurements. At intermediate scales, there are too few model-independent probes to reliably determine physical properties of the gas. In 2019, using ALMA observations I discovered a disk of cool gas at intermediate distances (10^4 R_sch) from the black hole, which provides new clues to the physics of the inner accretion flow of the Sagittarius A*. In this talk, I will review what is known about the structure of the accretion flow around the black hole. I will discuss the properties of the cool disk and what we can learn from it about the structure of the accretion flow. I will show our new realistic simulations of the inner two parsecs of the Galactic Center which, for the first time, captures Sagittarius A*’s multiphase accretion physics.
Laura Cadonati, Georgia Institute of Technology
Thursday, February 24, 2022
3:45 p.m.
LGRT 1033
Title:
Exploring the stellar graveyard with gravitational waves
Abstract:
A new era in astrophysics has begun with the 2015 discovery of gravitational waves from the collision of two black holes in data from the Laser Interferometer Gravitational-wave Observatory (LIGO). The additional 2017 LIGO-Virgo detection of gravitational waves from the collision of two neutron stars in coincidence with a gamma ray burst and a kilonova, elevated multi-messenger astrophysics from concept to tool for discovery and exploration. Many more gravitational wave signals have been observed since then from collisions of compact binary coalescence, and gravitational waves are a new, important probe for understanding the universe, with a rich science potential ranging from astronomy to cosmology to nuclear physics. This talk will present a selection of the latest results from LIGO and Virgo, with their GWTC-3 gravitational wave transient catalog, and an outlook for the next decade.
Grant Tremblay- Harvard/CFA
Thursday, February 17, 2022
3:45 p.m.
LGRT 1033
Title:
The Once & Future Great Observatories
Abstract:
The term “Great Observatory” was once a piece of programmatic branding for four space telescopes launched between 1990 and 2003. No longer. While Hubble, Chandra, Compton, and Spitzer will reign as everlasting triumphs of science, the term “Great Observatory” has transcended these missions alone. It now reflects a vision for transformationally powerful, flexible, and long-lived facilities enabling panchromatic synergy, near-simultaneity, and acting as force multipliers for ground-based facilities around the world. With extended missions that can span decades, Great Observatories become something other than a pursuit of important but narrowly-defined science goals. They become discovery platforms for the questions we have not yet thought to ask. In this talk, I’ll review the past, present, and future of the Great Observatories program, particularly in the wake of Astro2020.

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