Biography: Professor Begelman is a Distinguished Professor in the Department of Astrophysical and Planetary Sciences. He has made highly influential contributions to high-energy theoretical astrophysics. His ground-breaking papers on the origins of extragalactic radio sources, “quasi-stars,” and the astrophysics of black holes have made seminal contributions to our understanding of and evidence for black holes

Biography: Earl Bellinger is an Assistant Professor in the Department of Astronomy, with a secondary appointment in the Foundations of Data Science Institute. Earl leads the Yale AstroML (YAML) research group, which focuses on using big data and artificial intelligence to make progress in problems throughout astronomy & astrophysics. The group is particularly interested in

First Observations from the PFS Galactic Archaeology Survey The Subaru Prime Focus Spectrograph is a new wide-field, massively multiplexed spectrograph at the prime focus of the Subaru 8 m telescope.  In March 2025, it began a 360-night survey spread over six years.  About one third of the survey is dedicated to Galactic Archaeology: (1) dark matter

Biography: Prof. Peter works at the interface of particle physics and astronomy to answer the question: What is dark matter? Dark matter is five times more abundant in the universe than normal matter, yet its nature is unknown. Its existence is a window into new physics. As a theorist, Prof. Peter uses models for the

Biography: Margutti’s research is positioned in the new field of Multi-Messenger Astrophysics with Gravitational Waves. Margutti and her research team utilize observations of the most violent Transient Astrophysical Phenomena in the Universe, including stellar eruptions, stellar explosions, mergers of neutron stars and black holes, as well as stellar tidal disruptions by supermassive black holes. Margutti

Biography: Daryl is a Professor of Physics at McGill University in the Trottier Space Institute at McGill and holds a Canada Research Chair in Multi-messenger Astrophysics. Daryl studies the Galactic center and Sgr A*, electromagnetic counterparts to gravitational wave sources, accreting compact objects, and supermassive black holes and their host galaxies, using multi-wavelength and time

Three Preludes on a Theme of Magnetars: Spindown, Nucleosynthesis, and Giant Flares Todd Thompson, Professor and Department Chair Neutron stars born with magnetic fields greater than 1014 G (“magnetars”) are common in the Galaxy. Approximately 10 – 50% of the young neutron star population possesses such field strengths. These objects exhibit very slow rotation, spectacular

Biography: Eduardo is a staff astronomer and group leader at the Max Planck Institute for Astronomy in Heidelberg, Germany. His group focuses on the first billion years of the Universe (redshifts z > 5.5), when the earliest sources of light reionized the intergalactic medium. They discover and characterize the highest-redshift quasars and their cosmic environments

Biography:Daniel is the NuSTAR Project Scientist at NASA JPL. His research interests lie in observational cosmology, including identifying and studying high-redshift galaxies and galaxy clusters, as well as active galaxies. He is particularly interested in understanding the cosmic history of black hole formation and activity. (Adapted from NASA JPL)

Biography: Prof. Ehud Nakar works on a range of topics in theoretical and numerical high energy astrophysics and in particular the physical processes that are active in sources of high energy radiation, cosmic-rays, neutrinos and gravitational waves. Among the astrophysical phenomena that are being explored are neutron-star mergers, gamma-ray bursts, supernovae and soft gamma-repeaters. Physical

Biography: Professor Amon and her group are focussed on the ground-breaking Rubin Observatory’s Legacy Survey of Space and Time, which will image more than 1 billion galaxies. They use galaxies to map the large-scale structure and confront questions about the composition and evolution of our Universe. Ultimately, their goal is to understand the nature of

NICER and the properties of dense matter in neutron stars Precise and reliable measurements of neutron star radii and other properties are essential to our understanding of cold, catalyzed matter beyond nuclear saturation density. Over the last fifteen years, measurements of high-mass neutron stars, gravitational waves from the double neutron star merger GW170817, and X-ray

Dynamics and Transients Form Galactic Centers The centers of most galaxies harbor supermassive black holes orbited by millions of stars and, likely, thousands of stellar-mass black holes. Gravitational scattering drives mass segregation: the heavier stars and black holes sink toward the center and dominate the dynamics of the innermost region. Consequently, massive stars should be

The “dim” future of exoplanet imaging A key goal in astronomy is obtaining direct images and spectra of Earth-like planets to assess their habitability. These “exo-Earths” are so faint–both in absolute terms and relative to their host stars–that they pose extreme technical challenges, ranging from picometer-level optical accuracy to photon-counting detectors. Efforts to overcome these

New Frontiers in Transient Astrophysics: Multi-Messenger Insights into Neutron-Star Mergers and Heavy-Element Formation The detection of GW170817 was a watershed moment in astrophysics, providing the first direct glimpse of a neutron-star merger through both gravitational waves and electromagnetic radiation. This event confirmed that such mergers forge much of the Universe’s heaviest elements, including gold and

The Search for Other Earths The discovery of a true Earth twin (an Earth-mass planet orbiting a Sun-like star within the habitable zone) has been a long-standing goal in the field of exoplanets, and advances in observational technology over the past decades have been moving us ever closer to achieving it. Modern extreme precision radial

Collapsar Disk Outflows: Nucleosynthesis and Multimessenger Signatures Core collapse of a rapidly rotating massive star can lead to a “failed” supernova, forming a black hole surrounded by a neutrino-cooled accretion disk. These collapsar systems are natural laboratories for high-energy astrophysics, capable of powering long-duration gamma-ray burst jets and driving slower, energetic outflows that can unbind

The Massive, Multiphase Circumgalactic Medium in High Definition The environments extending hundreds of kiloparsecs from bright galaxies are now well-known to contain massive amounts of metal-enriched gas that spans several orders of magnitude in temperature (from ~10^4-10^7 K). Galaxy formation theory suggests that this material — the circumgalactic medium (CGM) — is destined to become

Testing Galaxy Formation Models with Large-scale Surveys of the Milky Way Stellar Halo While the vast majority of the light from our galaxy comes from the Galactic disk, the vast majority of the mass of the Milky Way (MW) is in its dark matter halo. Because we cannot directly observe the MW’s dark matter halo,

FRB science results from CHIME Fast radio bursts (FRBs) are a recently discovered, poorly understood class of transient event, and understanding their origin has become a central problem in astrophysics. I will present FRB science results from CHIME, a new interferometric telescope at radio frequencies 400-800 MHz. Since 2018, CHIME has found ~20 times more

Astronomy at a Turning Point: How a constellation of large space telescopes can revolutionize space sciences and enable statistical surveys of exoplanet biosignatures In this talk, I will argue that astronomy is at a major turning point: Our current paradigm for building space observatories cannot meet our science requirements but – through innovation and new

A Local View of Stellar Astrophysics in the Early Universe Energetic feedback from low-metallicity massive stars regulates the evolution of low-mass galaxies, both nearby and in the early Universe. To understand those processes requires robust models of massive star formation, evolution, and ionizing photon production at low metallicity. Yet, these models remain largely theoretical and

This event is CANCELLED due to severe weather. Updated 2/23/2026 First Observations from the PFS Galactic Archaeology Survey The Subaru Prime Focus Spectrograph is a new wide-field, massively multiplexed spectrograph at the prime focus of the Subaru 8 m telescope.  In March 2025, it began a 360-night survey spread over six years.  About one third

The Growth of Supermassive Black Holes Our Accretion History of AGN (AHA) project uses a wedding-cake combination of X-ray+infrared+optical surveys to assess supermassive black hole accretion over cosmic time. X-ray selection means the AGN samples are largely unbiased against obscuration, so our population synthesis model (Ananna et al. 2019)—the only model that fits all available

Characterizing the Chemical Landscape of Planet Formation Planetary systems are made from the dust, gas, and ice in the rotating disks around young stars. Consequently, the answers to some of the most pertinent questions in exoplanet science hinge on our knowledge of protoplanetary disk chemistry. High-sensitivity observations with the Atacama Large Millimeter Array allow us

The SPHEREx Mission: an All-Sky Spectral Survey Like No Other Since its flawless launch in March 2025, NASA’s SPHEREx (the Spectrophotometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) mission has been carrying out a groundbreaking infrared spectral survey of the entire sky at 6″ spatial resolution. The first full epoch

Searching for Supermassive Black Hole Binaries: Gas, Gravity, and Gravitational Waves At the center of nearly every galaxy in the Universe resides a supermassive black hole. When galaxies collide, their supermassive black holes sink to the center of the newly forming galaxy. There in this nascent galactic nucleus a supermassive black hole binary is formed.

Stress-Testing the Standard Cosmological Model The concordance cosmological model rests on three invisible pillars—dark matter, dark energy, and black holes—that together make up ~96% of the Universe, yet each remains fundamentally mysterious. We are witnessing a data-driven revolution in black hole astrophysics that is rapidly transforming our understanding of how black holes form, grow, and

Mapping Alien Worlds: from Infernal to Habitable Worlds  Although we will never get the same level of details for exoplanets as we do for Solar System bodies, the large diversity of exoplanets revealed by exoplanet hunting missions, e.g. Kepler and TESS, provide thousands of study cases to refine formation and evolution pathways as well as theories

A new view of the red and distant Universe from JWST/NIRSpec Abstract: In its three years of science operations, JWST has revolutionized our understanding of the early Universe. Arguably the most impressive leap forward has come from the NIRSpec instrument, providing a detailed view of the physical processes – star formation, feedback, and the growth

Pioneering Emission Mapping of the Circumgalactic Medium with Aspera: Mission Progress and Lessons Learned. For over half a century, observational astrophysics has sought to detect and map warm-hot phase ‘coronal’ gas in the circumgalactic medium (CGM), one of the most massive baryonic components of galaxies. Despite its importance to galaxy evolution, this gas phase remains

Thermonuclear X-ray Bursts: Probing Neutron Stars and a Double-Photospheric-Radius-Expansion Thermonuclear X-ray bursts observed from neutron stars originate from intermittent unstable nuclear burning of accreted matter on these stars. Such bursts, which significantly outshine the accretion-powered emission, are an excellent tool for probing the strong gravity and superdense matter, as well as for studying nuclear fusion,

History of the Intergalactic Medium Thermal History The thermal history of the intergalactic medium (IGM) is governed by the relatively simple physics of photoheating and cooling, and can be constrained using measurements from the Lyman-alpha forest. Over the past decade, these measurements have become much more precise. Unexpectedly, important theoretical advances have also emerged —

Title: Ergomagnetospheres, Ejection Disks and Wave Optics in M87 and SS433

Cosmic heavyweights: masses, host galaxies, and an origin story Abstract: Supermassive black holes (SMBHs) are ubiquitously found at the centers of massive galaxies near and far, and they likely played pivotal roles in shaping the co-evolution of galaxies and their central engines. Yet, the origins of SMBHs remain a mystery. Recent observational advancements have made significant

It Takes Two to Tango: Modeling Binary Stellar Populations in the Gravitational Wave Era Abstract: The field of astrophysics is in the midst of a golden age. Between the detection of gravitational waves from over a hundred merging compact objects, the commissioning of the James Webb Space Telescope which can see galaxies farther away and further

Using Tidal Disruption Events as Probes of Massive Black Hole Formation and Growth Over Cosmic Time The tidal disruption of a star that wanders too close to a central black hole is a unique probe of quiescent supermassive black holes lurking in the nuclei of galaxies. We have demonstrated the ability to discover and spectroscopically

What is JWST teaching us about the early Universe? The James Webb Space Telescope (JWST) is revolutionizing our understanding of the early universe, and in this talk I will explore how its observations fit — or don’t — within our cosmological and galaxy-formation models. First, I will discuss the unexpectedly high abundance of galaxies in

The Dynamical Evolution of Exoplanet Systems Over Billions of Years Exoplanet systems are expected to evolve with time as they age. In most cases though, the dynamical evolution of exoplanet systems over billion-year timescales are hard to directly observe. I’ll first describe the variety of ways that data from Gaia and/or the James Webb Space

Like most galaxies, the Milky Way harbors a supermassive black hole (SMBH) at its center, surrounded by a stellar cluster. In this densely populated environment, stars frequently collide and interact with one another. I will discuss the implications of these collisions and connect them to astrophysical puzzles observed at the very heart of our galaxy. Close

The x-ray sky in high definition: 25 years of astrophysics with the Chandra X-ray Observatory X-ray astronomy is a product of the space age. Possible only from viewing platforms above the atmosphere, the first celestial x-ray source other than the Sun was discovered just over sixty years ago. Following fresh on the heels of this