Astrophysics

Kirk Long and Constanza Echiburú‑Trujillo Receive 2026 R. N. Thomas Award

Steven Burrows — Fri, 24 Apr 2026 15:07:32 +0000

Kirk Long and Constanza Echiburú‑Trujillo Receive 2026 R. N. Thomas Award Steven Burrows Fri, 04/24/2026 - 09:07

Constanza Echiburú‑Trujillo and nominee Drake Miller III.

JILA is pleased to announce that graduate students Kirk Long and Constanza Echiburú‑Trujillo are the recipients of the 2026 Richard Nelson Thomas Award, which recognizes outstanding experimental contributions by JILA graduate students. This year’s nominees also included Drake Miller III and Sajal Gupta, highlighting the strength and breadth of graduate research across the institute.

Long was recognized for his contributions at JILA prior to beginning a postdoctoral appointment in Germany. Although he was unable to attend the award presentation in person, his work and engagement during his time at JILA exemplify the standards of excellence and collaboration the Thomas Award is meant to recognize.

Echiburú‑Trujillo was honored for her accomplishments as a JILA graduate student and her contributions to the JILA research community. In addition to her academic work, she has been an active and supportive presence within her group and the broader institute.

The R. N. Thomas Award is presented annually in memory of Richard Nelson Thomas, whose dedication to experimental science and graduate education left a lasting impact at JILA. The award recognizes students whose work and service reflect those values and who contribute meaningfully to JILA’s collaborative research environment.

Kirk Long.

Graduate students Kirk Long and Constanza Echiburú‑Trujillo have been awarded the 2026 Richard Nelson Thomas Award, an honor rooted in JILA’s astronomy tradition that recognizes outstanding experimental contributions by graduate students. Drake Miller III and Sajal Gupta were also nominated, underscoring the depth of student research across the institute.

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JILA Researchers Overturn 25-Year-Old Explanation of Benzene Formation in Space

Steven Burrows — Fri, 09 Jan 2026 18:21:00 +0000

JILA Researchers Overturn 25-Year-Old Explanation of Benzene Formation in Space Steven Burrows Fri, 01/09/2026 - 11:21

Bailey Bedford / Freelance Science Communicator

Interstellar formation of PAHs terminates at C6H5+. Image credit: Steven Burrows / JILA

Space is famously empty. The cold vacuum of space—or more specifically, the interstellar medium—lacks much of anything, including the air needed to conduct sound. But it isn’t quite completely empty. While it’s vacant compared to what we experience in daily life, there are occasional atoms and molecules spread throughout it.

Those atoms and molecules mean that there is chemistry in space, although it doesn’t always resemble the dense, warm reactions that routinely occur in a chemist’s test tubes. One aspect of chemistry in space that researchers are interested in is the formation of polycyclic aromatic hydrocarbons (PAHs), which are molecules of carbon and hydrogen that make a broad array of chemicals on earth and in the void of space. Researchers have seen signs of light interacting with a variety of these molecules in space and being absorbed—leaving a distinctive fingerprint in the remaining light that reaches Earth. These molecules are estimated to contain somewhere between a tenth and a quarter of the carbon spread across the interstellar medium, and the molecules’ foundational building blocks are benzene (C₆H₆)—a ring of six carbon atoms, each holding a hydrogen atom.

Since 1999, researchers have had a model that they thought explained how benzene formed from smaller molecules. However, the challenges of performing experiments at the low temperatures and densities involved in mimicking the conditions in the interstellar medium have meant that researchers have relied on their theoretical understanding of the process and haven’t thoroughly tested it in experiments.

Now, JILA Fellow and University of Colorado Boulder Physics Professor Heather Lewandowski and members of her lab have used tools developed in physics laboratories to recreate the necessary conditions and have investigated how the chemistry plays out. The team described their experiment in an article published in the journal Nature Astronomy in May 2025. When they tested the process, the first steps played out as expected, but then they were surprised to find that the benzene failed to form at the final step. Their results give scientists a new window into how chemistry occurs in the interstellar medium and reopens the question of how carbon gets caught up in PAHs throughout space.

The key to recreating the chemistry occurring in the interstellar medium was creating a vacuum in a chamber and using lasers to cool molecules and hold them in place in the vacated space. This required the researchers to look at just a small number of molecules and to set aside the beakers and test tubes that are stereotypical of chemistry and instead rely on large metal chambers, air pumps, laser beams and many mirrors and lenses.

“It's a laboratory full of lasers, and vacuum chambers, and optics,” Lewandowski says. “It fills up half a room to be able to cool down these hundred little molecules.”

Selecting the right color of laser and aligning the beams correctly allows the researchers to suspend—trap—particles in a vacuum chamber as well as cool them down through a process called laser cooling. Laser cooling relies on the fact that light can give atoms and molecules a shove to slow them down and that the interaction can be tailored to depend on how the particles are moving. Carefully applied, laser cooling can get molecules down to temperatures just above absolute zero.

“Laser cooling and trapping has really been in the domain of physicists,” Lewandowski says. “The nice thing about JILA is we have physicists and chemists working together. In my own group, we have both backgrounds, and so we have the tools now that can answer these questions that really chemists didn't have the technology to tackle and physicists didn't know it was an interesting question to answer.”

These techniques allow them to focus on a small number of molecules and get a close look at the interactions that normally are obscured in a chaos of many reactions occurring rapidly and simultaneously.

With the equipment creating the needed conditions, the group started following the proposed recipe for creating benzene in the interstellar medium. The recipe’s main ingredient is a molecule of two carbon atoms and two hydrogen atoms, called acetylene (C₂H₂). The first step is mixing acetylene with molecules containing two nitrogen atoms and one hydrogen atom (N₂H⁺). The nitrogen atoms can provide their hydrogen atom to create new molecules with two carbon and three hydrogen atoms. That opens the door to two more steps of interactions with acetylene molecules to produce a molecule with six carbon atoms and five hydrogen atoms (C₆H₅⁺)—just one hydrogen short of the target benzene ring. The exact behavior of this molecule is not thoroughly understood, but the established recipe proposed that it could form benzene by capturing a molecule made from a pair of hydrogens and then letting the excess atoms go.

The team supplied just enough of the needed ingredients in the chamber so that it was improbable that more than two molecules would be reacting at a time. Using laser cooling, they cooled the molecules in the chamber down to just a few degrees Kelvin. This setup let them recreate what happens when two lonely molecules finally come together in space and get the chance to interact.

The group repeatedly ran the experiment, stopping after different amounts of time to eject the cloud of molecules and check which molecules had been formed. They saw the mixture progress through the expected steps of the recipe. They observed increases of various molecules as they were created and then decreases as they were consumed in the construction of even larger molecules. But as they waited progressively longer and longer, they never caught sight of any benzene rings. The mixture in the chamber eventually just reached a steady amount of C₆H₅⁺, and the final step of the recipe failed to occur.

“Initially we were very confused—and a little irritated—because we could never get the final reaction to happen,” says JILA postdoctoral researcher G. Stephen Kocheril, the lead author of the paper.

After performing several runs of the experiment and analyzing the data, the team concluded that the expected chain of events wasn’t happening and there must be something else occurring to produce all the benzene in space.

“None of the models now actually predict what's out there,” Lewandowski says. “If you look at observations of how many of these molecules we have out there, no model works. So we sort of said, ‘this model isn't it.’ We don't have a new model yet; that's what we're working on now. So it was kind of big for the community because it changed how larger and larger carbon-containing molecules are formed in space.”

Moving beyond the old explanation gives chemists insights into how they should think about the formation of these molecules and provides astronomers with new clues about which molecules they should be keeping an eye out for if they want to understand the chemistry happening out in the interstellar medium.

JILA Fellow and University of Colorado Boulder Physics Professor Heather Lewandowski and members of her lab have shattered a 25-year-old theory about how benzene forms in the interstellar medium, revealing that the long-accepted chemical recipe doesn’t work under space-like conditions. Their groundbreaking laser-cooling experiments open a new chapter in understanding the origins of complex carbon molecules in the cosmos.

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JILA welcomes its newest Fellow, Dr. Taeho Ryu!

Steven Burrows — Mon, 18 Aug 2025 19:02:19 +0000

JILA welcomes its newest Fellow, Dr. Taeho Ryu! Steven Burrows Mon, 08/18/2025 - 13:02

Steven Burrows / JILA Science Communications Manager

Photo of Dr. Taeho Ryu.

JILA is delighted to welcome Dr. Taeho Ryu as an Associate Fellow and Assistant Professor in the Department of Astrophysical and Planetary Sciences at the University of Colorado Boulder.

Dr. Ryu brings a dynamic and interdisciplinary approach to theoretical astrophysics, with a research portfolio that spans the complex interactions between stars and black holes, the formation and evolution of dense stellar clusters, and the observational signatures of transient astrophysical phenomena. His work is deeply rooted in multi-messenger astronomy, exploring phenomena such as tidal disruption events, stellar collisions, and gravitational wave sources.

His recent efforts have focused on advancing our understanding of transient formation mechanisms beyond conventional models, particularly in environments shaped by complex gravitational interactions.

Before joining ��Ҵ�ý�ƽ�� and JILA, Dr. Ryu held a fellowship at the Max Planck Institute for Astrophysics in Garching, Germany. He earned his undergraduate degrees in Chemistry and Physics from Seoul National University, received a PhD from Stony Brook University, and completed his postdoc at Johns Hopkins University.

Outside of academia, Dr. Ryu is a passionate musician, tennis player, and snowboarder—bringing creativity and energy to both his research and personal pursuits.

We are thrilled to have Dr. Ryu join the JILA community and look forward to the exciting contributions he will make to our understanding of the transient universe.

JILA is delighted to welcome Dr. Taeho Ryu as an Associate Fellow and Assistant Professor in the Department of Astrophysical and Planetary Sciences at the University of Colorado Boulder.

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Trying to Solve a Key Black Hole Mystery: Simulating Magnetic Flows Around Black Holes

Steven Burrows — Tue, 18 Feb 2025 19:48:01 +0000

Trying to Solve a Key Black Hole Mystery: Simulating Magnetic Flows Around Black Holes Steven Burrows Tue, 02/18/2025 - 12:48

Kenna Hughes-Castleberry / JILA Science Communicator

Black holes have been fascinating subjects of study, not just because they are cosmic vacuum cleaners, but also as engines of immense power capable of extracting and redistributing energy on a staggering scale. These dark giants are often surrounded by swirling disks of gas and dust, known as accretion disks. When these disks are strongly magnetized, they can act like galactic power plants, extracting energy from the black hole’s spin in a process known as the Blandford-Znajek (BZ) effect.

While scientists have theorized that the BZ effect is the primary mechanism in the energy extraction process, many unknowns remain, like what determines how much energy is funneled into powerful jets—powerful streams of particles and energy ejected along the black hole's poles—or dissipated as heat.

To answer these questions, JILA postdoctoral researcher Prasun Dhang, and JILA Fellows and University of Colorado Boulder Astrophysical and Planetary Sciences professors Mitch Begelman and Jason Dexter, turned to advanced computer simulations. By modeling black holes surrounded by thin, highly magnetized accretion disks, they sought to uncover the underlying physics that drives these enigmatic systems. Their findings, published in The Astrophysical Journal, offer crucial insights into the complex physics around black holes and could redefine how we understand their role in shaping galaxies.

“It's long been known that infalling gas can extract spin energy from a black hole,” elaborates Dexter. “Usually, we assume this is important for powering jets. By making more precise measurements, Prasun has shown there's a lot more energy extracted than previously known. This energy could be radiated away as light, or it could cause gas to flow outwards. Either way, extracted spin energy could be an important energy source for lighting up the regions near the black hole event horizon.”

Comparing Black Hole to Black Hole

For decades, scientists have studied black holes and their interactions with surrounding gas and magnetic fields to understand how they power some of the universe’s most energetic phenomena. Early research focused primarily on low-luminosity black hole sources with quasi-spherical accretion flow as these systems are comparatively easier to simulate and align with many observed jets.

However, high-luminosity black holes with geometrically thinner, denser magnetized disks present a unique challenge. These systems are theoretically unstable due to imbalances in heating and cooling.

Artist render of a black hole surrounded by a highly magnetized thin disk. Image credit: Steven Burrows / JILA

However, previous studies, including those by Mitch Begelman, suggested that strong magnetic fields might stabilize these thin disks, but the details of their role in energy extraction and jet formation remained unclear in such conditions.

“We wanted to understand how energy extraction works in these highly magnetized environments,” Dhang explains.

Simulating Magnetized Flows Around Black Holes

The team used advanced computer simulations to explore this phenomenon, specifically, a special type of model called the 3D general relativistic magnetohydrodynamic (GRMHD) model. The GRMHD model works as a computational framework that simulates the behavior of magnetized plasma in the curved spacetime around black holes, combining the physics of magnetic fields, fluid dynamics, and Einstein's theory of general relativity to capture the complex interactions in these extreme environments. Using the framework, the researchers observed how magnetic fields interacted with black holes spinning at different speeds.

“The goal was to see how magnetic flux threading [permeating] the black hole impacts energy extraction and whether it leads to the formation of jets,” Dhang says.
The simulations modeled thin, magnetized accretion disks and examined how much energy the black hole transferred to its surroundings. By studying the efficiency of this energy extraction, the team identified various black hole spins and magnetic configurations with jets.

Manifestation of BZ power

From their simulations, the team found that depending on the black hole's spin, between 10% and 70% of the energy extracted through the BZ process was channeled into jets.

“The higher the spin, the more energy the black hole can release,” Dhang notes.

However, not all energy went into jets; some was absorbed back into the disk or dissipated as heat.

While the simulations couldn’t determine where the excess energy went, Dhang plans to study this further to better understand how jets form, as jets are often found in active galactic nuclei systems such as quasars.

Mysteries Continue

From their models, the researchers found that the strong magnetic fields increased the disk's radiative efficiency, making it brighter. This extra luminosity may explain why some black holes appear far more luminous than theoretical models predict.
“The unused energy close to the black hole could heat the disk and contribute to a corona,” Dhang notes.

The corona, a region of hot gas surrounding the black hole that emits intense x-rays, is crucial for shaping the light we observe from these systems, but its exact formation process remains unclear.

The researchers hope to use further simulations to understand the dynamics of making a black hole corona.

This work was supported by the National Science Foundation, the NASA Astrophysics Theory Program, and the Alfred P. Sloan Fellowship.

JILA postdoctoral researcher Prasun Dhang, and JILA Fellows and University of Colorado Boulder Astrophysical and Planetary Sciences professors Mitch Begelman and Jason Dexter, turned to advanced computer simulations to model black holes surrounded by thin, highly magnetized accretion disks, to uncover the underlying physics that drives these enigmatic systems. Their findings, published in The Astrophysical Journal, offer crucial insights into the complex physics around black holes and could redefine how we understand their role in shaping galaxies.

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JILA Fellow and University of Colorado Boulder APS Distinguished Professor Mitch Begelman Inducted as 2025 AAS Fellow, Joining APS Professors James Green and J. Michael Shull in Prestigious Recognition

Steven Burrows — Mon, 13 Jan 2025 17:44:12 +0000

JILA Fellow and University of Colorado Boulder APS Distinguished Professor Mitch Begelman Inducted as 2025 AAS Fellow, Joining APS Professors James Green and J. Michael Shull in Prestigious Recognition Steven Burrows Mon, 01/13/2025 - 10:44

Kenna Hughes-Castleberry / JILA Science Communicator

Mitchell Begelman. Image credit: Glenn Asakawa, 2020.

JILA Fellow and the Department of Astrophysical and Planetary Sciences (APS) at the University of Colorado Boulder Distinguished Professor Mitch Begelman has been inducted as a 2025 American Astronomical Society (AAS) Fellow. Joining Professor Begelman in this recognition are APS Professors James Green and J. Michael Shull, now an Adjunct Professor of Physics and Astronomy at the University of North Carolina, Chapel Hill. Together, their contributions underscore ��Ҵ�ý�ƽ�� leadership in astrophysics and planetary sciences.

Professor Begelman was honored for his pioneering analytical and computational studies of high-energy astrophysical phenomena, including developing the “quasi-star theory” explaining the formation of supermassive black holes. His dedication to public engagement has further enriched the public’s understanding of black holes through two acclaimed books.

“I am deeply honored to be recognized by the AAS and to share this distinction with my esteemed colleagues,” said Begelman. “This recognition reflects the collaborative spirit of research at ��Ҵ�ý�ƽ�� and JILA, where groundbreaking ideas flourish.”

Green was commended for his exceptional contributions to ultraviolet space astronomy and his role in advancing spectrograph designs that have enabled groundbreaking discoveries.
Meanwhile, Shull was recognized for his theoretical modeling and observational studies that have provided transformative insights into intergalactic and interstellar gas.

“It’s wonderful to see that ��Ҵ�ý�ƽ�� APS department had three of the 24 AAS Fellows awarded this year,” Shull stated.

These accolades reflect the tireless dedication of all three researchers to advancing astrophysics and mentoring the next generation of scientists.

��Ҵ�ý�ƽ�� and JILA celebrate this recognition of Professors Begelman, Green, and Shull, whose achievements continue to inspire and elevate the global astronomy community.

Read the full AAS announcement here.

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JILA Graduate Student Tatsuya Akiba Awarded 2024 Richard Nelson Thomas Award

Steven Burrows — Fri, 26 Jul 2024 19:24:17 +0000

JILA Graduate Student Tatsuya Akiba Awarded 2024 Richard Nelson Thomas Award Steven Burrows Fri, 07/26/2024 - 13:24

Kenna Hughes-Castleberry / JILA Science Communicator

JILA graduate student Tatsuya Akiba (left) celebrates with advisor JILA Fellow and Astrophysical and Planetary Sciences Associate Professor Ann-Marie Madigan. Credit: Kenna Hughes-Castleberry/JILA

"Receiving an award named after R. N. Thomas, a notable astrophysicist and one of the founding members of JILA, means a lot to me," Akiba mentioned. "JILA has hosted and trained many successful astrophysicists in the past and present, so it is a great honor to be named the astrophysics graduate student of the year at such a prestigious institution."

This honor is bestowed annually to an outstanding APS graduate student at JILA and recognizes excellence in research and academic achievements.

“Tatsuya is an enthusiastic researcher, educator, and mentor,” said JILA Fellow and Associate Professor of Astrophysical & Planetary Sciences Ann-Marie Madigan, who advises Akiba. “He won the ��Ҵ�ý�ƽ�� Award for Excellence in Teaching in 2021. Last semester, he taught an undergraduate course on Python coding. He has served as a mentor for CU Prime, a graduate peer mentor, and the McNair programs, and he has advised several undergraduates.”

Akiba reciprocated Madigan's compliments by stating: "I couldn’t have done it without the help of Ann-Marie Madigan, who I’ve been lucky enough to work with for four years now. My research progress wouldn’t have been possible without an advisor who cares just as much as (probably even more than) me about the weird orbits of stars and planets - just look at the chalkboard in her office if you ever get the chance. In all seriousness, though, thank you to the award’s committee members, Ann-Marie, and the other members of the Madigan Group for all of your support!"

Akiba and Madigan study the gravitational dynamics of bodies in orbit around compact objects. Their current work delves into the dynamics of eccentric disks in various astrophysical contexts, including stars orbiting supermassive black holes and planetesimals around white dwarfs.

This award highlights Akiba's significant contributions to the field and underscores the innovative research being conducted at JILA. Congratulations to Tatsuya Akiba for this well-deserved recognition!

JILA graduate student Tatsuya Akiba, a Ph.D. candidate in the Astrophysical & Planetary Sciences department at the University of Colorado Boulder, has received the prestigious 2024 Richard Nelson Thomas Award. This honor is bestowed annually to an outstanding APS graduate student at JILA and recognizes excellence in research and academic achievements.

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Hungry, Hungry White Dwarfs: Solving the Puzzle of Stellar Metal Pollution

Steven Burrows — Fri, 03 May 2024 17:11:35 +0000

Hungry, Hungry White Dwarfs: Solving the Puzzle of Stellar Metal Pollution Steven Burrows Fri, 05/03/2024 - 11:11

Kenna Hughes-Castleberry / JILA Science Communicator

Planetesimal orbits around a white dwarf. Initially, every planetesimal has a circular, prograde orbit. The kick forms an eccentric debris disk which with prograde (blue) and retrograde orbits (orange). Image Credit: Steven Burrows / JILA

Despite their prevalence, the chemical makeup of these stellar remnants has been a conundrum for astronomers for years. The presence of heavy metal elements—like silicon, magnesium, and calcium—on the surface of many of these compact objects is a perplexing discovery that defies our expectations of stellar behavior.

“We know that if these heavy metals are present on the surface of the white dwarf, the white dwarf is dense enough that these heavy metals should very quickly sink toward the core,” explains JILA graduate student Tatsuya Akiba. “So, you shouldn't see any metals on the surface of a white dwarf unless the white dwarf is actively eating something.”

While white dwarfs can consume various nearby objects, such as comets or asteroids (known as planetesimals), the intricacies of this process have yet to be fully explored. However, this behavior could hold the key to unraveling the mystery of a white dwarf's metal composition, potentially leading to exciting revelations about white dwarf dynamics.

In results reported in a new paper in The Astrophysical Journal Letters, Akiba, along with JILA Fellow and University of Colorado Boulder Astrophysical and Planetary Sciences professor Ann-Marie Madigan and undergraduate student Selah McIntyre, believe they have found a reason why these stellar zombies eat their nearby planetesimals. Using computer simulations, the researchers simulated the white dwarf receiving a “natal kick” during its formation (which has been observed) caused by asymmetric mass loss, altering its motion and the dynamics of any surrounding material.

In 80% of their test runs, the researchers observed that, from the kick, the orbits of comets and asteroids within a range of 30 to 240 AU of the white dwarf (corresponding to the Sun–Neptune distance and beyond) became elongated and aligned. Furthermore, around 40% of subsequently eaten planetesimals come from counter-rotating (retrograde) orbits.

The researchers also extended their simulations to examine the white dwarf's dynamics after 100 million years. They found that the white dwarf’s nearby planetesimals still had elongated orbits and moved as one coherent unit, a result never seen before.

“This is something I think is unique about our theory: we can explain why the accretion events are so long-lasting,” states Madigan. “While other mechanisms may explain an original accretion event, our simulations with the kick show why it still happens hundreds of millions of years later.”
These results explain why the heavy metals are found on the surface of a white dwarf, as that white dwarf continuously consumes smaller objects in its path.

It’s All ��Ҵ�ý�ƽ�� Gravity

As Madigan’s research group at JILA focuses on gravitational dynamics, looking at the gravity surrounding white dwarfs seemed like a natural focus of study.

“Simulations help us understand the dynamics of different astrophysical objects,” Akiba says. “So, in this simulation, we throw a bunch of asteroids and comets around the white dwarf, which is significantly bigger, and see how the simulation evolves and which of these asteroids and comets the white dwarf eats.”

The researchers hope to take their simulations to greater scales in future projects, looking at how white dwarfs interact with larger planets.

As Akiba elaborates, “Other studies have suggested that asteroids and comets, the small bodies, might not be the only source of metal pollution on the white dwarf’s surface. So, the white dwarfs might eat something bigger, like a planet.”

Discovering More about Solar System Formation

These new findings further reveal more about the formation of white dwarfs, which is important in understanding how solar systems change over millions of years. They also help shed light on the origins and future evolution of our solar system, revealing more about the chemistry involved.

“The vast majority of planets in the universe will end up orbiting a white dwarf,” Madigan says. “It could be that 50% of these systems get eaten by their star, including our own solar system. Now, we have a mechanism to explain why this would happen.”

“Planetesimals can give us insight into other solar systems and planetary compositions beyond where we live in our solar region” McIntyre adds. “White dwarfs aren't just a lens into the past. They're also kind of a lens into the future.”

Dead stars known as white dwarfs, have a mass like the Sun while being similar in size to Earth. They are common in our galaxy, as 97% of stars are white dwarfs. As stars reach the end of their lives, their cores collapse into the dense ball of a white dwarf, making our galaxy seem like an ethereal graveyard.

Despite their prevalence, the chemical makeup of these stellar remnants has been a conundrum for astronomers for years. The presence of heavy metal elements—like silicon, magnesium, and calcium—on the surface of many of these compact objects is a perplexing discovery that defies our expectations of stellar behavior.

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JILA Fellow and Astrophysical and Planetary Sciences Professor Mitch Begelman is Elected to the National Academy of Sciences

Steven Burrows — Tue, 30 Apr 2024 17:28:12 +0000

JILA Fellow and Astrophysical and Planetary Sciences Professor Mitch Begelman is Elected to the National Academy of Sciences Steven Burrows Tue, 04/30/2024 - 11:28

Kenna Hughes-Castleberry / JILA Science Communicator

Mitchell Begelman. Image credit: Glenn Asakawa, 2020.

JILA is thrilled to announce that Dr. Mitch Begelman, a JILA Fellow and esteemed professor in the Department of Astrophysical and Planetary Sciences at the University of Colorado Boulder, has been elected as a member of the National Academy of Sciences. This prestigious honor is bestowed in recognition of his distinguished and ongoing contributions to original research in astrophysics.

The National Academy of Sciences, which announced the election of 120 new members and 24 international members this year, selects individuals who have achieved significant accomplishments in their respective scientific fields.

Begelman's inclusion in this elite group brings the total number of active members to 2,617 and international members to 537, emphasizing the Academy's commitment to excellence and scientific advancement.

Begelman's research primarily explores the frontiers of theoretical and high-energy astrophysics, focusing on the dynamics of black holes and their energy outputs. His pioneering work has significantly advanced the understanding of how black holes influence their surrounding environments and contribute to the broader structure of the universe.

The election of Begelman to the National Academy of Sciences not only honors his individual achievements but also highlights JILA's and the University of Colorado Boulder's role as leading institutions in astrophysical research.

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Remembering JILA Fellow and Founding Member, Astrophysicist Peter Bender

Steven Burrows — Mon, 22 Apr 2024 17:30:03 +0000

Remembering JILA Fellow and Founding Member, Astrophysicist Peter Bender Steven Burrows Mon, 04/22/2024 - 11:30

Kenna Hughes-Castleberry / JILA Science Communicator

Peter L. Bender

As a JILA Fellow from 1963 to 1995 and later a Fellow Adjoint, Bender was deeply and actively involved in pioneering research that has shaped our understanding of the universe.

Born in New York, Bender's early passion for math and physics propelled him to pursue an undergraduate degree at Rutgers University, followed by graduate degrees at Princeton, where he was influenced by the notable physicist Robert Dicke. Bender's dissertation on the optical pumping of sodium vapor laid the groundwork for a career that would blend rigorous experimental physics with theoretical insights, always aimed at pushing the boundaries of what we understand about physical measurements and astrophysical phenomena.

Bender's tenure at JILA began in the 1960s, after a productive period at the National Bureau of Standards (now NIST), where he focused on precision measurements and magnetic fields. His work at JILA quickly pivoted towards the astrophysical, culminating in a significant role in the Apollo missions' Lunar Laser Ranging Experiment. This collaboration included scientists like Dr. James Faller, another early member and Fellow of JILA. This experiment involved placing retroreflectors on the moon, which are still used to measure the distance between the Earth and the moon with extraordinary precision.

Beyond his lunar research, Bender's contributions extended into other areas of astrophysics and geophysics. Over four decades, he developed the conceptual design and scientific justification for the LISA project (Laser Interferometer Space Antenna), a space mission for detecting gravitational waves, a key prediction of Einstein's theory of general relativity. His work and stewardship helped pave the way for this field's future explorations and have impacted how we perceive phenomena in deep space.

In geophysics, Bender applied his expertise in precision measurement to study the Earth's gravitational field, contributing to gravity mapping missions like GRACE (Gravity Recovery and Climate Experiment) and its successors. These missions monitor variations in Earth's gravity, which have implications for studying water reserves, sea level rise, and climate change.

Throughout his career, Bender was not just a mentor but a true collaborator to many in the scientific community. He was known for his quiet yet profound ability to question and refine existing theories and experiments, pushing scientific inquiry further with each project. His advisory roles for NASA, the National Academy of Sciences, and the National Research Council underscored his commitment to science and its advancement.

Bender's legacy is not only marked by his scientific achievements but also by his deep philosophical engagement with the implications of science for society. He believed strongly in the power of scientific inquiry to contribute positively to the world. Still, he remained acutely aware of the broader social and economic contexts in which scientific work is embedded.

As we remember Peter Bender, we reflect on a career that epitomized the pursuit of knowledge and the application of that knowledge to solve real-world problems. His work continues to inspire a new generation of scientists at JILA and beyond, ensuring that his contributions to astrophysics and precision measurement will endure in the scientific community for decades.

Dr. Peter L. Bender, an esteemed experimental physicist and a foundational member of JILA (formerly the Joint Institute for Laboratory Astrophysics) at the University of Colorado Boulder, passed away recently, leaving behind a legacy marked by significant contributions to the fields of geophysics, astrophysics, and precision measurement.

As a JILA Fellow from 1963 to 1995 and later a Fellow Adjoint, Bender was deeply and actively involved in pioneering research that has shaped our understanding of the universe.

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JILA Undergraduate Research Assistant Aaron Barrios is Awarded a 2024 Jacob Van Ek Scholarship

Steven Burrows — Fri, 19 Apr 2024 17:34:07 +0000

JILA Undergraduate Research Assistant Aaron Barrios is Awarded a 2024 Jacob Van Ek Scholarship Steven Burrows Fri, 04/19/2024 - 11:34

Kenna Hughes-Castleberry / JILA Science Communicator

Undergraduate research assistant Aaron Barrios

JILA undergraduate student Aaron Barrios has recently been honored with the prestigious Jacob Van Ek Scholarship, an accolade from the University of Colorado Boulder College of Arts and Sciences to a select group of exceptional undergraduates. This year, Barrios is among 23 distinguished students to receive one of the college's highest honors, reflecting his outstanding contributions and academic excellence in Physics, Astronomy, and Mathematics.

The scholarship is named after Jacob Van Ek, who profoundly impacted CU’s academic landscape. Van Ek, born in 1896, began his illustrious career at CU shortly after completing his doctorate in 1925 at what is now Iowa State University. He quickly ascended from an assistant professor to a full professor within a mere three years and served as the dean of the College of Liberal Arts from 1929 to 1959. His legacy continues to inspire and recognize student excellence through this scholarship.

Aaron Barrios's research, under the mentorship of JILA Fellow and Astrophysical & Planetary Sciences professor Jason Dexter, focuses on the intriguing dynamics of black holes and accretion disk theory. Barrios' work primarily investigates how isotropic emissions around black holes can become anisotropic, a critical study in understanding the behavior of light and radiation in extreme gravitational fields.

JILA undergraduate student Aaron Barrios has recently been honored with the prestigious Jacob Van Ek Scholarship, an accolade conferred by the University of Colorado Boulder College of Arts and Sciences to a select group of exceptional undergraduates. This year, Barrios is among 23 distinguished students to receive one of the college's highest honors, reflecting his outstanding contributions and academic excellence in the fields of Physics, Astronomy, and Mathematics.

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Astrophysics

Kirk Long and Constanza Echiburú‑Trujillo Receive 2026 R. N. Thomas Award

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JILA Researchers Overturn 25-Year-Old Explanation of Benzene Formation in Space

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JILA welcomes its newest Fellow, Dr. Taeho Ryu!

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Trying to Solve a Key Black Hole Mystery: Simulating Magnetic Flows Around Black Holes

Comparing Black Hole to Black Hole

Simulating Magnetized Flows Around Black Holes

Manifestation of BZ power

Mysteries Continue

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JILA Fellow and University of Colorado Boulder APS Distinguished Professor Mitch Begelman Inducted as 2025 AAS Fellow, Joining APS Professors James Green and J. Michael Shull in Prestigious Recognition

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JILA Graduate Student Tatsuya Akiba Awarded 2024 Richard Nelson Thomas Award

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Hungry, Hungry White Dwarfs: Solving the Puzzle of Stellar Metal Pollution

It’s All ���Ҵ�ý�ƽ������ Gravity

Discovering More about Solar System Formation

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JILA Fellow and Astrophysical and Planetary Sciences Professor Mitch Begelman is Elected to the National Academy of Sciences

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Remembering JILA Fellow and Founding Member, Astrophysicist Peter Bender

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JILA Undergraduate Research Assistant Aaron Barrios is Awarded a 2024 Jacob Van Ek Scholarship

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It’s All ��Ҵ�ý�ƽ�� Gravity