Juna Kollmeier’s research is an unusual combination—she is as observationally-oriented theorist making predictions that can be compared to current and future observations. Her primary focus is on the emergence of structure in the universe. She combines cosmological hydrodynamic simulations and analytic theory to figure out how the tiny fluctuations in density that were present when the universe was only 300 thousand years old, become the galaxies and black holes that we see now, after 14 billion years of cosmic evolution. 

 She has a three-pronged approach to unravelling the mysteries of the universe. On the largest scales, she studies the intergalactic medium (IGM)—the tenuous material of gas and dust in intergalactic space.  This is where most of the elementary particles in the universe reside and is the basis from which galaxies and stars form. It is both the source of star formation and the sink of the biproducts of star formation. Since it is mostly hydrogen, it is also the part of cosmological simulations that is understood best, which makes the IGM a very powerful tool to study galaxy growth and evolution.

On the intermediate scale, Kollmeier studies our Milky Way galaxy, which provides a laboratory for understanding the phenomena nearby that also exists in the distant universe. On the smallest scale, she studies supermassive black holes.  These energy spewing entities lie at the heart of all galaxies wreaking havoc on their galactic hosts. She is interested in how they grow, what the distribution of fundamental properties is, and how do they interact with their environments.

Kollmeier received a B.S. in physics from California Institute of Technology and a  Ph.D. in astronomy from Ohio State University. Before joining the Carnegie staff in 2008, she was a Hubble Fellow and

a Carnegie-Princeton postdoctoral fellow. For more information see   http://users.obs.carnegiescience.edu/jak/Research.html

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Called the Hubble Ultra Deep Field, this galaxy-studded view represents a "deep" core sample of the universe, cutting across billions of light-years. Courtesy: NASA, ESA, and S. Beckwith (STScI) and the HUDF Team
March 19, 2018

In the days after the death of Stephen Hawking, some of our scientists reflected on meeting him, on his contributions to science and science communication, and his impact on humanity. 


"I met Stephen Hawking in the winter of 1973-74 when I was a graduate student in physics at UC Santa Barbara. Hawking was already confined to a motorized wheel chair, though he could speak without a voice synthesizer. He gave a seminar about the work that he was doing with UCSB physics professor James B. Hartle. That collaboration led to their discovery that under certain circumstances, a black hole could emit radiation, as a result of quantum

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, Roberto Marcos Molar
February 26, 2018

Washington, DC—A team of astronomers led by Carnegie’s Meredith MacGregor and Alycia Weinberger detected a massive stellar flare—an energetic explosion of radiation—from the closest star to our own Sun, Proxima Centauri, which occurred last March. This finding, published by The Astrophysical Journal Letters, raises questions about the habitability of our Solar System’s nearest exoplanetary neighbor, Proxima b, which orbits Proxima Centauri.

MacGregor, Weinberger and their colleagues—the Harvard-Smithsonian Center for Astrophysics’ David Wilner and Adam Kowalski and Steven Cranmer of the University of Colorado Boulder—discovered the enormous flare when they reanalyzed observations

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, European Southern Observatory
February 8, 2018

Pasadena, CA— A star about 100 light years away in the Pisces constellation, GJ 9827, hosts what may be one of the most massive and dense super-Earth planets detected to date, according to new research led by Carnegie’s Johanna Teske. This new information provides evidence to help astronomers better understand the process by which such planets form.

The GJ 9827 star actually hosts a trio of planets, discovered by NASA’s exoplanet-hunting Kepler/K2 mission, and all three are slightly larger than Earth. This is the size that the Kepler mission determined to be most common in the galaxy with periods between a few and several-hundred-days.

Intriguingly, no planets of this size

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, NASA, Larry Nittler
January 18, 2018

Washington, DC— Dust is everywhere—not just in your attic or under your bed, but also in outer space. To astronomers, dust can be a nuisance by blocking the light of distant stars, or it can be a tool to study the history of our universe, galaxy, and Solar System.

For example, astronomers have been trying to explain why some recently discovered distant, but young, galaxies contain massive amounts of dust. These observations indicate that type II supernovae—explosions of stars more than ten times as massive as the Sun—produce copious amounts of dust, but how and when they do so is not well understood.

New work from a team of Carnegie cosmochemists published by Science

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The fund supports a postdoctoral fellowship in astronomy that rotates between the Carnegie Science departments of Terrestrial Magnetism in Washington, D.C., and the Observatories in Pasadena California. 

The Earthbound Planet Search Program has discovered hundreds of planets orbiting nearby stars using telescopes at Lick Observatory, Keck Observatory, the Anglo-Australian Observatory, Carnegie's Las Campanas Observatory, and the ESO Paranal Observatory.  Our multi-national team has been collecting data for 30 years, using the Precision Doppler technique.  Highlights of this program include the detection of five of the first six exoplanets, the first eccentric planet, the first multiple planet system, the first sub-Saturn mass planet, the first sub-Neptune mass planet, the first terrestrial mass planet, and the first transit planet.Over the course of 30 years we have improved the

The Giant Magellan Telescope will be one member of the next class of super giant earth-based telescopes that promises to revolutionize our view and understanding of the universe. It will be constructed in the Las Campanas Observatory in Chile. Commissioning of the telescope is scheduled to begin in 2021.

The GMT has a unique design that offers several advantages. It is a segmented mirror telescope that employs seven of today’s largest stiff monolith mirrors as segments. Six off-axis 8.4 meter or 27-foot segments surround a central on-axis segment, forming a single optical surface 24.5 meters, or 80 feet, in diameter with a total collecting area of 368 square meters. The GMT will

Along with Alycia Weinberger and Ian Thompson, Alan Boss has been running the Carnegie Astrometric Planet Search (CAPS) program, which searches for extrasolar planets by the astrometric method, where the planet's presence is detected indirectly through the wobble of the host star around the center of mass of the system. With over eight years of CAPSCam data, they are beginning to see likely true astrometric wobbles beginning to appear. The CAPSCam planet search effort is on the verge of yielding a harvest of astrometrically discovered planets, as well as accurate parallactic distances to many young stars and M dwarfs. For more see  http://instrumentation.obs.carnegiescience.edu/ccd/caps.

Guoyin Shen's research interests lie in the quest to establish and to examine models for explaining and controlling the behavior of materials under extreme conditions. His research activities include investigation of phase transformations and melting lines in molecular solids, oxides and metals; polyamorphism in liquids and amorphous materials; new states of matter and their emergent properties under extreme conditions; and the development of enabling high-pressure synchrotron techniques for advancing compression science. 

He obtained a Ph.D. in mineral physics from Uppsala University, Sweden in 1994 and a B.S. in geochemistry from Zhejiang University, China in 1982. For more

Leopoldo Infante became the director of the Las Campanas Observatory on July 31, 2017.

Since 2009, Infante has been the founder and director of the Centre for Astro-Engineering at the Chilean university. He joined PUC as an assistant professor in 1990 and has been a full professor since 2006. He was one of the creators of PUC’s Department of Astronomy and Astrophysics, and served as its director from 2000 to 2006. He also established the Chilean Astronomical Society (SOCHIAS) and served as its president from 2009 to 2010.

Infante received his B.Sc. in physics at PUC. He then acquired a MSc. and Ph.D. in physics and astronomy from the University of Victoria in Canada.

Guillermo Blanc wants to understand the processes by which galaxies form and evolve over the course of the history of the universe. He studies local galaxies in the “present day” universe as well as very distant and therefore older galaxies to observe the early epochs of galaxy evolution. Blanc conducts a series of research projects on the properties of young and distant galaxies, the large-scale structure of the universe, the nature of Dark Energy—the mysterious repulsive force, the process of star formation at galactic scales, and the measurement of chemical abundances in galaxies.

To conduct this work, he takes a multi-wavelength approach including observations in the UV,

Peter van Keken studies the thermal and chemical evolution of the Earth. In particularly he looks at the causes and consequences of plate tectonics; element modeling of mantle convection,  and the dynamics of subduction zones--locations where one tectonic plate slides under another. He also studies mantle plumes; the integration of geodynamics with seismology; geochemistry and mineral physics. He uses parallel computing and scientific visualization in this work.

He received his BS and Ph D from the University of Utrecht in The Netherlands. Prior to joining Carnegie he was on the faculty of the University of Michigan.