Astronomy Stories
November 6, 2014 Inflationary cosmology gives a very plausible explanation for many features of our universe, including its uniformity, its mass density, and the patterns of the ripples that are...
Explore this Story
Astronomer and photographer Yuri Beletsky captured today's lunar eclipse from Carnegie's Las Campanas Observatory...
Explore this Story
September 29, 2014 An AxS Festival Programpresented by The Carnegie Observatories and Pasadena Conservatory of MusicAxS [ak-sis] is a two-week citywide festival produced by the Pasadena Arts Council...
Explore this Story
AudioWashington, D.C.—New modeling studies from Carnegie’s Alan Boss demonstrate that most of the stars we see were formed when unstable...
Explore this Story
AudioPasadena, CA—Quasars are supermassive black holes that live at the center of distant massive galaxies. They shine as the most luminous...
Explore this Story
Washington, D.C.—A team of scientists led by Carnegie's Jacqueline Faherty has discovered the first evidence of water ice clouds on an...
Explore this Story
Pasadena, CA —The board of directors of the Giant Magellan Telescope Organization (GMTO) has informed the National Science Foundation (NSF) that they will not participate in an upcoming funding...
Explore this Story
Carnegie Institution Observatories researchers are featured in Astronomy Magazine discussing dark...
Explore this Story


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...
Explore this Project
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...
Explore this Project
The Carnegie-Spitzer-IMACS (CSI) survey, currently underway at the Magellan-Baade 6.5m telescope in Chile, has been specifically designed to characterize normal galaxies and their environments at a distance of about 4 billion years post Big Bang, expresses by astronomers as  z=1.5. The survey...
Explore this Project
The entire universe—galaxies, stars, and planets—originally condensed from a vast network of tenuous, gaseous filaments, known as the intergalactic medium, or the gaseous cosmic web. Most of the matter in this giant reservoir has never been incorporated into galaxies; it keeps floating about in...
Meet this Scientist
Some 40 thousand tons of extraterrestrial material fall on Earth every year. This cosmic debris provides cosmochemist Conel Alexander with information about the formation of the Solar System, our galaxy, and perhaps the origin of life. Alexander studies meteorites to determine what went on before...
Meet this Scientist
Staff astronomer emeritus Eric Persson headed a group that develops and uses telescope instrumentation to exploit new near-infrared (IR) imaging array detectors. The team built a wide-field survey camera for the du Pont 2.5-meter telescope at Carnegie’s Las Campanas Observatory in Chile, and the...
Meet this Scientist
You May Also Like...
Pasadena, CA— A team of astronomers including Carnegie’s Ian Thompson have managed to improve the measurement of the distance to our nearest neighbor galaxy and, in the process, refine an...
Explore this Story
It’s the celestial equivalent of a horror movie villain—a star that wouldn’t stay dead. An international team of astronomers including Carnegie’s Nick Konidaris and Benjamin Shappee discovered a star...
Explore this Story
On August 17, a team of four Carnegie astronomers provided the first-ever glimpse of two neutron stars colliding, opening the door to a new era of astronomy. Along with colleagues at UC Santa Cruz,...
Explore this Story

Explore Carnegie Science

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

January 9, 2018

National Harbor, MD—How far away is that galaxy? 

Our entire understanding of the Universe is based on knowing the distances to other galaxies, yet this seemingly-simple question turns out to be fiendishly difficult to answer. The best answer came more than 100 years ago from an astronomer who was mostly unrecognized in her time—and today, another astronomer has used Sloan Digital Sky Survey (SDSS) data to make those distance measurements more precise than ever. 

"It's been fascinating to work with such historically significant stars," says Kate Hartman, an undergraduate from Pomona College who announced the results at today’s American Astronomical Society (AAS) meeting in

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, Sloan Digital Sky Survey, SDSS-IV
January 9, 2018

National Harbor, MD—Astronomers with the Sloan Digital Sky Survey (SDSS) have learned that the chemical composition of a star can exert unexpected influence on its planetary system—a discovery made possible by an ongoing SDSS survey of stars seen by NASA's Kepler spacecraft, and one that promises to expand our understanding of how extrasolar planets form and evolve.

"Without these detailed and accurate measurements of the iron content of stars, we could have never made this measurement," says Robert Wilson, a graduate student in astronomy at the University of Virginia and lead author of the paper announcing the results.

The team presented their results today at the American

April 9, 2018

What is the Universe made of? We can peer millions of years into the past in the night sky, yet we barely understand just 5 percent—the “regular” matter that we can see. In the standard cosmological model, a quarter of the remaining 95 percent is dark matter. Dr. Seidel will discuss her quest to understand dark matter, and her experiences bringing astronomy education to some of the most remote and under-served locations on Earth.

Dr. Marja K. Seidel: Postdoctoral Research Associate, Carnegie Observatories


Carnegie Science, Carnegie Institution, Carnegie Institution for Science, John Mulchaey
April 19, 2018

From the work of luminaries Edwin Hubble and Vera Rubin to the recent detection of a neutron star merger and the discovery of the most-distant black hole, Carnegie scientists have played a central role in our understanding of the universe. Dr. Mulchaey will describe how Carnegie’s early telescopes at Mt. Wilson helped launch modern astronomy and how astronomers are using our current facilities in Chile to address some of the biggest mysteries of the universe. Finally, he will describe his efforts to build the next-generation Giant Magellan Telescope.

Dr. John Mulchaey: Interim Co-President, Carnegie Science; Director and Crawford H. Greenewalt Chair, Carnegie Observatories

May 21, 2018

As Carl Sagan once said, "We are made of star stuff." However, each element has its own astronomical origins story. Elements are created everywhere from the centers of stars, to supernovae explosions, to the Big Bang itself. Dr. Drout will take us on a journey through the periodic table, highlighting how our recent discovery of a 'kilonova' associated with the cataclysmic merger of two neutron stars has filled in one of the final pieces of the elemental puzzle—the origin of many of the heaviest elements in the universe.

Maria Drout: Hubble, Carnegie-Dunlap Fellow, Carnegie Observatories


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 Carnegie Hubble program is an ongoing comprehensive effort that has a goal of determining the Hubble constant, the expansion rate of the universe,  to a systematic accuracy of 2%. As part of this program, astronomers are obtaining data at the 3.6 micron wavelength using the Infrared Array Camera (IRAC) on Spitzer Space Telescope. The team has demonstrated that the mid-infrared period-luminosity relation for Cepheids, variable stars used to determine distances and the rate of the expansion,  at 3.6 microns is the most accurate means of measuring Cepheid distances to date. At 3.6 microns, it is possible to minimize the known remaining systematic uncertainties in the Cepheid

The Carnegie Irvine Galaxy Survey is obtaining high-quality optical and near-infrared images of several hundred of the brightest galaxies in the southern hemisphere sky, at Carnegie’s Las Campanas Observatory to investigate the structural properties of galaxies. For more see

The Carnegie-Spitzer-IMACS (CSI) survey, currently underway at the Magellan-Baade 6.5m telescope in Chile, has been specifically designed to characterize normal galaxies and their environments at a distance of about 4 billion years post Big Bang, expresses by astronomers as  z=1.5.

The survey selection is done using the Spitzer Space Telescope Legacy fields, which provides as close a selection by stellar mass as possible.

Using the IMACS infrared camera, the survey goal is to study galaxies down to low light magnitudes. The goal is to reduce the variance in the density of massive galaxies at these distances and times to accurately trace the evolution of the galaxy mass

John Mulchaey, director of the Observatories, serves as co-interim president of Carnegie as of January 1, 2018. He investigates groups and clusters of galaxies, elliptical galaxies, dark matter—the invisible material that makes up most of the universe—active galaxies and black holes. He is also a scientific editor for The Astrophysical Journal and is actively involved in public outreach and education.

Most galaxies including our own Milky Way, exist in collections known as groups, which are the most common galaxy systems and are important laboratories for studying galaxy formation and evolution. Mulchaey studies galaxy groups to understand the processes that affect most galaxies

We are all made of stardust. Almost all of the chemical elements were produced by nuclear reactions in the interiors of stars. When a star dies a fraction of the elements is released into the inter-stellar gas clouds, out of which successive generations of stars form.

 Astronomers have a basic understanding of this chemical enrichment cycle, but chemical evolution and nulceosynthesis are still not fully understood. Andrew McWilliam measures the detailed chemical composition of Red Giant stars, which are about as old as the galaxy and retain their original chemical composition.  He is seeking answer to questions such as: What are the sites of nucleosynthesis? What modulates element

Director Emeritus, George Preston has been deciphering the chemical evolution of stars in our Milky Way for a quarter of a century. He and Steve Shectman started this quest using a special technique to conduct a needle-in-the-haystack search for the few, first-generation stars, whose chemical compositions sketch the history of element formation in the galaxy. These earliest stars are very rare and they are characteristically low in heavy metals because of their age. They were made of Big Bang material, mostly hydrogen and helium. It was only later that heavier elements were formed in the nuclear furnaces of newer stars.

 In their first study, Preston and Shectman compiled a list

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