Astronomy Stories
Pasadena, CA— New work from a team of astronomers led by Carnegie’s Jennifer van Saders indicates that one recently developed method for determining a star’s age needs to be...
Explore this Story
This video was part of the 2015 Open House at the Carnegie Observatories in Pasadena, CA,. We show plates from 1894 to 1971, how they were made at Mount Wilson and Palomar Observatories, and it...
Explore this Story
Pasadena, CA – November 11, 2015 – Leading scientists, senior officials, and supporters from an international consortium of universities and research institutions are gathering on a...
Explore this Story
Scientists, including researchers from the Carnegie Institution for Science, discuss the search for extrasolar planets. This video is provided courtesy of NASA.
Explore this Story
Yuri Beletsky's recent image of  the lunar eclipse at  Carnegie's Las Campanas Observatory has been published by NASA as the Astronomy Picture of the Day, October 1, 2015. The...
Explore this Story
Popular Mechanics: Clyde Tombaugh still discovered the dwarf planet, but this is the latest "precovery" image to be unearthed....
Explore this Story
Pasadena, CA— Astronomer and instrumentation expert Stephen Shectman of the Carnegie Observatories has been selected to receive the Maria and Eric Muhlmann Award from the Astronomical Society...
Explore this Story


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 recent discovery that the universe is expanding at an accelerating rate has profoundly affected physics. If the universe were gravity-dominated then it should be decelerating. These contrary results suggest a new form of “dark energy”—some kind of repulsive force—is...
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
Galacticus is not a super hero; it’s a super model used to determine the formation and evolution of the galaxies. Developed by Andrew Benson, the George Ellery Hale Distinguished Scholar in Theoretical Astrophysics, it is one of the most advanced models of galaxy formation available. Rather...
Meet this Scientist
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...
Meet this Scientist
Alycia Weinberger wants to understand how planets form, so she observes young stars in our galaxy and their disks, from which planets are born. She also looks for and studies planetary systems. Studying disks surrounding nearby stars help us determine the necessary conditions for planet formation....
Meet this Scientist
You May Also Like...
Pasadena, CA—An international team of astronomers, including Carnegie’s Eric Persson, has charted the rise and fall of galaxies over 90 percent of cosmic history. Their work, which includes some of...
Explore this Story
Washington, D.C.--Scientists with the Giant Magellan Telescope Organization have completed the most challenging large astronomical mirror ever made. The mirror will be part of the 25-meter Giant...
Explore this Story
A team of astronomers, including Carnegie’s Benjamin Shappee, Nidia Morrell, and Ian Thompson, has discovered the most-luminous supernova ever observed, called ASAS-SN-15lh. It is two...
Explore this Story

Explore Carnegie Science

Earth's Moon, public domain image
January 23, 2019

Pasadena, CA— “Can moons have moons?”

This simple question—asked by the four-year old son of Carnegie’s Juna Kollmeier—started it all.  Not long after this initial bedtime query,  Kollmeier was coordinating a program at the Kavli Institute for Theoretical Physics (KITP)  on the Milky Way while her one-time college classmate Sean Raymond of Université de Bordeaux was attending a parallel KITP program on the dynamics of Earth-like planets.   After discussing this very simple question at a seminar, the two joined forces to solve it.  Their findings are the basis of a paper published in Monthly Notices

December 14, 2018

Pasadena, CA— Miguel Roth, director of Carnegie’s Las Campanas Observatory in Chile from 1990 to 2014 and the current representative of the Giant Magellan Telescope Organization (GMTO) in Chile was awarded the Bernardo O’Higgins Order by the Chilean Foreign Affairs Ministry in Santiago today. The honor is in recognition “of his contribution to the development of astronomy in Chile, and for inspiring appreciation and knowledge of astronomy among students and people of all ages.”

The award is the highest civilian honor for non-Chileans. O’Higgins was one of the founders of the Chilean Republic. The award was established in 1965 to recognize

An artist’s conception of a type Ia supernova exploding, courtesy of ESO.
December 11, 2018

Pasadena, CA—New work from the Carnegie Supernova Project provides the best-yet calibrations for using type Ia supernovae to measure cosmic distances, which has implications for our understanding of how fast the universe is expanding and the role dark energy may play in driving this process. Led by Carnegie astronomer Chris Burns, the team’s findings are published in The Astrophysical Journal.  

Type Ia supernovae are fantastically bright stellar phenomena. They are violent explosions of a white dwarf—the crystalline remnant of a star that has exhausted its nuclear fuel—which is part of a binary system with another star.

In addition to being

Pan-STARRS image showing the host galaxy of the newly discovered supernova ASASSN-18bt
November 29, 2018

Pasadena, CA—A supernova discovered by an international group of astronomers including Carnegie’s Tom Holoien and Maria Drout, and led by University of Hawaii’s Ben Shappee, provides an unprecedented look at the first moments of a violent stellar explosion. The light from the explosion's first hours showed an unexpected pattern, which Carnegie's Anthony Piro analyzed to reveal that the genesis of these phenomena is even more mysterious than previously thought.

Their findings are published in a trio of papers in The Astrophysical Journal and The Astrophysical Journal Letters. (You can read them here, here, and here.)

Type Ia supernovae are

No content in this section.

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

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-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

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

Galacticus is not a super hero; it’s a super model used to determine the formation and evolution of the galaxies. Developed by Andrew Benson, the George Ellery Hale Distinguished Scholar in Theoretical Astrophysics, it is one of the most advanced models of galaxy formation available.

Rather than building his model around observational data, Benson’s Galacticus relies on known laws of physics and the so-called N-body problem, which predicts the motions of celestial bodies that interact gravitationally in groups. Galacticus’ now an open- source model produces results as stunning 3-D videos.

Some 80% of the matter in the universe cannot be seen. This unseen

Anthony Piro is the George Ellery Hale Distinguished Scholar in Theoretical Astrophysics at the Carnegie Observatories. He is a theoretical astrophysicist studying compact objects, astrophysical explosions, accretion flows, and stellar dynamics. His expertise is in nuclear physics, thermodynamics, condensed matter physics, General Relativity, and fluid and magneto-hydrodanmics. He uses this background  to predict new observational phenomena as well as to understand the key underlying physical mechanisms responsible for current observations. He uses a combination of analytic and simple numerical models to build physical intuition for complex phenomena.

Piro recieved his 

Staff member emeritus François Schweizer studies galaxy assembly and evolution by observing nearby galaxies, particularly how collisions and mergers affect their properties. His research has added to the awareness that these events are dominant processes in shaping galaxies and determining their stellar and gaseous contents.

When nearby galaxies collide and merge they yield valuable clues about processes that occurred much more frequently in the younger, distant universe. When two gas-rich galaxies collide, their pervasive interstellar gas gets compressed, clumps into dense clouds, and fuels the sudden birth of billions of new stars and thousands of star clusters.

Looking far into space is looking back in time. Staff astronomer emeritus Alan Dressler began his career at Carnegie some years ago as a Carnegie Fellow. Today, he and colleagues use Magellan and the Hubble Space Telescope to study galaxy evolution—how galaxy structures and shapes change, the pace and character of star birth, and how large galaxies form from earlier, smaller systems.

Dressler is also intricately involved in instrumentation. He led the effort for the Inamori Magellan Areal Spectrogrph (IMACS), a wide-field imager and multi-object spectrograph which became operational in 2003 on the Baade telescope at Carnegie’s Las Campanas Observatory. Spectrographs