Mark Phillips is the Las Campanas Observatory (LCO) Director Emeritus. From 2006 to 2017 Phillips served as the Associate Director for Magellan, and from 2014 to 2017 he was the interim LCO Director. He is a world-renowned supernova expert. Most stars die quietly by cooling down and “turning off” when they have exhausted their nuclear fuel. But, a few stars end in a gigantic thermonuclear explosion known as a supernova. These objects remain extremely bright for a few weeks, sometimes outshining the galaxies in which they reside. Their extreme brightness at maximum makes them potentially powerful “standard candles”—baselines for probing distances, geometry, and expansion of the universe.

Type Ia supernovae are especially attractive. Thought to be the complete thermonuclear disruption of a small, very dense stellar remnant called a white dwarf, they are highly uniform. And because of their immense luminosity at maximum light (up to 10 billion times that of the Sun), they can be observed at great distances. Phillips wants to understand the role they have in the evolution of the universe, and to determine how they can be used as standard candles for measuring distance.

Phillips has shown that Type Ia supernovae can be used as standard candles because of a tight correlation between the rate of decline from maximum light and peak luminosity. Phillips and collaborators have extended their supernovae observations to the infrared and found that Type Ia supernovae exhibit a much smaller range of luminosities at these wavelengths, making them nearly perfect standard candles. Particularly important is that in infrared the absorption of the supernova light due to dust is negligible.

Phillip joined a two-part, 5-year project called the Carnegie Supernova Program (CSP). The team is obtaining light curves—how light varies over time—of some 100 nearby Type Ia supernovae in the optical and infrared. This sample will provide a comparison for the second component of the project—near-infrared observations of about 50 very distant—known as high-redshift (0.3 < z < 0.7) —Type Ia supernovae. The goal is to measure the expansion history of the universe at different distances for a new measurement of the acceleration of the universe, which should provide clues to the nature of the mysterious dark energy that is driving the acceleration.

Phillips received an A.B. from San Diego State University and a Ph.D. in astronomy from UC-Santa Cruz. After graduate school, he was a postdoctoral associate at both Cerro Tololo Inter-American Observatory (CTIO), and the Anglo-Australian Observatory. He then moved back to Chile in 1982 to become a staff astronomer at CTIO. He was later director of the CTIO  National Optical Astronomy Observatory, before joining Carnegie  in 1998.  For more see http://obs.carnegiescience.edu/users/mmp

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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

December 6, 2017

Pasadena, CA— A team of astronomers led by Carnegie’s Eduardo Bañados used Carnegie’s Magellan telescopes to discover the most-distant supermassive black hole ever observed. It resides in a luminous quasar and its light reaches us from when the universe was only 5 percent of its current age—just 690 million years after the Big Bang. Their findings are published by Nature.

Quasars are tremendously bright objects comprised of enormous black holes accreting matter at the centers of massive galaxies. This newly discovered black hole has a mass that is 800 million times the mass of our Sun.

“Gathering all this mass in fewer than 690 million years is an enormous challenge for

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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.

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.

Peter Driscoll studies the evolution of Earth’s core and magnetic field including magnetic pole reversal. Over the last 20 million or so years, the north and south magnetic poles on Earth have reversed about every 200,000, to 300,000 years and is now long overdue. He also investigates the Earth’s inner core structure; core-mantle coupling; tectonic-volatile cycling; orbital migration—how Earth’s orbit moves—and tidal dissipation—the dissipation of tidal forces between two closely orbiting bodies. He is also interested in planetary interiors, dynamos, upper planetary atmospheres and exoplanets—planets orbiting other stars. He uses large-scale numerical simulations in much of his research