Anat Shahar is pioneering a field that blends isotope geochemistry with high-pressure experiments to examine planetary cores and the Solar System’s formation, prior to planet formation, and how the planets formed and differentiated. Stable isotope geochemistry is the study of how physical and chemical processes can cause isotopes—atoms of an element with different numbers of neutrons-- to separate (called isotopic fractionation). Experimental petrology is a lab-based approach to increasing the pressure and temperature of materials to simulate conditions in the interior Earth or other planetary bodies.

Rocks and meteorites consist of isotopes that contain chemical fingerprints of long-gone eras. The lighter isotopes, with fewer neutrons, partially separate from heavier isotopes (fractionation). The different ratios of these isotopes can reveal the physical and chemical changes these materials have undergone.

Comparing seismic measurements and information on materials, researchers know that Earth’s outer core is not pure iron and nickel; something lighter is there. One candidate is silicon, the most abundant element in the crust. Shahar and her colleagues developed a way to test the silicon hypothesis. They developed lab techniques to define how isotopes of silicon and iron separate between metals characteristic of the core and silicate of the mantle under Earth-forming high pressures and temperatures. The results were compared with isotopes found in rocks on Earth and the most primitive meteorites called chondrites. Chondrites contain tiny grains of dust from the period when the Solar System began to coalesce. They found that the core could contain as much as 6% silicon by weight.   

Shahar received her B.S. and M. Eng. from Cornell University in geological engineering and geological sciences respectively. She received her Ph. D. in geochemistry from UCLA. Before becoming a staff scientist in 2009 she was a Carnegie postdoctoral fellow. For more see http://anatshahar.carnegiescience.edu

 

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Carnegie Earth and Planets Laboratory isotope geochemist Anat Shahar
September 10, 2021

Washington, DC—Carnegie geochemist Anat Shahar, who probes the formation, evolution, and interior dynamics of Earth and other rocky planets, has been selected to give the Reginald Daly Lecture at the American Geophysical Union’s annual Fall Meeting in December.  

In honor of its namesake’s contributions to understanding the forces that shaped our planet, recipients for this recognition are selected for exemplifying excellence in the geosciences.

Earth and Planets Laboratory Staff Scientist Anat Shahar, also the institution’s Associate Science Deputy, uses a combination of isotope geochemistry and high-pressure, high-temperature experiments to

Diana Roman collecting samples, courtesy of Anna Barth, LDEO.
September 1, 2021

Washington, DC—Our planet provides ample research opportunities for scientists like Diana Roman, who has devoted her career to understanding the geologic forces that shape volcanic eruptions. She just needs to be on standby to seize them when they arrive.

Roman, recently named a Harry Oscar Wood Chair of Seismology at the Carnegie Institution for Science, wasn’t initially planning to travel to Iceland to get a look at the Fagradalsfjall “baby” volcano—in Geldingadalir—which erupted onto the scene in the Reykjanes Peninsula just this past March, mesmerizing the world with images of its cascading lava and “science fair”-style cone.

Lara Wagner and Diana Roman the inaugural Harry Oscar Wood Chairs of Seismology
August 30, 2021

Washington, DC—Carnegie has named Earth and Planets Laboratory Staff Scientists Diana Roman and Lara Wagner as the inaugural Harry Oscar Wood Chairs of Seismology. 

Roman's work straddles the boundary between volcanology and seismology. Her primary research efforts focus on the mechanics of how magma moves through the Earth’s crust, and on the structure, evolution, and dynamics of volcanic systems. 

Wagner uses seismology to understand the formation and evolution of Earth’s continental crust, which records billions of years of plate tectonic activity. She uses seismic waves generated by earthquakes to probe the structures of our planet’

Asteroid 2021 PH27 courtesy Katherine Cain/ Carnegie Institution for Science.
August 23, 2021

Washington, DC—The Sun has a new neighbor that was hiding in plain twilight. An asteroid that orbits the Sun in just 113 days—the shortest known orbital period for an asteroid and second shortest for any object in our Solar System after Mercury—was discovered by Carnegie’s Scott S. Sheppard in evening twilight images taken by Brown University’s Ian Dell'Antonio and Shenming Fu.

The newfound asteroid, called 2021 PH27, is about 1 kilometer in size and is on an unstable orbit that crosses that of Mercury and Venus. This means that within a few million years it will likely be destroyed in a collision with one of these planets or the Sun, or it will

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Established in June of 2016 with a generous gift of $50,000 from Marilyn Fogel and Christopher Swarth, the Marilyn Fogel Endowed Fund for Internships will provide support for “very young budding scientists” who wish to “spend a summer getting their feet wet in research for the very first time.”  The income from this endowed fund will enable high school students and undergraduates to conduct mentored internships at Carnegie’s Geophysical Laboratory and Department of Terrestrial Magnetism in Washington, DC starting in the summer of 2017.

Marilyn Fogel’s thirty-three year career at Carnegie’s Geophysical Laboratory (1977-2013), followed

CALL FOR PROPOSALS

Following Andrew Carnegie’s founding encouragement of liberal discovery-driven research, the Carnegie Institution for Science offers its scientists a new resource for pursuing bold ideas.

Carnegie Science Venture grants are internal awards of up to $100,000 that are intended to foster entirely new directions of research by teams of scientists that ignore departmental boundaries. Up to six adventurous investigations may be funded each year. The period of the award is two

Andrew Steele joins the Rosetta team as a co-investigator working on the COSAC instrument aboard the Philae lander (Fred Goesmann Max Planck Institute - PI). On 12 November 2014 the Philae system will be deployed to land on the comet and begin operations. Before this, several analyses of the comet environment are scheduled from an approximate orbit of 10 km from the comet. The COSAC instrument is a Gas Chromatograph Mass Spectrometer that will measure the abundance of volatile gases and organic carbon compounds in the coma and solid samples of the comet.

The Anglo-Australian Planet Search (AAPS) is a long-term program being carried out on the 3.9-meter Anglo-Australian Telescope (AAT) to search for giant planets around more than 240 nearby Sun-like stars. The team, including Carnegie scientists,  uses the "Doppler wobble" technique to search for these otherwise invisible extra-solar planets, and achieve the highest long-term precision demonstrated by any Southern Hemisphere planet search.

Ana Bonaca is Staff Member at Carnegie Observatories. Her specialty is stellar dynamics and her research aims to uncover the structure and evolution of our galaxy, the Milky Way, especially the dark matter halo that surrounds it. In her research, she uses space- and ground-based telescopes to measure the motions of stars, and constructs numerical experiments to discover how dark matter affected them.

She arrived in September 2021 from Harvard University where she held a prestigious Institute for Theory and Computation Fellowship. 

Bonaca studies how the uneven pull of our galaxy’s gravity affects objects called globular clusters—spheres made up of a million

Peter Gao's research interests include planetary atmospheres; exoplanet characterization; planet formation and evolution; atmosphere-surface-interior interactions; astrobiology; habitability; biosignatures; numerical modeling.

His arrival in September 2021 continued Carnegie's longstanding tradition excellence in exoplanet discovery and research, which is crucial as the field prepares for an onslaught of new data about exoplanetary atmospheres when the next generation of telescopes come online.

Gao has been a part of several exploratory teams that investigated sulfuric acid clouds on Venus, methane on Mars, and the atmospheric hazes of Pluto. He also

Anne Pommier's research is dedicated to understanding how terrestrial planets work, especially the role of silicate and metallic melts in planetary interiors, from the scale of volcanic magma reservoirs to core-scale and planetary-scale processes.

She joined Carnegie in July 2021 from U.C. San Diego’s Scripps Institution of Oceanography, where she investigated the evolution and structure of planetary interiors, including our own Earth and its Moon, as well as Mars, Mercury, and the moon Ganymede.

Pommier’s experimental petrology and mineral physics work are an excellent addition to Carnegie’s longstanding leadership in lab-based mimicry of the

Johanna Teske became the first new staff member to join Carnegie’s newly named Earth and Planets Laboratory (EPL) in Washington, D.C., on September 1, 2020. She has been a NASA Hubble Fellow at the Carnegie Observatories in Pasadena, CA, since 2018. From 2014 to 2017 she was the Carnegie Origins Postdoctoral Fellow—a joint position between Carnegie’s Department of Terrestrial Magnetism (now part of EPL) and the Carnegie Observatories.

Teske is interested in the diversity in exoplanet compositions and the origins of that diversity. She uses observations to estimate exoplanet interior and atmospheric compositions, and the chemical environments of their formation