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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Artist's conception. Credit Rensselaer Polytechnic Institute
February 14, 2019

Washington, DC—Carnegie’s Andrew Steele is a member of the Earth First Origins project, led by Rensselaer Polytechnic Institute’s Karyn Rogers, which has been awarded a $9 million grant by NASA’s Astrobiology Program.

The five-year project seeks to uncover the conditions on early Earth that gave rise to life by identifying, replicating, and exploring how prebiotic molecules and chemical pathways could have formed under realistic early Earth conditions.

The evolution of planet Earth and the emergence of life during its first half-billion years are inextricably linked, with a series of planetwide transformations – formation of the ocean,

Self-portrait of NASA's Curiosity Mars rover on Vera Rubin Ridge with Mount Sharp poking up just behind the vehicle's mast. Image is courtesy of NASA/JPL-Caltech/MSSS Curiosity.
January 31, 2019

Washington, DC—The density of rock layers on the terrain that climbs from the base of Mars’ Gale Crater to Mount Sharp is less dense than expected, according to the latest report on the Red Planet’s geology from a team of scientists including Carnegie’s Shaunna Morrison. Their work is published in Science.

Scientists still aren't sure how this mountain grew inside of the crater, which has been a longstanding mystery. 

One idea is that sediment once filled Gale Crater and was then worn away by millions of years of wind and erosion, excavating the mountain. However, if the crater had been filled to the brim, the material on the bottom, which

Artist concept of 2018 VG18, nicknamed "Farout.” Illustration by Roberto Molar Candanosa is courtesy of the Carnegie Institution for Science.
December 17, 2018

Washington, DC— A team of astronomers has discovered the most-distant body ever observed in our Solar System.  It is the first known Solar System object that has been detected at a distance that is more than 100 times farther than Earth is from the Sun.

The new object was announced on Monday, December 17, 2018, by the International Astronomical Union’s Minor Planet Center and has been given the provisional designation 2018 VG18. The discovery was made by Carnegie’s Scott S. Sheppard, the University of Hawaii’s David Tholen, and Northern Arizona University’s Chad Trujillo.

2018 VG18, nicknamed “Farout” by the discovery team for

Artist’s impression of Barnard’s Star planet under the orange tinted light from the star.  Credit: IEEC/Science-Wave - Guillem Ramisa
November 14, 2018

Washington, DC—An international team including five Carnegie astronomers has discovered a frozen Super-Earth orbiting Barnard’s star, the closest single star to our own Sun. The Planet Finder Spectrograph on Carnegie’s Magellan II telescope was integral to the discovery, which is published in Nature.

Just six light-years from Earth, Barnard’s star is our fourth-closest neighboring star overall, after Alpha Centauri’s triple-star system. It is smaller and older than our Sun and among the least-active known red dwarfs.

To find this cold Super-Earth, the team—which included Carnegie’s Paul Butler, Johanna Teske, Jeff Crane, Steve

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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.

Carbon plays an unparalleled role in our lives: as the element of life, as the basis of most of society’s energy, as the backbone of most new materials, and as the central focus in efforts to understand Earth’s variable and uncertain climate. Yet in spite of carbon’s importance, scientists remain largely ignorant of the physical, chemical, and biological behavior of many of Earth’s carbon-bearing systems. The Deep Carbon Observatory (DCO) is a global research program to transform our understanding of carbon in Earth. At its heart, DCO is a community of scientists, from biologists to physicists, geoscientists to chemists, and many others whose work crosses these

Staff Associate Kamena Kostova joined the Department of Embryology in November 2018. She studies ribosomes, the factory-like structures inside cells that produce proteins. Scientists have known about ribosome structure, function, and biogenesis for some time. But, a major unanswered question is how cells monitor the integrity of the ribosome itself. Problems with ribosomes have been associated with diseases including neurodegeneration and cancer. The Kostova lab investigates the fundamental question of how cells respond when their ribosomes break down using mass spectrometry, functional genomics methods, and CRISPR genome editing.

Kostova received a B.S. in Biology from the

Sally June Tracy applies cutting-edge experimental and analytical techniques to understand the fundamental physical behavior of materials at extreme conditions. She uses dynamic compression techniques with high-flux X-ray sources to probe the structural changes and phase transitions in materials at conditions that mimic impacts and the interiors of terrestrial and exoplanets. She is also an expert in nuclear resonant scattering and synchrotron X-ray diffraction. She uses these techniques to understand novel behavior at the electronic level.  Tracy received her Ph.D. from the California Institute of

The Ludington lab investigates complex ecological dynamics from microbial community interactions using the fruit fly  Drosophila melanogaster. The fruit fly gut carries numerous microbial species, which can be cultured in the lab. The goal is to understand the gut ecology and how it relates to host health, among other questions, by taking advantage of the fast time-scale and ease of studying the fruit fly in controlled experiments. 

Nick Konidaris is a staff scientist at the Carnegie Observatories and Instrument Lead for the SDSS-V Local Volume Mapper (LVM). He works on a broad range of new optical instrumentation projects in astronomy and remote sensing. Nick's projects range from experimental to large workhorse facilities. On the experimental side, he recently began working on a new development platform for the 40-inch Swope telescope at Carnegie's Las Campanas Observatory that will be used to explore and understand the explosive universe.

 Nick and his colleagues at the Department of Global Ecology are leveraging the work on Swope to develop a new airborne spectrograph that will be