Rocks, fossils, and other natural relics hold clues to ancient environments in the form of different ratios of isotopes—atomic variants of elements with the same number of protons but different numbers of neutrons. Seawater, rain water, oxygen, and ozone, for instance, all have different ratios, or fingerprints, of the oxygen isotopes 16O, 17O, and 18O. Weathering, ground water, and direct deposition of atmospheric aerosols change the ratios of the isotopes in a rock revealing a lot about the past climate.

Douglas Rumble’s research is centered on these three stable isotopes of oxygen and the four stable isotopes of sulfur 32S , 33S , 34S, and 36S. In addition to revealing what happened in Earth’s past, he uses oxygen isotopes to distinguish processes that occurred in the solar nebula from those taking place in planetary bodies after their condensation from the nebula.

The four stable sulfur   isotopes also provide insights into the evolution of Earth’s atmosphere in the form of anomalous separations recorded in sulfur-bearing minerals from rocks as old as 3.8 billion years.

To understand Earth's earliest history--its formation from Solar System material into the present-day layering of metal core and mantle, and crust—Rumble and team look to meteorites. Recently they looked at a particularly old type of meteorite called diogenites and examined then using an array of techniques, including precise analysis of certain elements for important clues to some of the Solar System's earliest chemical processing.

Diogenites represent some of the Solar System's oldest existing examples of heat-related chemical processing. The Rumble team examined nine diogenites and confirmed that these samples came from no fewer than two parent bodies and that the crystallization of their minerals occurred about 4.6 billion years ago, only 2 million years after condensation of the oldest solids in the Solar System giving researchers us a better picture of the earliest days of our Solar System.

Rumble received his B.A in geology from Columbia University and his Ph. D. from Harvard University.  He was then a postdoctoral fellow at Carnegie and went on to become an assistant professor at UCLA before joining the scientific staff at Carnegie in 1973. For more see  https://www.gl.ciw.edu/bios/drumble

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Carnegie mineralogist Robert Hazen
May 28, 2021

Washington, DC—Carnegie Mineralogist Robert Hazen—who advanced the concept that Earth’s geology was shaped by the rise and sustenance of life—will be honored with the 2022 International Mineralogical Association’s Medal for Excellence. The prize recognizes “outstanding scientific publication in the field of mineralogical sciences.”

The medal was created to honor a lifetime of achievement in and outstanding contributions to the fields of mineralogy, geochemistry, petrology, crystallography, and applied mineralogy.  Hazen will be its 11th recipient.

A Staff Scientist at Carnegie’s Earth and Planets Laboratory, Hazen

 Photo of inclusions in a super-deep diamond by Evan Smith/© 2021 GIA
May 26, 2021

Washington, DC— The cause of Earth’s deepest earthquakes has been a mystery to science for more than a century, but a team of Carnegie scientists may have cracked the case.

New research published in AGU Advances provides evidence that fluids play a key role in deep-focus earthquakes—which occur between 300 and 700 kilometers below the planet’s surface. The research team includes Carnegie scientists Steven Shirey, Lara Wagner, Peter van Keken, and Michael Walter, as well as the University of Alberta’s Graham Pearson.

Most earthquakes occur close to the Earth’s surface, down to about 70 kilometers.  They happen when stress builds up at

A violent stellar flare erupting on Proxima Centauri. Credit: NRAO/S. Dagnello.
April 21, 2021

Washington, DC— A team of astronomers including Carnegie’s Alycia Weinberger and former-Carnegie postdoc Meredith MacGregor, now an assistant professor at the University of Colorado Boulder, spotted an extreme outburst, or flare, from the Sun’s nearest neighbor—the star Proxima Centauri.

Their work, which could help guide the search for life beyond our Solar System, is published in The Astrophysical Journal Letters.

Proxima Centauri is a “red dwarf” with about one-eighth the mass of our Sun, which sits just four light-years, or almost 25 trillion miles, from the center of our Solar System and hosts at least two planets, one of which may

Lava deposits in Leilani Estates (Credit: B. Shiro, USGS)
April 7, 2021

Washington, DC— The 2018 eruption of Kīlauea Volcano in Hawai‘i provided scientists with an unprecedented opportunity to identify new factors that could help forecast the hazard potential of future eruptions.

The properties of the magma inside a volcano affect how an eruption will play out. In particular, the viscosity of this molten rock is a major factor in influencing how hazardous an eruption could be for nearby communities.

Very viscous magmas are linked with more powerful explosions because they can block gas from escaping through vents, allowing pressure to build up inside the volcano’s plumbing system. On the other hand, extrusion of more viscous

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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.

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

Phillip Cleves’ Ph.D. research was on determining the genetic changes that drive morphological evolution. He used the emerging model organism, the stickleback fish, to map genetic changes that control skeletal evolution. Using new genetic mapping and reverse genetic tools developed during his Ph.D., Cleves identified regulatory changes in a protein called bone morphogenetic protein 6 that were responsible for an evolved increase in tooth number in stickleback. This work illustrated how molecular changes can generate morphological novelty in vertebrates.

Cleves returned to his passion for coral research in his postdoctoral work in John Pringles’ lab at Stanford

Brittany Belin joined the Department of Embryology staff in August 2020. Her Ph.D. research involved developing new tools for in vivo imaging of actin in cell nuclei. Actin is a major structural element in eukaryotic cells—cells with a nucleus and organelles —forming contractile polymers that drive muscle contraction, the migration of immune cells to  infection sites, and the movement of signals from one part of a cell to another. Using the tools developed in her Ph.D., Belin discovered a new role for actin in aiding the repair of DNA breaks in human cells caused by carcinogens, UV light, and other mutagens.

Belin changed course for her postdoctoral work, in

Evolutionary geneticist Moises Exposito-Alonso joined the Department of Plant Biology as a staff associate in September 2019. He investigates whether and how plants will evolve to keep pace with climate change by conducting large-scale ecological and genome sequencing experiments. He also develops computational methods to derive fundamental principles of evolution, such as how fast natural populations acquire new mutations and how past climates shaped continental-scale biodiversity patterns. His goal is to use these first principles and computational approaches to forecast evolutionary outcomes of populations under climate change to anticipate potential future