The Broad Branch Road Neighborhood Lectures provide an opportunity to get up close and personal with Carnegie scientists at our campus in northwest Washington DC. These lectures begin at 6:30 p.m. and last for approximately one hour, followed by a brief question and answer period. Doors open to the public at 6:00 p.m. with light refreshments. The campus is located at the intersection of Broad Branch Road and 32nd Street in northwest Washington, DC.Parking is available on campus and accessible via Jocelyn and 32nd Streets. Street parking is permissible.
The campus is a short, three-block walk from Connecticut Avenue and two blocks south of Military Road. For directions, click here.
Registration is strongly recommended.

Dr. Paul Butler - Alien Worlds and the Origins of Science

Thursday, May 14, 2015 - 6:30pm to 7:30pm

Modern science began with Copernicus speculating that the Earth is a planet and that all the planets orbit the Sun. Bruno followed up by speculating that the Sun is a star, that other stars have planets, and other planets are inhabited by life. For this and other heresies, Bruno was burned at the stake in a public square in Rome in 1600. Astronomy and extrasolar planets were a really hot field at the time.

Over the past 20 years more than a thousand extrasolar planets have been found, first from ground-based precision Doppler surveys, and more recently by the Kepler space mission. We have concentrated on building precise Doppler systems to survey the nearest stars. Our systems at Lick, Keck, AAT, and Magellan have found hundreds of planets, including five of the first six extrasolar planets, the first saturn-mass planet, the first neptune-mass planet, the first terrestrial mass planet, and the first multiple planet systems.

We are focused on surveying the nearest stars with new custom built spectrometers designed to achieve the highest possible Doppler precision: The Planet Finder Spectrometer on the 6.5-m Magellan Telescope, and the Levy spectrometer on the 2.4-m Automated Planet Finding Telescope. These spectrometer will lead to the discovery of many terrestrial mass and potentially habitable planets over the next decade. Within a generation new technology giant telescopes and adaptive optics systems will be able to directly image these systems and begin the detailed search for life.

View Streaming Video.

From Outpost to Icon: A Century of Science at Broad Branch Road

Thursday, September 24, 2015 - 7:00pm to 8:00pm

How did a leafy tract on the rural fringe of Washington a century ago become home to a world-class think tank for scientific research? Join us for an evening of history and science as Carnegie librarian Shaun Hardy recounts the fascinating story of the Broad Branch Road campus – from its inception in 1914 as a “mission control center” for magnetic survey expeditions and sailing ships that crisscrossed the globe to its present role as an interdisciplinary research center for the Earth and planetary sciences.

Using historic photos from Carnegie’s archives we’ll explore the atom-smashers, radio telescopes, and other cutting-edge facilities erected “on the hill” over the past 100 years. We’ll also highlight some of the most significant breakthroughs by DTM and Geophysical Laboratory scientists, including the discovery of dark matter in the universe and top-secret research that helped shorten World War II. 


Memoirs of a Mineral

Thursday, October 15, 2015 - 6:30pm to 7:30pm

Minerals record information that is vital to our understanding of Earth’s formation and evolution. Join me as I take you on a journey to explore a group of minerals that form from magmas. Hidden within these minerals are records of magmatic events that lead to volcanic eruptions and are recorded in the form of chemical and isotopic profiles. Discover how these profiles can be used to visualize the transport of magma inside a volcano.

Viktor Struzhkin - The Quest for Room Temperature Superconductivity

Thursday, April 16, 2015 - 6:30pm to 7:30pm

Superconductivity is a rare physical state in which matter is able to conduct electricity without any resistance. It can only be found in certain materials, and even then it can only be achieved under specific temperature and pressure conditions. Although superconductivity has many practical applications for electronics, medical engineering, power transmission and storage, the difficulty of creating superconducting materials prevents it from being used to its full potential. Traditionally superconductors were made only in extremely low temperatures. But over time scientists discovered that applying pressure could create superconductors at somewhat higher temperatures. Here at the Geophysical Lab, we have developed very sensitive techniques capable of creating and detecting superconductivity under very high pressures. Viktor Struzhkin will detail our efforts in finding higher-temperature superconductivity.

Water in the Moon’s Interior: Truth and Consequences

Thursday, November 5, 2015 - 6:30pm to 7:30pm

The Moon has been an object of mystery, curiosity, wonder, observation, fascination and speculation since the dawn of mankind. It has inspired fear and worship, medieval and renaissance art, the modern calendar, hundreds of pieces of music, a race to space that consumed nearly 5% of the US budget at its height, conspiracy theories, a rock album that spent more than 14 years on the Billboard Top 100 charts, one good movie (2001: A Space Odyssey) and several bad ones.
Scientifically, the Moon is no less interesting. The Apollo program returned a literal treasure trove of samples totaling nearly 840 pounds. We have learned that the Moon formed from the debris ejected from an ancient giant impact of a planetary embryo with the Earth, and that it was covered in an ocean of magma that froze and produced “rockbergs” that make up the light-colored lunar highlands that we see today.
The Moon is too small to retain an atmosphere, and so any water that may have once been at the Moon’s surface has either remained frozen in polar craters or has evaporated into space. Yet new studies at Carnegie on lunar volcanic rocks, erupted more than three billion years ago, have determined that the Moon’s interior may have nearly as much water as the Earth’s interior. This represents a surprising discovery – another mystery - about an object that was once molten in the vacuum of space.

Dr. Alexander Goncharov - High-Pressure Alchemy

Thursday, April 28, 2016 - 6:30pm to 7:30pm


A major focus of the field of chemistry is predicting how various atoms form bonds, hence molecules, and how such bonding controls the structure and properties of molecular matter. Historically, almost all chemistry has been performed at ambient pressure - the atmospheric pressure at the Earth’s surface. However, the majority of matter in the universe resides at extreme pressures and temperatures that force atoms into extremely close contact, where chemical behavior can become surprising, and where very exotic compounds can become stable.
During this lecture, Dr. Goncharov will explain how we do experiments at extreme pressures, in some cases exceeding one million atmospheres. He will present some recent discoveries of unusual “salts,” and stable compounds with noble gases. These exotic materials hold a promise of potentially unparalleled physical and chemical properties. Many of these newly discovered extreme materials are made of the most abundant elements in the universe and thus are likely to be present in the interiors of giant planets such as Jupiter and Saturn. 

Dr. Alexander Goncharov
Staff Scientist, Geophysical Laboratory
Carnegie Institution for Science

Scott Sheppard - Beyond Pluto: The Hunt for Planet X

Thursday, May 19, 2016 - 6:30pm to 7:30pm

The Kuiper Belt, which has Pluto as the largest member, is a region of comet-like objects just beyond Neptune. This belt of objects has an outer edge, which we are only now able to explore in detail. For the past few years we have been performing the largest and deepest survey ever attempted to search for distant solar system objects. The ongoing search has discovered the object with the most distant orbit known in our solar system and several of the largest known objects after the major planets.
These extremely distant objects are strangely grouped closely together in space, which suggests a yet unobserved planet more massive than the Earth is shepherding them into these similar orbits. Dr. Sheppard will discuss the most recent discoveries at the fringe of our solar system.

Dr. Scott Sheppard
Staff Scientist, Department of Terrestrial Magnetism
Carnegie Institution for Science

Dr. Lara Wagner - Pointing the Telescope Down: Seismo-vision into the Earth’s Interior

Thursday, October 20, 2016 - 6:30pm to 7:30pm

Please note that tickets are not required and seating is first come, first serve. Tickets from Eventbrite enable you to skip the sign-in process at the door, but do not guarantee a seat. 

Astronomers use large and increasingly more intricate telescopes to see further and further into the cosmos with ever-improving resolution.  These instruments have lead to the discovery of other planets around distant stars, some of which might be capable of supporting life.  But the key to life’s evolution on Earth is the development and persistence of plate tectonics, a planetary process that affects everything from the mineral composition of the continents on which we stand to the existence of liquid water on Earth’s surface.  To study the inner workings of our world, we need to look down, deep into the Earth’s interior to see how plate tectonics moves materials into and out of the planet, preferentially keeping some materials at the surface while recycling others deep into the lower mantle.  

Seismology allows us to “see” inside the Earth much like a CAT scan allows a doctor to see the insides of a human body.  Instead of light waves or X-rays, seismologists use seismic waves to take “snapshots” of the planet’s interior structure.  By studying these snapshots, we can learn a great deal about both the ancient tectonic history responsible for creating these internal structures, and the ongoing plate tectonic processes that sustain life while also producing some of the world’s most devastating natural disasters.  Key to answering many of these questions is figuring out how water and other volatiles move into and back out of the Earth.  It is a difficult question to answer because the structures that carry these fluids are small, and the depths to which we want to observe them are great.

Much like telescopes, the ability of seismometers to image the planet’s interior depends on the density of the seismic sensors (how close they are to each other) and the “aperture” of the array (how big of an area the sensors cover).  More density means higher resolution.  Bigger aperture means greater depths of focus.  This talk will show some recent examples of each of these types of studies (high density/ broad aperture), and will give a look at the science potential for the newest generation of seismic equipment that will allow us to pursue both simultaneously.  As we continue to sharpen our image of the deep Earth’s interior, we will better understand what makes our planet special, and what we might expect from planets we find elsewhere in the cosmos.

Dr. Lara Wagner, Department of Terrestrial Magnetism, Carnegie Institution for Science



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Dr. Robert Hazen - The Private Lives of Minerals: Social Network Analysis Applied to Mineralogy

Tuesday, November 15, 2016 - 6:30pm to 7:30pm

Please note that tickets are not required and seating is first come, first serve. Tickets from Eventbrite enable you to skip the sign-in process at the  door,  but do not guarantee a seat. 

The distribution of minerals on Earth, Mars, and other worlds mimics social networks, as commonly applied to such varied topics as Facebook interactions, the spread of disease, and terrorism networks. Applying social network analysis (SNA) to common rocks, such as granite and basalt, reveals patterns of cohesion, segregation, density, and cliques that are similar to those of human social networks. These patterns provide new insights into the way planets evolve, especially the co-evolving geosphere and biosphere. SNA also offers promising new pedagogical approaches to teaching mineralogy and petrology.

Dr. Robert Hazen, Geophysical Laboratory, Carnegie Institution for Science


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Dr. Matthew Scott - Jumping Genes: What They Mean for Evolution and Medicine

Thursday, March 16, 2017 - 6:30pm to 7:30pm

The DNA of one human cell—two copies of our “genome”—would stretch almost two meters if fully extended. However, normally it’s tightly packaged in 46 chromosomes. About 20,000 genes are distributed along this DNA; they carry the information for building and operating a human. Any particular gene is located at a specific place in a chromosome and, normally, stays there. Carnegie scientist Barbara McClintock discovered, in corn, that some genes jump from one place in a chromosome to another. Similar things occur in most organisms, including us. This discovery, which earned a Nobel prize, led to dramatic advances in understanding infectious disease, evolution, and the controls that turn genes on and off in specific places and tissues. This talk will discuss early life on Earth, how jumping genes may have influenced it, and why we should care about jumping genes now … for example if you use antibiotics. 

Dr. Matthew Scott, President, Carnegie Science                                                                                                                                       #JumpingGenes


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Dr. Conel Alexander - Rocks from Space: Be Grateful and a Little Afraid

Thursday, April 27, 2017 - 6:30pm to 7:30pm

‘Rocks’ from space have had a profound influence on the evolution of Earth – from the giant impact that created the Moon, to the asteroids that killed off the dinosaurs and, more locally, created the Chesapeake Bay, to tiny grains that may have brought prebiotic molecules that helped kick start life on Earth. The rate at which the Earth has accreted material from space has decayed dramatically since it formed. Nevertheless, ignoring the occasional large ‘hiccup’, some 30-40 thousand tons of extraterrestrial material fall to Earth every year as meteorites and cosmic dust. This has been a boon to science, providing samples of other stars and Mars, helping to develop our picture of the timescales and conditions at the birth of our Solar System, and providing constraints for how the terrestrial planets formed. In this talk, Alexander will review where and how meteorites and cosmic dust are collected, and what they have taught us about the origin and early evolution of our Solar System. 

Dr. Conel Alexander, Deparment of Terrestrial Magnetism, Carnegie Science                                           #SpaceRocks

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Dr. Andrew Steele - Mars, Moons, Missions & Microbes: Life as We Don’t Know It - How Do We Find It?

Thursday, May 25, 2017 - 6:30pm to 7:30pm

The main focus behind Steele’s research has been the development of scientific and measurement criteria for the unambiguous detection of life in early Earth and Mars samples, and future robotic and sample return missions to Mars, Europa, and Enceladus. Steele’s talk will explain how this research has evolved into a three-pronged approach of laboratory investigations using a diverse range of techniques and samples coupled with development and testing of instrumentation for future Mars missions and the characterization of data from space flight missions to Earth orbit, Mars, and comets. 

Dr. Andrew Steele, Geophysical Laboratory, Carnegie Science                                                                             #FindingLife

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Dr. John E. Chambers - The Mystery of Planet Formation

Carnegie Science, Carnegie Institution, Carnegie Institution for Science,
Thursday, October 26, 2017 - 6:30pm to 7:45pm

We all live on a planet, and planets represent the best places to look for life elsewhere in the universe. This makes planets uniquely interesting objects, both for astronomers, and for everyone who is interested in our origins and our place in the cosmos. The Sun’s planets are a diverse bunch, with a wide variety of orbits, sizes, compositions, atmospheres, and climates. Newly discovered planets orbiting other stars are even more varied, and many of these planetary systems are very different than our own. How did this diversity arise? In this lecture, we will explore how planets form and why they look the way they do. We will see how scientists have pieced together the story so far, and what puzzles remain to be solved in the years to come.

Dr. John E. Chambers, Carnegie Department of Terrestrial Magnetism

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Dr. Stephen M. Elardo - The Roadside Geology of Earth’s Moon

Carnegie Science, Carnegie Institution, Carnegie Institution for Science,
Thursday, November 16, 2017 - 6:30pm to 7:45pm

If you enjoyed this summer’s spectacular total solar eclipse, you have the Moon to thank for it! But Earth’s only natural satellite and closest cosmic neighbor does a lot more than occasionally block out the Sun in dramatic fashion. It controls ocean tides, gives us stable seasons and climates, and in 4 million years it will finally eliminate the need for February 29th! Eclipses may be the Moon’s most-theatrical display, but to a scientist the real treasure is what the Moon can tell us about Solar System history. Have you ever wondered what you’re looking at when you look at the Moon in the night sky? Is the Moon’s forever-hidden far side different? Does the Moon have the same types of rocks as Earth? What did we find when we went there? Are we ever going back? In this talk, Dr. Elardo will take you on a tour of the geology of Earth’s Moon. We’ll take a stroll through what you can see, look at the fascinating features that you can’t see, dive into the Moon’s interior, jump into the past to find out how it came to be, and take a peek at what’s on the Moon’s horizon.

Dr. Stephen Elardo, Carnegie Geophysical Laboratory

Dr. Peter van Keken - When Earth Attacks: Causes and Consequences of a Tectonic Planet

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, Peter van Keken
Thursday, March 22, 2018 - 6:30pm to 7:45pm

A little over 50 years ago, the theory of plate tectonics emerged to provide a unifying theory for the dynamic behavior of the solid Earth as expressed by earthquakes, volcanoes, mountain building, and continental drift. In this talk, Dr. van Keken will discuss how our thinking of plate tectonics has evolved; how natural hazards are connected to the slow convective motion of the Earth’s interior; and how plate tectonics influences the longterm evolution of the Earth.

Dr. Peter van Keken: Department of Terrestrial Magnetism, Carnegie Science


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Dr. John Mulchaey - Eyes on the Universe: Carnegie’s Leadership in Astronomy Today

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, John Mulchaey
Thursday, April 19, 2018 - 6:30pm to 7:45pm

From the work of luminaries Edwin Hubble and Vera Rubin to the recent detection of a neutron star merger and the discovery of the most-distant black hole, Carnegie scientists have played a central role in our understanding of the universe. Dr. Mulchaey will describe how Carnegie’s early telescopes at Mt. Wilson helped launch modern astronomy and how astronomers are using our current facilities in Chile to address some of the biggest mysteries of the universe. Finally, he will describe his efforts to build the next-generation Giant Magellan Telescope.

Dr. John Mulchaey: Interim Co-President, Carnegie Science; Director and Crawford H. Greenewalt Chair, Carnegie Observatories


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Dr. Timothy Strobel - Harder, Better, Faster, Stronger: How High Pressure and Supercomputers Will Shape Materials of the Future

Carnegie Science, Carnegie Institution, Carnegie Institution for Science, Timothy Strobel
Thursday, May 24, 2018 - 6:30pm to 7:45pm

From stone to steel to silicon, materials shape the world in which we live. Nearly every aspect of our lives is governed by the availability of materials with specific properties, and new advanced materials are needed to address current societal issues. Using a combination of high-performance computation and advanced experimental synthesis, we now have unprecedented control over the design and fabrication of materials with application-specific properties. In this lecture, Dr. Strobel will provide an overview of recent discoveries – including new materials to revolutionize our use of solar energy and novel structures that are stronger than diamond – and will paint a picture of a new civilization era of materials by design.

Dr. Timothy Strobel: Geophysical Laboratory, Carnegie Science


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Deep Blue Planet

Thursday, October 18, 2018 - 6:30pm to 7:45pm

Earth is a water world. More than 70 percent of our planet's surface is covered in water, and its presence allowed for the emergence and sustenance of life. But from where did Earth's water originate? Why is our planet apparently so wet and why are other planets so dry? Water is not only prevalent on the outside of our planet, but there may be oceans of water in its interior, too. How much water exists inside Earth and how does it get down there and back out again? What is the deep Earth's role in regulating the water on the surface? Dr. Walter will investigate these questions as we probe our "Deep Blue Planet."

Dr. Michael Walter: Director, Geophysical Laboratory, Carnegie Institution for Science


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The Geodynamo: A Unique Window into the Dynamics of Earth’s Deep Interior

Thursday, November 8, 2018 - 6:30pm to 7:45pm

Earth's magnetic field is generated by convective motion in the liquid iron outer core, commonly referred to as the geodynamo.  The magnetic field has been protecting Earth from harmful charged particles for at least the last 2.5 billion years, and possibly longer.  In this talk Dr. Driscoll will discuss the physical mechanisms that produce the geomagnetic field, conduct a brief survey of planetary magnetism, and explore Earth’s rich paleomagnetic history preserved in ancient rocks, including polarity reversals, superchrons, paleointensity, and the impact of the solidification of the inner core.  He will highlight the pioneering contributions from the Department of Terrestrial Magnetism on early studies of geomagnetism.

Dr. Peter Driscoll: Staff Scientist, Department of Terrestrial Magnetism, Carnegie Institution for Science


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Addressing climate change with science-based energy solutions

Thursday, March 28, 2019 - 6:30pm to 7:45pm

As extreme weather, rising seas, and severe droughts bring home the reality of global climate change, we are increasingly aware of the world’s pressing need for carbon-free energy sources and reliable, affordable energy storage systems.

Already, we’re seeing the forefront of a new energy economy, with Denmark generating almost half of its power through wind energy and California moving toward its goal of operating on 100 percent clean energy by 2045. We also are gaining a deeper, more-nuanced understanding of the highly specific local impacts of pollution from shortened life expectancy to coral reef bleaching. But we still face daunting obstacles in our search for new materials and technologies that will allow us to generate and store the energy we need—while we attempt to repair the environmental damage we have inflicted on our planet.

To address this crisis, our scientists’ work must inform pragmatic, effective policies that will create effective incentives for utilities and consumers to shift away from dependence on fossil fuels and embrace a new energy future. These are enormous challenges that will require us to work together on an international scale and quickly pursue effective scientific energy solutions that will address the global climate crisis—while we still can.

Dr. Eric Isaacs: President, Carnegie Institution for Science


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The gravity of volcanoes: using gravity data to probe magma reservoirs

Thursday, April 25, 2019 - 6:30pm to 7:45pm

Gravity, the fundamental force that shaped our planet, varies across the Earth’s surface, both from place to place and over time. For more than three centuries, scientists have made gravity measurements to define the shape of the Earth. Today, very precise measurements of gravity provide crucial information on the mass distribution and transport within the planet. In this talk, Dr. Le Mével will highlight the long history of the determination of the gravity field, from the first field expeditions to the era of satellite measurements, and will discuss the evolution of the instrumentation. She will then show how gravity studies are used to image magmatic systems under volcanoes and their great potential for investigating magma dynamics leading up to eruptions.

Dr. Hélène Le Mével: Staff Scientist, Department of Terrestrial Magnetism, Carnegie Institution for Science


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Shocking minerals: From meteorite impacts to exoplanets

Thursday, May 23, 2019 - 6:30pm to 7:45pm

In shock-wave experiments, high-powered lasers or guns are used to send a supersonic pressure wave through a sample. This type of dynamic compression can generate immense pressure and allows for the study of impact phenomena in real time. These experiments have wide applications for Earth and planetary science, ranging from understanding the effects of meteorite impacts to studying the structure of planetary interiors. Dynamic experiments are short-lived, generally having a duration of tens of billionths of a second. This requires the development of ultrafast experiments. In this talk, Tracy will review new results using high-intensity pulsed x-rays to examine the crystal structure of shock-compressed minerals.

Dr. Sally June Tracy: Staff Scientist, Geophysical Laboratory, Carnegie Institution for Science


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Universal Life: The Search for Life Beyond the Solar System

Thursday, September 12, 2019 - 6:30pm to 7:45pm

We stand at an epochal moment in human history – we are about to learn if we are alone in the universe. The Kepler Space Telescope has shown that Earth-like worlds are commonplace. NASA is planning to spend billions of dollars on future space telescopes that will seek definitive proof of the existence and habitability, if not evidence of actual inhabitation, of rocky, Earth-like worlds around the nearest stars. Three large consortia are trying to beat NASA to this goal by planning and building the next generation of extremely large ground-based telescopes, including the Carnegie Institution’s Giant Magellan Telescope, now under construction in Chile. This talk will summarize the amazing discoveries that led us to this point, and discuss the competing visions for discovering life beyond our planetary system.

Dr. Alan Boss: Staff Scientist, Department of Terrestrial Magnetism, Carnegie Institution for Science


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The Magic and Mystery of Magnetic Resonance

Thursday, October 3, 2019 - 6:30pm to 7:45pm

The phenomenon of magnetic resonance was first revealed in the classic Stern-Gerlach experiment in 1922. Over the nearly 100 years and 10 Nobel Prizes that followed, magnetic resonance has developed into one of the most powerful analytical tools available to chemists, geochemists, physicists, molecular biologists, and materials scientists. The phenomenon of magnetic resonance also developed into one of the most useful medical diagnostic methods via Magnetic Resonance Imaging (MRI). In this talk George Cody will introduce and explain how Nuclear Magnetic Resonance (NMR) works without going deep into the physics. Cody will also explain how MRI works, why it is counterintuitive, and why it takes so long and is so noisy! Finally, he will provide examples of how he uses NMR to address important problems in geochemistry.

Dr. George Cody: Staff Scientist, Geophysical Laboratory, Carnegie Institution for Science


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The Biology of Corals, Basic Research and Environmental Health

Thursday, November 7, 2019 - 6:30pm to 7:45pm

Symbiosis refers to mutually beneficial interactions between different organisms. Endosymbiosis is a type of symbiosis in which one organism lives inside another organism. Endosymbiotic relationships evolve in a wide range of forms, from terrestrial plants to aquatic mollusks and corals. In recent decades, the breakdown of endosymbiosis between corals and their symbiotic algae, i.e. coral bleaching, due to climate change has led to massive coral death and consequently coral reef degradation. By developing and applying different tools, we have uncovered genes that define the symbiotic states of coral, which reveal insights into why coral recovery from bleaching is slow and difficult, and how we may be able to enhance corals' recovery from bleaching.

Dr. Yixian Zheng: Director, Department of Embryology, Carnegie Institution for Science


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The Earth's First Crust

Thursday, September 24, 2020 - 6:30pm to 7:30pm

Earth is unique amongst the rocky planets in having two very different types of crust. Continental crust is composed primarily of silica-rich rocks like the granite of your kitchen countertops. Oceanic crust is instead almost entirely a black magnesium and iron-rich volcanic rock, basalt, like that erupted in Hawaii. The continental crust juts above water because it is thick and granite is less dense than basalt so it floats higher on top of Earth’s interior. Oceanic crust sinks back into Earth’s interior on hundred-million-year timescales. In contrast, the buoyancy of continental crust allows it to survive longer at Earth’s surface. Even so, only a very small portion of Earth’s surface consists of rocks formed within half a billion years of Earth formation. Dr. Richard Carlson will discuss the continuing efforts to find these rare remnants of Earth’s oldest crust and what they can tell us about what our home planet was like in its infancy.

Dr. Richard Carlson: Director Carnegie Earth and Planets Laboratory


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A New Creation Story for the Earth and Moon

Thursday, November 12, 2020 - 6:30pm to 7:30pm

The origin of the Earth and Moon is one of science’s greatest mystery stories, complete with false starts and dead ends.

The Apollo missions shattered all the previous ideas about making the Moon. But the precious lunar samples contain a major clue to our planet’s creation: the Moon is Earth’s isotopic twin. The isotopes of different elements are like a planetary fingerprint: no two bodies are the same – except the Earth and Moon. After Apollo, a giant impact became the most likely explanation for the Moon, but it failed to explain this key observation.

Stewart will talk about the accidental discovery of a new type of astronomical object, called a synestia, that may save the idea of a giant impact and forever change the way you think about the birth of our planet.

The lecture will be held via Zoom and will be streamed live to the Earth and Planets Laboratory YouTube channel.