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- <b>ASTRONOMY COLLOQUIUM</b><br>Tracing the Cosmic Shutdown of Star Formation in Massive Galaxies
- <b>ASTRONOMY COLLOQUIUM</b><br>The Effects of Magnetic Field Morphology on the Determination of Oxygen and Iron Abundances in the Solar Photosphere
- <b>ASTRONOMY COLLOQUIUM</b><br>Star Formation Across Space
- <b>ASTRONOMY COLLOQUIUM</b><br>Lonely Galaxies: The Baryon Content of Isolated Dwarf Galaxies
- <b>ASTRONOMY COLLOQUIUM</b><br>Choose Your Own Adventure: Multiplicity of Planets Among the Smallest Stars
- <b>ASTRONOMY COLLOQUIUM</b><br>Why the Invisible Reservoir of Gas Around Galaxies Counts in Galaxy Evolution
- <b>ASTRONOMY COLLOQUIUM</b><br>A Galaxy-Scale Fountain of Cold Molecular Gas Pumped by a Black Hole
- ASTRONOMY COLLOQUIUM
- ASTRONOMY COLLOQUIUM<br>Better Living Through Computation: Exploring the First Generations of Galaxies with Large-Scale Simulations
- ASTRONOMY COLLOQUIUM<br>The Search for Earth 2.0
- ASTRONOMY COLLOQUIUM<br>The Fast and Furious Lives of High Velocity Clouds
- ASTRONOMY COLLOQUIUM<br>Supernovae as Drivers of Dust Evolution in Galaxies
- ASTRONOMY COLLOQUIUM<br>How to Measure the Composition of Planet-Forming Material
- ASTRONOMY COLLOQUIUM<br>Direct Imaging of Extrasolar Planets and the Gemini Planet Imager
- ASTRONOMY COLLOQUIUM<br>Blowing in the Quasar Wind: Feedback from Black Hole Outflows in Major Galaxy Mergers
- ASTRONOMY COLLOQUIUM<br>Magellan/MDM Colloquium: Department Members Share Their Current Work Using Magellan/MDM Observatories
- ASTRONOMY COLLOQUIUM<br>The Fisk-Vanderbilt Masters-to-PhD Bridge Program: A Model for Increasing Diversity at the PhD Level in Physics & Astronomy
- ASTRONOMY COLLOQUIUM<br>Science, Symphony, and the Northern Lights
- ASTRONOMY COLLOQUIUM<br>Observing the Formation of Planetary Diversity
- ASTRONOMY COLLOQUIUM<br>Lies, Damned Lies, and Statistics: Empirical Constraints on Theories of Planet Formation
- ASTRONOMY COLLOQUIUM<br>Black People in Astronomy: Why So Few?
- ASTRONOMY COLLOQUIUM <br> Hot on the Trail of Warm Planets Orbiting Cool Stars
- ASTRONOMY COLLOQUIUM<br>Galaxy Clusters as Cosmological and Astrophysical Probes
- ASTRONOMY COLLOQUIUM <br> Discovery of a Thorne-Zytkow Object Candidate in The Small Magellanic Cloud
- ASTRONOMY COLLOQUIUM<br>Where's the Matter? (Tales from the Milky Way's Destructive Past)
- ASTRONOMY COLLOQUIUM<br>Measuring the Mass-Radius Relation of Neutron Stars
- ASTRONOMY COLLOQUIUM <br> Accretion Disk Outbursts: MHD Simulations (Finally) Confront Reality
- ASTRONOMY COLLOQUIUM <br> The Observability of Recoiling Black Holes as Offset Quasars
- ASTRONOMY COLLOQUIUM<br>Black Hole Masses in Active Galaxies
- ASTRONOMY COLLOQUIUM<br>Using Multiwavelength Variability Studies to Probe the Disk-Jet Connection of Fermi Blazars
- ASTRONOMY COLLOQUIUM<br>X-ray Reverberation Mapping in AGN
- 3rd Annual Astronomy Undergraduate Poster Session
- ASTRONOMY COLLOQUIUM<br>High-Energy-Density Astrophysics in the Laboratory
- SPECIAL ASTRONOMY COLLOQUIUM<br>Ralph Baldwin Prize in Astrophysics and Space Sciences<br>Lonely Massive Stars</br>
- ASTRONOMY COLLOQUIUM<br>Live Fast Die Young: The Evolution of Massive Stars towards their Death</br>
- ASTRONOMY COLLOQUIUM<br>Watching a Little Gas Cloud on its Way into the Galactic Supermassive Black Hole
- ASTRONOMY COLLOQUIUM<br>Dwarf Galaxies as Cosmological Probes
- SPECIAL ASTRONOMY COLLOQUIUM<br>The Magellan and MDM Observatories / Michigan Astronomy
- ASTRONOMY COLLOQUIUM<br>Seeing Worlds in Grains of Sand
- ASTRONOMY COLLOQUIUM<br>Mohler Prize Lecture<br>Lighting up the Universe: Witnessing Cosmic Dawn</br>
- ASTRONOMY COLLOQUIUM<br>The ALFALFA Census of Gas-Bearing Galaxies at z=0</br>
- ASTRONOMY COLLOQUIUM<br>Accretion Disk Outbursts: MHD Simulations (Finally) Confront Reality
- ASTRONOMY COLLOQUIUM<br>3D Spectroscopy of Giant H II Regions in Nearby Spiral Galaxies</br>
- ASTRONOMY COLLOQUIUM<br>Star Clusters and High Mass X-Ray Binaries in Nearby Spirals, Mergers, and Starburst Galaxies
- PUBLIC ASTRONOMY DISTINGUISHED ALUMNUS COLLOQUIUM | Cracking the Cosmic Code
- ASTRONOMY DISTINGUISHED ALUMNUS COLLOQUIUM
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Many observed triple systems in our Universe are in a hierarchical configuration: two objects orbit each other in a relatively tight inner binary while the third object is on a much wider orbit. Furthermore, the secular approximation for the evolution of hierarchical triple body systems has been proven to be very useful in many astrophysical contexts, from planetary to triple-star systems and even black holes. In this approximation the orbits may change shape and orientation, on timescales longer than the orbital periods, but the semi-major axes are constant. In early studies of hierarchical secular three-body systems (Kozai 1962; Lidov 1962), the wider orbit was set to be circular and one of the tight binary members was assumed to be a test (massless) particle. In this situation, the component of the tight orbit’s angular momentum along the total angular momentum is conserved, and the lowest order of the approximation (i.e., the quadrupole approximation) is valid. I will discussed recent developments that showed that considering systems beyond the test particle approximation, or circular orbits, requires the next level of approximation for a correct representation of the physics, called the octupole-level. This leads to qualitative different behavior of the system. In this case, the angular momenta component of the tight and wide orbits along the total angular momentum is not conserved. Most interestingly, at this level of approximation, for an eccentric wide orbit, the tight orbit can reach extremely high eccentricities and undergo chaotic flips of its orientation. This behavior has important implications to the evolution of many systems, and I will present some nominal examples, such as retrograde hot Jupiters, blue stragglers and low-mass X-ray binaries.
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