Courtney D. Dressing
Total Page：16
File Type：pdf, Size：1020Kb
Load more
Recommended publications
-
Using Kepler Systems to Constrain the Frequency and Severity of Dynamical Effects on Habitable Planets Alexander James Mustill Melvyn B
Using Kepler systems to constrain the frequency and severity of dynamical effects on habitable planets Alexander James Mustill Melvyn B. Davies Anders Johansen Dynamical instability bad for habitability • Excitation of eccentricity can shift HZ or cause extreme seasons (Spiegel+10, Dressing+10) • Planets may be scattered out of HZ • Planet-planet collisions may remove biospheres, atmospheres, water • Earth-like planets may be eaten by Neptunes/Jupiters Strong dynamical effects: scattering and Kozai • Scattering: closely-spaced giant planets excite each others’ eccentricities (Chatterjee+08) • Kozai: inclined external perturber (e.g. binary) can cause very large eccentricity fluctuations (Kozai 62, Lidov 62, Naoz 16) Relevance of inner systems to HZ • If you can • form a hot Jupiter through high-eccentricity migration • damage a Kepler system at few tenths of an au • you will damage the habitable zone too Relevance of inner systems intrinsically • Large number of single-candidate systems found by Kepler relative to multiples • Is this left over from formation? Or do the multiples evolve into singles through dynamics? (Johansen+12) • Informs models of planet formation • all the Kepler systems are interestingly different to the Solar system, but do we have two interestingly different channels of planet formation or only one? What do we know about the prevalence of strong dynamical effects? • So far know little about planets in HZ • What we do know: • Violent dynamical history strong contender for hot Jupiter migration • Many giants have high -
Lurking in the Shadows: Wide-Separation Gas Giants As Tracers of Planet Formation
Lurking in the Shadows: Wide-Separation Gas Giants as Tracers of Planet Formation Thesis by Marta Levesque Bryan In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California 2018 Defended May 1, 2018 ii © 2018 Marta Levesque Bryan ORCID: [0000-0002-6076-5967] All rights reserved iii ACKNOWLEDGEMENTS First and foremost I would like to thank Heather Knutson, who I had the great privilege of working with as my thesis advisor. Her encouragement, guidance, and perspective helped me navigate many a challenging problem, and my conversations with her were a consistent source of positivity and learning throughout my time at Caltech. I leave graduate school a better scientist and person for having her as a role model. Heather fostered a wonderfully positive and supportive environment for her students, giving us the space to explore and grow - I could not have asked for a better advisor or research experience. I would also like to thank Konstantin Batygin for enthusiastic and illuminating discussions that always left me more excited to explore the result at hand. Thank you as well to Dimitri Mawet for providing both expertise and contagious optimism for some of my latest direct imaging endeavors. Thank you to the rest of my thesis committee, namely Geoff Blake, Evan Kirby, and Chuck Steidel for their support, helpful conversations, and insightful questions. I am grateful to have had the opportunity to collaborate with Brendan Bowler. His talk at Caltech my second year of graduate school introduced me to an unexpected population of massive wide-separation planetary-mass companions, and lead to a long-running collaboration from which several of my thesis projects were born. -
Dynamics of the Terrestrial Planets from a Large Number of N-Body Simulations ∗ Rebecca A
Earth and Planetary Science Letters 392 (2014) 28–38 Contents lists available at ScienceDirect Earth and Planetary Science Letters www.elsevier.com/locate/epsl Dynamics of the terrestrial planets from a large number of N-body simulations ∗ Rebecca A. Fischer , Fred J. Ciesla Department of the Geophysical Sciences, University of Chicago, 5734 S Ellis Ave, Chicago, IL 60637, USA article info abstract Article history: The agglomeration of planetary embryos and planetesimals was the final stage of terrestrial planet Received 6 September 2013 formation. This process is modeled using N-body accretion simulations, whose outcomes are tested by Received in revised form 26 January 2014 comparing to observed physical and chemical Solar System properties. The outcomes of these simulations Accepted 3 February 2014 are stochastic, leading to a wide range of results, which makes it difficult at times to identify the full Availableonline25February2014 range of possible outcomes for a given dynamic environment. We ran fifty high-resolution simulations Editor: T. Elliott each with Jupiter and Saturn on circular or eccentric orbits, whereas most previous studies ran an Keywords: order of magnitude fewer. This allows us to better quantify the probabilities of matching various accretion observables, including low probability events such as Mars formation, and to search for correlations N-body simulations between properties. We produce many good Earth analogues, which provide information about the mass terrestrial planets evolution and provenance of the building blocks of the Earth. Most observables are weakly correlated Mars or uncorrelated, implying that individual evolutionary stages may reflect how the system evolved even late veneer if models do not reproduce all of the Solar System’s properties at the end. -
The Tierras Observatory: an Ultra-Precise Photometer to Characterize Nearby Terrestrial Exoplanets
The Tierras Observatory: An ultra-precise photometer to characterize nearby terrestrial exoplanets Juliana Garc´ıa-Mej´ıaa, David Charbonneaua, Daniel Fabricanta, Jonathan M. Irwina, Robert Fataa, Joseph M. Zajaca, and Peter E. Dohertya aCenter for Astrophysics Harvard and Smithsonian, 60 Garden Street, Cambridge MA j ABSTRACT We report on the status of the Tierras Observatory, a refurbished 1.3-m ultra-precise fully-automated photometer located at the F. L. Whipple Observatory atop Mt. Hopkins, Arizona. Tierras is designed to limit systematic errors, notably precipitable water vapor (PWV), to 250 ppm, enabling the characterization of terrestrial planet transits orbiting < 0:3 R stars, as well as the potential discovery of exo-moons and exo-rings. The design choices that will enable our science goals include: a four-lens focal reducer and field-flattener to increase the field-of-view of the telescope from a 11:940 to a 0:48◦ side; a custom narrow bandpass (40:2 nm FWHM) filter centered around 863:5 nm to minimize PWV errors known to limit ground-based photometry of red dwarfs; and a deep-depletion 4K 4K CCD with a 300ke- full well and QE> 85% in our bandpass, operating in frame transfer mode. We are also× pursuing the design of a set of baffles to minimize the significant amount of scattered light reaching the image plane. Tierras will begin science operations in early 2021. Keywords: ultra-precise photometry, terrestrial planet detection, exoplanet instrumentation, transit method 1. INTRODUCTION The construction of observatories tailor-built to routinely achieve precise photometry from the ground is mo- tivated by the multitude of exoplanetary and stellar phenomena whose exploration will be enabled with high- cadence, ultra-precise time series of diverse stellar targets. -
KEPLER-21B: a 1.6 Rearth PLANET TRANSITING the BRIGHT OSCILLATING F SUBGIANT STAR HD 179070 Steve B
The Astrophysical Journal, 746:123 (18pp), 2012 February 20 doi:10.1088/0004-637X/746/2/123 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. ∗ KEPLER-21b: A 1.6 REarth PLANET TRANSITING THE BRIGHT OSCILLATING F SUBGIANT STAR HD 179070 Steve B. Howell1,2,36, Jason F. Rowe2,3,36, Stephen T. Bryson2, Samuel N. Quinn4, Geoffrey W. Marcy5, Howard Isaacson5, David R. Ciardi6, William J. Chaplin7, Travis S. Metcalfe8, Mario J. P. F. G. Monteiro9, Thierry Appourchaux10, Sarbani Basu11, Orlagh L. Creevey12,13, Ronald L. Gilliland14, Pierre-Olivier Quirion15, Denis Stello16, Hans Kjeldsen17,Jorgen¨ Christensen-Dalsgaard17, Yvonne Elsworth7, Rafael A. Garc´ıa18, Gunter¨ Houdek19, Christoffer Karoff7, Joanna Molenda-Zakowicz˙ 20, Michael J. Thompson8, Graham A. Verner7,21, Guillermo Torres4, Francois Fressin4, Justin R. Crepp23, Elisabeth Adams4, Andrea Dupree4, Dimitar D. Sasselov4, Courtney D. Dressing4, William J. Borucki2, David G. Koch2, Jack J. Lissauer2, David W. Latham4, Lars A. Buchhave22,35, Thomas N. Gautier III24, Mark Everett1, Elliott Horch25, Natalie M. Batalha26, Edward W. Dunham27, Paula Szkody28,36, David R. Silva1,36, Ken Mighell1,36, Jay Holberg29,36,Jeromeˆ Ballot30, Timothy R. Bedding16, Hans Bruntt12, Tiago L. Campante9,17, Rasmus Handberg17, Saskia Hekker7, Daniel Huber16, Savita Mathur8, Benoit Mosser31, Clara Regulo´ 12,13, Timothy R. White16, Jessie L. Christiansen3, Christopher K. Middour32, Michael R. Haas2, Jennifer R. Hall32,JonM.Jenkins3, Sean McCaulif32, Michael N. Fanelli33, Craig -
Curriculum Vitae
CURRICULUM VITAE Smadar Naoz September 2021 Contact University of California Los Angeles, Information Department of Physics & Astronomy 30 Portola Plaza, Box 951547 E-mail: [email protected] Los Angeles, CA 90095 WWW: http://www.astro.ucla.edu/∼snaoz/ Research Dynamics of planetary, stellar and black hole systems, which include formation of Hot Jupiters, Interests globular clusters, spiral structure, compact objects etc. Cosmology, structure formation in the early Universe, reionization and 21cm fluctuations. Education Tel Aviv University, Tel Aviv, Israel Ph.D. in Physics, January 2010 Hebrew University of Jerusalem, Jerusalem, Israel M.S. in Physics, Magna Cum Laude, 2004 B.S. in Physics 2002 Positions University of California, Los Angeles Associate professor since July 2019 Howard & Astrid Preston Term Chair in Astrophysics since July 2018 Assistant professor 2014-2019 Harvard Smithsonian CfA, Institute for Theory and Computation Einstein Fellow, September 2012 { June 2014 ITC Fellow, September 2011 { August 2012 Northwestern University, CIERA Gruber Fellow, September 2010 { August 2011 Postdoctoral associate in theoretical astrophysics, January 2010 { August 2010 Scholarships Helen B. Warner Prize, awarded by the American Astronomical Society, 2020 Honors and Scialog fellow, and accepted proposal, Signatures of Life in the Universe, 2020/2021 (conference Awards postponed to 2021 due to COVID-19) Career Commitment to Diversity, Equity and Inclusion Award, given by UCLA Academic Senate 2019. For other diversity awards, see xDEI. Hellman Fellows Award, awarded by Hellman Fellows Program, aimed to support the research of promising Assistant Professors who show capacity for great distinction in their research, June 2017 Multiple departmental teaching awards 2015-2019, see xTeaching, for details Sloan Research Fellowships awarded by the Alfred P. -
Dynamical Models of Terrestrial Planet Formation
Dynamical Models of Terrestrial Planet Formation Jonathan I. Lunine, LPL, The University of Arizona, Tucson AZ USA, 85721. [email protected] David P. O’Brien, Planetary Science Institute, Tucson AZ USA 85719 Sean N. Raymond, CASA, University of Colorado, Boulder CO USA 80302 Alessandro Morbidelli, Obs. de la Coteˆ d’Azur, Nice, F-06304 France Thomas Quinn, Department of Astronomy, University of Washington, Seattle USA 98195 Amara L. Graps, SWRI, Boulder CO USA 80302 Revision submitted to Advanced Science Letters May 23, 2009 Abstract We review the problem of the formation of terrestrial planets, with particular emphasis on the interaction of dynamical and geochemical models. The lifetime of gas around stars in the process of formation is limited to a few million years based on astronomical observations, while isotopic dating of meteorites and the Earth-Moon system suggest that perhaps 50-100 million years were required for the assembly of the Earth. Therefore, much of the growth of the terrestrial planets in our own system is presumed to have taken place under largely gas-free conditions, and the physics of terrestrial planet formation is dominated by gravitational interactions and collisions. The ear- liest phase of terrestrial-planet formation involve the growth of km-sized or larger planetesimals from dust grains, followed by the accumulations of these planetesimals into ∼100 lunar- to Mars- mass bodies that are initially gravitationally isolated from one-another in a swarm of smaller plan- etesimals, but eventually grow to the point of significantly perturbing one-another. The mutual perturbations between the embryos, combined with gravitational stirring by Jupiter, lead to orbital crossings and collisions that drive the growth to Earth-sized planets on a timescale of 107 − 108 years. -
Three-Body Capture of Irregular Satellites: Application to Jupiter
Icarus 208 (2010) 824–836 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Three-body capture of irregular satellites: Application to Jupiter Catherine M. Philpott a,*, Douglas P. Hamilton a, Craig B. Agnor b a Department of Astronomy, University of Maryland, College Park, MD 20742-2421, USA b Astronomy Unit, School of Mathematical Sciences, Queen Mary University of London, London E14NS, UK article info abstract Article history: We investigate a new theory of the origin of the irregular satellites of the giant planets: capture of one Received 19 October 2009 member of a 100-km binary asteroid after tidal disruption. The energy loss from disruption is sufficient Revised 24 March 2010 for capture, but it cannot deliver the bodies directly to the observed orbits of the irregular satellites. Accepted 26 March 2010 Instead, the long-lived capture orbits subsequently evolve inward due to interactions with a tenuous cir- Available online 7 April 2010 cumplanetary gas disk. We focus on the capture by Jupiter, which, due to its large mass, provides a stringent test of our model. Keywords: We investigate the possible fates of disrupted bodies, the differences between prograde and retrograde Irregular satellites captures, and the effects of Callisto on captured objects. We make an impulse approximation and discuss Jupiter, Satellites Planetary dynamics how it allows us to generalize capture results from equal-mass binaries to binaries with arbitrary mass Satellites, Dynamics ratios. Jupiter We find that at Jupiter, binaries offer an increase of a factor of 10 in the capture rate of 100-km objects as compared to single bodies, for objects separated by tens of radii that approach the planet on relatively low-energy trajectories. -
FY13 High-Level Deliverables
National Optical Astronomy Observatory Fiscal Year Annual Report for FY 2013 (1 October 2012 – 30 September 2013) Submitted to the National Science Foundation Pursuant to Cooperative Support Agreement No. AST-0950945 13 December 2013 Revised 18 September 2014 Contents NOAO MISSION PROFILE .................................................................................................... 1 1 EXECUTIVE SUMMARY ................................................................................................ 2 2 NOAO ACCOMPLISHMENTS ....................................................................................... 4 2.1 Achievements ..................................................................................................... 4 2.2 Status of Vision and Goals ................................................................................. 5 2.2.1 Status of FY13 High-Level Deliverables ............................................ 5 2.2.2 FY13 Planned vs. Actual Spending and Revenues .............................. 8 2.3 Challenges and Their Impacts ............................................................................ 9 3 SCIENTIFIC ACTIVITIES AND FINDINGS .............................................................. 11 3.1 Cerro Tololo Inter-American Observatory ....................................................... 11 3.2 Kitt Peak National Observatory ....................................................................... 14 3.3 Gemini Observatory ........................................................................................ -
Blue Dots Team Transits Working Group Review
**FULL TITLE** ASP Conference Series, Vol. **VOLUME**, **YEAR OF PUBLICATION** **NAMES OF EDITORS** Blue Dots Team Transits Working Group Review A. Sozzetti1, C. Afonso2, R. Alonso3, D. L. Blank4, C. Catala5, H. Deeg6, J. L. Grenfell7, C. Hellier8, D. W. Latham9, D. Minniti10, F. Pont11, and H. Rauer12 Abstract. Transiting planet systems offer an unique opportunity to obser- vationally constrain proposed models of the interiors (radius, composition) and atmospheres (chemistry, dynamics) of extrasolar planets. The spectacular suc- cesses of ground-based transit surveys (more than 60 transiting systems known to-date) and the host of multi-wavelength, spectro-photometric follow-up stud- ies, carried out in particular by HST and Spitzer, have paved the way to the next generation of transit search projects, which are currently ongoing (CoRoT, Kepler), or planned. The possibility of detecting and characterizing transiting Earth-sized planets in the habitable zone of their parent stars appears tanta- lizingly close. In this contribution we briefly review the power of the transit technique for characterization of extrasolar planets, summarize the state of the art of both ground-based and space-borne transit search programs, and illustrate how the science of planetary transits fits within the Blue Dots perspective. 1. Introduction Within the framework of the Blue-Dots Team (BDT) initiative (http://www.blue-dots.net/), the primary goal of the Transits Working Group (TWG) is to gauge the potential and limitations of transit photometry (and follow-up measurements) as a tool 1INAF - Osservatorio Astronomico di Torino, Strada Osservatorio 20, I-10025 Pino Torinese, Italy 2Max Planck Institute for Astronomy, K¨onigstuhl 17, 69117 Heidelberg, Germany 3Observatoire de Gen´eve, Universit´ede Gen`eve, 51 Ch. -
Sized Exoplanet Thomas Barclay1,2, Jason F
A sub-Mercury-sized exoplanet Thomas Barclay1,2, Jason F. Rowe1,3, Jack J. Lissauer1, Daniel Huber1,4, François Fressin5, Steve B. Howell1, Stephen T. Bryson1, William J. Chaplin6, Jean-Michel Désert5, Eric D. Lopez7, Geoffrey W. Marcy8, Fergal Mullally1,3, Darin Ragozzine5,9, Guillermo Torres5, Elisabeth R. Adams5, Eric Agol10, David Barrado11,12, Sarbani Basu13, Timothy R. Bedding14, Lars A. Buchhave15,16, David Charbonneau5, Jessie L. Christiansen1,3, Jørgen Christensen-Dalsgaard17, David Ciardi18, William D. Cochran19, Andrea K. Dupree5, Yvonne Elsworth6, Mark Everett20, Debra A. Fischer13, Eric B. Ford9, Jonathan J. Fortney7, John C. Geary5, Michael R. Haas1, Rasmus Handberg17, Saskia Hekker6,21, Christopher E. Henze1, Elliott Horch22, Andrew W. Howard23, Roger C. Hunter1, Howard Isaacson8, Jon M. Jenkins1,3, Christoffer Karoff17, Steven D. Kawaler24, Hans Kjeldsen17, Todd C. Klaus25, David W. Latham5, Jie Li1,3, Jorge Lillo-Box12, Mikkel N. Lund17, Mia Lundkvist17, Travis S. Metcalfe26, Andrea Miglio6, Robert L. Morris1,3, Elisa V. Quintana1,3, Dennis Stello14, Jeffrey C. Smith1,3, Martin Still1,2, & Susan E. Thompson1,3 1 NASA Ames Research Center, Moffett Field, CA 94035, USA 2 Bay Area Environmental Research Institute, 596 First St West, Sonoma, CA 95476, USA 3 SETI Institute, 189 Bernardo Ave, Mountain View, CA 94043, USA 4 NASA Postdoctoral Program Fellow 5 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 6 School of Physics and Astronomy, University of Birmingham, Edgbaston, B15 2TT, UK 7 Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064, USA 8 Department of Astronomy, UC Berkeley, Berkeley, CA 94720, USA 9 Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111, USA 10 Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195, USA 11 Calar Alto Observatory, Centro Astronómico Hispano Alemán, C/ Jesús Durbán Remón, E- 04004 Almería, Spain 12 Depto. -
Research Paper in Nature
LETTER doi:10.1038/nature22055 1 A temperate rocky super-Earth transiting a nearby cool star Jason A. Dittmann1, Jonathan M. Irwin1, David Charbonneau1, Xavier Bonfils2,3, Nicola Astudillo-Defru4, Raphaëlle D. Haywood1, Zachory K. Berta-Thompson5, Elisabeth R. Newton6, Joseph E. Rodriguez1, Jennifer G. Winters1, Thiam-Guan Tan7, Jose-Manuel Almenara2,3,4, François Bouchy8, Xavier Delfosse2,3, Thierry Forveille2,3, Christophe Lovis4, Felipe Murgas2,3,9, Francesco Pepe4, Nuno C. Santos10,11, Stephane Udry4, Anaël Wünsche2,3, Gilbert A. Esquerdo1, David W. Latham1 & Courtney D. Dressing12 15 16,17 M dwarf stars, which have masses less than 60 per cent that of Ks magnitude and empirically determined stellar relationships , the Sun, make up 75 per cent of the population of the stars in the we estimate the stellar mass to be 14.6% that of the Sun and the stellar Galaxy1. The atmospheres of orbiting Earth-sized planets are radius to be 18.6% that of the Sun. We estimate the metal content of the observationally accessible via transmission spectroscopy when star to be approximately half that of the Sun ([Fe/H] = −0.24 ± 0.10; all the planets pass in front of these stars2,3. Statistical results suggest errors given in the text are 1σ), and we measure the rotational period that the nearest transiting Earth-sized planet in the liquid-water, of the star to be 131 days from our long-term photometric monitoring habitable zone of an M dwarf star is probably around 10.5 parsecs (see Methods). away4. A temperate planet has been discovered orbiting Proxima On 15 September 2014 ut, MEarth-South identified a potential Centauri, the closest M dwarf5, but it probably does not transit and transit in progress around LHS 1140, and automatically commenced its true mass is unknown.