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A Review of Possible Planetary Atmospheres in the TRAPPIST-1 System
Space Sci Rev (2020) 216:100 https://doi.org/10.1007/s11214-020-00719-1 A Review of Possible Planetary Atmospheres in the TRAPPIST-1 System Martin Turbet1 · Emeline Bolmont1 · Vincent Bourrier1 · Brice-Olivier Demory2 · Jérémy Leconte3 · James Owen4 · Eric T. Wolf5 Received: 14 January 2020 / Accepted: 4 July 2020 / Published online: 23 July 2020 © The Author(s) 2020 Abstract TRAPPIST-1 is a fantastic nearby (∼39.14 light years) planetary system made of at least seven transiting terrestrial-size, terrestrial-mass planets all receiving a moderate amount of irradiation. To date, this is the most observationally favourable system of po- tentially habitable planets known to exist. Since the announcement of the discovery of the TRAPPIST-1 planetary system in 2016, a growing number of techniques and approaches have been used and proposed to characterize its true nature. Here we have compiled a state- of-the-art overview of all the observational and theoretical constraints that have been ob- tained so far using these techniques and approaches. The goal is to get a better understanding of whether or not TRAPPIST-1 planets can have atmospheres, and if so, what they are made of. For this, we surveyed the literature on TRAPPIST-1 about topics as broad as irradiation environment, planet formation and migration, orbital stability, effects of tides and Transit Timing Variations, transit observations, stellar contamination, density measurements, and numerical climate and escape models. Each of these topics adds a brick to our understand- ing of the likely—or on the contrary unlikely—atmospheres of the seven known planets of the system. -
Abstracts Connecting to the Boston University Network
20th Cambridge Workshop: Cool Stars, Stellar Systems, and the Sun July 29 - Aug 3, 2018 Boston / Cambridge, USA Abstracts Connecting to the Boston University Network 1. Select network ”BU Guest (unencrypted)” 2. Once connected, open a web browser and try to navigate to a website. You should be redirected to https://safeconnect.bu.edu:9443 for registration. If the page does not automatically redirect, go to bu.edu to be brought to the login page. 3. Enter the login information: Guest Username: CoolStars20 Password: CoolStars20 Click to accept the conditions then log in. ii Foreword Our story starts on January 31, 1980 when a small group of about 50 astronomers came to- gether, organized by Andrea Dupree, to discuss the results from the new high-energy satel- lites IUE and Einstein. Called “Cool Stars, Stellar Systems, and the Sun,” the meeting empha- sized the solar stellar connection and focused discussion on “several topics … in which the similarity is manifest: the structures of chromospheres and coronae, stellar activity, and the phenomena of mass loss,” according to the preface of the resulting, “Special Report of the Smithsonian Astrophysical Observatory.” We could easily have chosen the same topics for this meeting. Over the summer of 1980, the group met again in Bonas, France and then back in Cambridge in 1981. Nearly 40 years on, I am comfortable saying these workshops have evolved to be the premier conference series for cool star research. Cool Stars has been held largely biennially, alternating between North America and Europe. Over that time, the field of stellar astro- physics has been upended several times, first by results from Hubble, then ROSAT, then Keck and other large aperture ground-based adaptive optics telescopes. -
Monday, November 13, 2017 WHAT DOES IT MEAN to BE HABITABLE? 8:15 A.M. MHRGC Salons ABCD 8:15 A.M. Jang-Condell H. * Welcome C
Monday, November 13, 2017 WHAT DOES IT MEAN TO BE HABITABLE? 8:15 a.m. MHRGC Salons ABCD 8:15 a.m. Jang-Condell H. * Welcome Chair: Stephen Kane 8:30 a.m. Forget F. * Turbet M. Selsis F. Leconte J. Definition and Characterization of the Habitable Zone [#4057] We review the concept of habitable zone (HZ), why it is useful, and how to characterize it. The HZ could be nicknamed the “Hunting Zone” because its primary objective is now to help astronomers plan observations. This has interesting consequences. 9:00 a.m. Rushby A. J. Johnson M. Mills B. J. W. Watson A. J. Claire M. W. Long Term Planetary Habitability and the Carbonate-Silicate Cycle [#4026] We develop a coupled carbonate-silicate and stellar evolution model to investigate the effect of planet size on the operation of the long-term carbon cycle, and determine that larger planets are generally warmer for a given incident flux. 9:20 a.m. Dong C. F. * Huang Z. G. Jin M. Lingam M. Ma Y. J. Toth G. van der Holst B. Airapetian V. Cohen O. Gombosi T. Are “Habitable” Exoplanets Really Habitable? A Perspective from Atmospheric Loss [#4021] We will discuss the impact of exoplanetary space weather on the climate and habitability, which offers fresh insights concerning the habitability of exoplanets, especially those orbiting M-dwarfs, such as Proxima b and the TRAPPIST-1 system. 9:40 a.m. Fisher T. M. * Walker S. I. Desch S. J. Hartnett H. E. Glaser S. Limitations of Primary Productivity on “Aqua Planets:” Implications for Detectability [#4109] While ocean-covered planets have been considered a strong candidate for the search for life, the lack of surface weathering may lead to phosphorus scarcity and low primary productivity, making aqua planet biospheres difficult to detect. -
The TOI-763 System: Sub-Neptunes Orbiting a Sun-Like Star
MNRAS 000,1–14 (2020) Preprint 31 August 2020 Compiled using MNRAS LATEX style file v3.0 The TOI-763 system: sub-Neptunes orbiting a Sun-like star M. Fridlund1;2?, J. Livingston3, D. Gandolfi4, C. M. Persson2, K. W. F. Lam5, K. G. Stassun6, C. Hellier 7, J. Korth8, A. P. Hatzes9, L. Malavolta10, R. Luque11;12, S. Redfield 13, E. W. Guenther9, S. Albrecht14, O. Barragan15, S. Benatti16, L. Bouma17, J. Cabrera18, W.D. Cochran19;20, Sz. Csizmadia18, F. Dai21;17, H. J. Deeg11;12, M. Esposito9, I. Georgieva2, S. Grziwa8, L. González Cuesta11;12, T. Hirano22, J. M. Jenkins23, P. Kabath24, E. Knudstrup14, D.W. Latham25, S. Mathur11;12, S. E. Mullally32, N. Narita26;27;28;29;11, G. Nowak11;12, A. O. H. Olofsson 2, E. Palle11;12, M. Pätzold8, E. Pompei30, H. Rauer18;5;38, G. Ricker21, F. Rodler30, S. Seager21;31;32, L. M. Serrano4, A. M. S. Smith18, L. Spina33, J. Subjak34;24, P. Tenenbaum35, E.B. Ting23, A. Vanderburg39, R. Vanderspek21, V. Van Eylen36, S. Villanueva21, J. N. Winn17 Authors’ affiliations are shown at the end of the manuscript Accepted XXX. Received YYY; in original form ZZZ ABSTRACT We report the discovery of a planetary system orbiting TOI-763 (aka CD-39 7945), a V = 10:2, high proper motion G-type dwarf star that was photometrically monitored by the TESS space mission in Sector 10. We obtain and model the stellar spectrum and find an object slightly smaller than the Sun, and somewhat older, but with a similar metallicity. Two planet candidates were found in the light curve to be transiting the star. -
Spectra As Windows Into Exoplanet Atmospheres
SPECIAL FEATURE: PERSPECTIVE PERSPECTIVE SPECIAL FEATURE: Spectra as windows into exoplanet atmospheres Adam S. Burrows1 Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 Edited by Neta A. Bahcall, Princeton University, Princeton, NJ, and approved December 2, 2013 (received for review April 11, 2013) Understanding a planet’s atmosphere is a necessary condition for understanding not only the planet itself, but also its formation, structure, evolution, and habitability. This requirement puts a premium on obtaining spectra and developing credible interpretative tools with which to retrieve vital planetary information. However, for exoplanets, these twin goals are far from being realized. In this paper, I provide a personal perspective on exoplanet theory and remote sensing via photometry and low-resolution spectroscopy. Although not a review in any sense, this paper highlights the limitations in our knowledge of compositions, thermal profiles, and the effects of stellar irradiation, focusing on, but not restricted to, transiting giant planets. I suggest that the true function of the recent past of exoplanet atmospheric research has been not to constrain planet properties for all time, but to train a new generation of scientists who, by rapid trial and error, are fast establishing a solid future foundation for a robust science of exoplanets. planetary science | characterization The study of exoplanets has increased expo- by no means commensurate with the effort exoplanetology, and this expectation is in part nentially since 1995, a trend that in the short expended. true. The solar system has been a great, per- term shows no signs of abating. Astronomers An important aspect of exoplanets that haps necessary, teacher. -
Similarities in Body Size Distributions of Small-Bodied Flying Vertebrates
Evolutionary Ecology Research, 2004, 6: 783–797 Similarities in body size distributions of small-bodied flying vertebrates Brian A. Maurer,* James H. Brown, Tamar Dayan, Brian J. Enquist, S.K. Morgan Ernest, Elizabeth A. Hadly, John P. Haskell, David Jablonski, Kate E. Jones, Dawn M. Kaufman, S. Kathleen Lyons, Karl J. Niklas, Warren P. Porter, Kaustuv Roy, Felisa A. Smith, Bruce Tiffney and Michael R. Willig National Center for Ecological Analysis and Synthesis (NCEAS), Working Group on Body Size in Ecology and Paleoecology, 735 State Street, Suite 300, Santa Barbara, CA 93101-5504, USA ABSTRACT Since flight imposes physical constraints on the attributes of a flying organism, it is expected that the distribution of body sizes within clades of small-bodied flying vertebrates should share a similar pattern that reflects these constraints. We examined patterns in similarities of body mass distributions among five clades of small-bodied endothermic vertebrates (Passeriformes, Apodiformes + Trochiliformes, Chiroptera, Insectivora, Rodentia) to examine the extent to which these distributions are congruent among the clades that fly as opposed to those that do not fly. The body mass distributions of three clades of small-bodied flying vertebrates show significant divergence from the distributions of their sister clades. We examined two alternative hypotheses for similarities among the size frequency distributions of the five clades. The hypothesis of functional symmetry corresponds to patterns of similarity expected if body mass distributions of flying clades are constrained by similar or identical functional limitations. The hypothesis of phylogenetic symmetry corresponds to patterns of similarity expected if body mass distributions reflect phylogenetic relationships among clades. -
Exoplanet Exploration Collaboration Initiative TP Exoplanets Final Report
EXO Exoplanet Exploration Collaboration Initiative TP Exoplanets Final Report Ca Ca Ca H Ca Fe Fe Fe H Fe Mg Fe Na O2 H O2 The cover shows the transit of an Earth like planet passing in front of a Sun like star. When a planet transits its star in this way, it is possible to see through its thin layer of atmosphere and measure its spectrum. The lines at the bottom of the page show the absorption spectrum of the Earth in front of the Sun, the signature of life as we know it. Seeing our Earth as just one possibly habitable planet among many billions fundamentally changes the perception of our place among the stars. "The 2014 Space Studies Program of the International Space University was hosted by the École de technologie supérieure (ÉTS) and the École des Hautes études commerciales (HEC), Montréal, Québec, Canada." While all care has been taken in the preparation of this report, ISU does not take any responsibility for the accuracy of its content. Electronic copies of the Final Report and the Executive Summary can be downloaded from the ISU Library website at http://isulibrary.isunet.edu/ International Space University Strasbourg Central Campus Parc d’Innovation 1 rue Jean-Dominique Cassini 67400 Illkirch-Graffenstaden Tel +33 (0)3 88 65 54 30 Fax +33 (0)3 88 65 54 47 e-mail: [email protected] website: www.isunet.edu France Unless otherwise credited, figures and images were created by TP Exoplanets. Exoplanets Final Report Page i ACKNOWLEDGEMENTS The International Space University Summer Session Program 2014 and the work on the -
Arxiv:1610.05765V3 [Astro-Ph.EP] 27 Feb 2017 3.3 Microlensing and Direct Imaging
The Habitability of Planets Orbiting M-dwarf Stars Aomawa L. Shields1;2;4, Sarah Ballard3, John Asher Johnson4 1University of California, Irvine, Department of Physics and Astronomy, 4129 Frederick Reines Hall, Irvine, CA 92697, USA 2University of California, Los Angeles, Department of Physics and Astronomy, Box 951547, Los Angeles, CA 90095, USA 3Massachusetts Institute of Technology, 77 Massachusetts Ave, 37-241, Cambridge, MA 02139, USA 4Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA Abstract The prospects for the habitability of M-dwarf planets have long been debated, due to key differences between the unique stellar and planetary environments around these low-mass stars, as compared to hotter, more luminous Sun- like stars. Over the past decade, significant progress has been made by both space- and ground-based observatories to measure the likelihood of small planets to orbit in the habitable zones of M-dwarf stars. We now know that most M dwarfs are hosts to closely-packed planetary systems characterized by a paucity of Jupiter-mass planets and the presence of multiple rocky planets, with roughly a third of these rocky M-dwarf planets orbiting within the habitable zone, where they have the potential to support liquid water on their surfaces. Theoretical studies have also quantified the effect on climate and habitability of the interaction between the spectral energy distribution of M-dwarf stars and the atmospheres and surfaces of their planets. These and other recent results fill in knowledge gaps that existed at the time of the previous overview papers published nearly a decade ago by Tarter et al. -
Abstracts of Extreme Solar Systems 4 (Reykjavik, Iceland)
Abstracts of Extreme Solar Systems 4 (Reykjavik, Iceland) American Astronomical Society August, 2019 100 — New Discoveries scope (JWST), as well as other large ground-based and space-based telescopes coming online in the next 100.01 — Review of TESS’s First Year Survey and two decades. Future Plans The status of the TESS mission as it completes its first year of survey operations in July 2019 will bere- George Ricker1 viewed. The opportunities enabled by TESS’s unique 1 Kavli Institute, MIT (Cambridge, Massachusetts, United States) lunar-resonant orbit for an extended mission lasting more than a decade will also be presented. Successfully launched in April 2018, NASA’s Tran- siting Exoplanet Survey Satellite (TESS) is well on its way to discovering thousands of exoplanets in orbit 100.02 — The Gemini Planet Imager Exoplanet Sur- around the brightest stars in the sky. During its ini- vey: Giant Planet and Brown Dwarf Demographics tial two-year survey mission, TESS will monitor more from 10-100 AU than 200,000 bright stars in the solar neighborhood at Eric Nielsen1; Robert De Rosa1; Bruce Macintosh1; a two minute cadence for drops in brightness caused Jason Wang2; Jean-Baptiste Ruffio1; Eugene Chiang3; by planetary transits. This first-ever spaceborne all- Mark Marley4; Didier Saumon5; Dmitry Savransky6; sky transit survey is identifying planets ranging in Daniel Fabrycky7; Quinn Konopacky8; Jennifer size from Earth-sized to gas giants, orbiting a wide Patience9; Vanessa Bailey10 variety of host stars, from cool M dwarfs to hot O/B 1 KIPAC, Stanford University (Stanford, California, United States) giants. 2 Jet Propulsion Laboratory, California Institute of Technology TESS stars are typically 30–100 times brighter than (Pasadena, California, United States) those surveyed by the Kepler satellite; thus, TESS 3 Astronomy, California Institute of Technology (Pasadena, Califor- planets are proving far easier to characterize with nia, United States) follow-up observations than those from prior mis- 4 Astronomy, U.C. -
Generation of Earth's First-Order Biodiversity Pattern
ASTROBIOLOGY Volume 9, Number 1, 2009 © Mary Ann Liebert, Inc. DOI: 10.1089/ast.2008.0253 Review Generation of Earth’s First-Order Biodiversity Pattern Andrew Z. Krug,1 David Jablonski,1 James W. Valentine,2 and Kaustuv Roy3 Abstract The first-order biodiversity pattern on Earth today and at least as far back as the Paleozoic is the latitudinal di- versity gradient (LDG), a decrease in richness of species and higher taxa from the equator to the poles. LDGs are produced by geographic trends in origination, extinction, and dispersal over evolutionary timescales, so that analyses of static patterns will be insufficient to reveal underlying processes. The fossil record of marine bivalve genera, a model system for the analysis of biodiversity dynamics over large temporal and spatial scales, shows that an origination and range-expansion gradient plays a major role in generating the LDG. Peak orig- ination rates and peak diversities fall within the tropics, with range expansion out of the tropics the predomi- nant spatial dynamic thereafter. The origination-diversity link occurs even in a “contrarian” group whose di- versity peaks at midlatitudes, an exception proving the rule that spatial variations in origination are key to Ն latitudinal diversity patterns. Extinction rates are lower in polar latitudes ( 60°) than in temperate zones and thus cannot create the observed gradient alone. They may, however, help to explain why origination and im- migration are evidently damped in higher latitudes. We suggest that species require more resources in higher latitudes, for the seasonality of primary productivity increases by more than an order of magnitude from equa- torial to polar regions. -
Comparative Planetology and the Search for Life Beyond the Solar System
Beichman et al.: The Search for Life Beyond the Solar System 915 Comparative Planetology and the Search for Life Beyond the Solar System Charles A. Beichman California Institute of Technology Malcolm Fridlund European Space Agency Wesley A. Traub and Karl R. Stapelfeldt Jet Propulsion Laboratory Andreas Quirrenbach University of Leiden Sara Seager Carnegie Institute of Washington The study of planets beyond the solar system and the search for other habitable planets and life is just beginning. Groundbased (radial velocity and transits) and spacebased surveys (tran- sits and astrometry) will identify planets spanning a wide range of size and orbital location, from Earth-sized objects within 1 AU to giant planets beyond 5 AU, orbiting stars as near as a few parsec and as far as a kiloparsec. After this initial reconnaissance, the next generation of space observatories will directly detect photons from planets in the habitable zones of nearby stars. The synergistic combination of measurements of mass from astrometry and radial velocity, of radius and composition from transits, and the wealth of information from the direct detection of visible and mid-IR photons will create a rich field of comparative planetology. Information on protoplanetary and debris disks will complete our understanding of the evolution of habitable environments from the earliest stages of planet formation to the transport into the inner solar system of the volatiles necessary for life. The suite of missions necessary to carry out the search for nearby, habitable planets and life requires a “Great Observatories” program for planet finding (SIM PlanetQuest, Terrestrial Planet Finder-Coronagraph, and Terrestrial Planet Finder-Interfer- ometer/Darwin), analogous to the highly successful “Great Observatories Program” for astro- physics. -
DAVID SEPKOSKI Department of History University of Illinois, Champaign-Urbana Gregory Hall 301 810 S
DAVID SEPKOSKI Department of History University of Illinois, Champaign-Urbana Gregory Hall 301 810 S. Wright St. Urbana, IL 61801 [email protected] Updated 7/2020 ACADEMIC APPOINTMENTS 2018 - Thomas M. Siebel Chair in History of Science and Professor of History Affiliate Professor, School of Information University of Illinois, Urbana-Champaign 2012 - 2018 Max Planck Institute for the History of Science Senior Research Scholar, Department II 2006 - 2012 University of North Carolina Wilmington Associate Professor of History, 2010 - 2012 Assistant Professor of History, 2006 - 2010 2002 – 2006 Oberlin College Visiting Assistant Professor of History, 2004 - 2006 Mellon Postdoctoral Fellow in History, 2002 - 2004 EDUCATION 2002 University of Minnesota. Ph.D., Program in History of Science and Technology 1996 University of Chicago. A.M., Social Sciences 1994 Carleton College. B.A., History FELLOWSHIPS AND AWARDS 2020-21 John Simon Guggenheim Memorial Fellowship 2018-23 President’s Distinguished Faculty Hiring Program ($500,000 over 5 years for graduate student fellowships, research support, public programming and outreach), University of Illinois, Urbana-Champaign 2011 Visiting Fellow, Max Planck Institute for the History of Science, Department II, Berlin, Germany 2005-08 National Science Foundation STS Scholars Award. PI for grant funding “The Renaissance of Evolutionary Paleobiology, 1970-1985” Sepkoski 2 2007 Charles L. Cahill Award for Faculty Research and Development, UNC Wilmington 2006-07 FESR Investigator Fellow, UNC Wilmington 2005 Mead-Swing Fellow in the History of Science, Oberlin College 2004 Grant-in-Aid, Oberlin College, award for faculty research support 2000-01 Doctoral Dissertation Fellowship, University of Minnesota 1997-98 Graduate School Fellowship, University of Minnesota PUBLICATIONS Books 2020 Catastrophic Thinking: Extinction and the Value of Diversity Chicago: University of Chicago Press.