WorldWideScience

Sample records for extraordinarily earth-like world

  1. Giant Impacts on Earth-Like Worlds

    Science.gov (United States)

    Kohler, Susanna

    2016-05-01

    Earth has experienced a large number of impacts, from the cratering events that may have caused mass extinctions to the enormous impact believed to have formed the Moon. A new study examines whether our planets impact history is typical for Earth-like worlds.N-Body ChallengesTimeline placing the authors simulations in context of the history of our solar system (click for a closer look). [Quintana et al. 2016]The final stages of terrestrial planet formation are thought to be dominated by giant impacts of bodies in the protoplanetary disk. During this stage, protoplanets smash into one another and accrete, greatly influencing the growth, composition, and habitability of the final planets.There are two major challenges when simulating this N-body planet formation. The first is fragmentation: since computational time scales as N^2, simulating lots of bodies that split into many more bodies is very computationally intensive. For this reason, fragmentation is usually ignored; simulations instead assume perfect accretion during collisions.Total number of bodies remaining within the authors simulations over time, with fragmentation included (grey) and ignored (red). Both simulations result in the same final number of bodies, but the ones that include fragmentation take more time to reach that final number. [Quintana et al. 2016]The second challengeis that many-body systems are chaotic, which means its necessary to do a large number of simulations to make statistical statements about outcomes.Adding FragmentationA team of scientists led by Elisa Quintana (NASA NPP Senior Fellow at the Ames Research Center) has recently pushed at these challenges by modeling inner-planet formation using a code that does include fragmentation. The team ran 140 simulations with and 140 without the effects of fragmentation using similar initial conditions to understand how including fragmentation affects the outcome.Quintana and collaborators then used the fragmentation-inclusive simulations to

  2. Climate of an Earth-Like World with Changing Eccentricity

    Science.gov (United States)

    Kohler, Susanna

    2017-02-01

    Having a giant planet like Jupiter next door can really wreak havoc on your orbit! A new study examines what such a bad neighbor might mean for the long-term climate of an Earth-like planet.Influence of a Bad NeighborThe presence of a Jupiter-like giant planet in a nearby orbit can significantly affect how terrestrial planets evolve dynamically, causing elements like the planets orbital eccentricities and axial tilts to change over time. Earth is saved this inconvenience Jupiter isnt close enough to significantly influence us, and our large moon stabilizes our orbit against Jupiters tugs.Top panels: Authors simulationoutcomes for Case1, in which the planets eccentricity varies from 0 to 0.283 over 6500 years. Bottom panels: Outcomes for Case 2, in which the planets eccentricity varies from 0 to 0.066 over 4500 years. The highereccentricities reached in Case 1 causes the climate parameters to vary more widely. Click for a better look! [Way Georgakarakos 2017]Mars, on the other hand, isnt as lucky: its possible that Jupiters gravitational pull causes Marss axial tilt, for instance, to evolve through a range as large as 0 to 60 degrees on timescales of millions of years! Marss orbital eccentricity is similarly thought to vary due to Jupiters influence, and both of these factors play a major role in determining Marss climate.As exoplanet missions discover more planets many of which are Earth-like we must carefully consider which among these are most likely to be capable of sustaining life. If having a nearby neighbor like a Jupiter can tug an Earth-like world into an orbit with varying eccentricity, how does this affect the planets climate? Will the planet remain temperate? Or will it develop a runaway heating or cooling effect as it orbits, rendering it uninhabitable?Oceans and OrbitsTo examine these questions, two scientists have built the first ever 3D global climate model simulations of an Earth-like world using a fully coupled ocean (necessary for understanding

  3. Effects of Variable Eccentricity on the Climate of an Earth-like World

    Science.gov (United States)

    Way, M. J.; Georgakarakos, Nikolaos

    2017-01-01

    The Kepler era of exoplanetary discovery has presented the astronomical community with a cornucopia of planetary systems that are very different from the one that we inhabit. It has long been known that Jupiter plays a major role in the orbital parameters of Mars and its climate, but there is also a long-standing belief that Jupiter would play a similar role for Earth if not for the Moon. Using a three-dimensional general circulation model (3D GCM) with a fully coupled ocean, we simulate what would happen to the climate of an Earth-like world if Mars did not exist, but a Jupiter-like planet was much closer to Earth’s orbit. We investigate two scenarios that involve the evolution of the Earth-like planet’s orbital eccentricity from 0 to 0.283 over 6500 years, and from 0 to 0.066 on a timescale of 4500 years. In both cases we discover that they would maintain relatively temperate climates over the timescales simulated. More Earth-like planets in multi-planet systems will be discovered as we continue to survey the skies and the results herein show that the proximity of large gas giant planets may play an important role in the habitability of these worlds. These are the first such 3D GCM simulations using a fully coupled ocean with a planetary orbit that evolves over time due to the presence of a giant planet.

  4. Effects of Variable Eccentricity on the Climate of an Earth-Like World

    Science.gov (United States)

    Way, M. J.; Georgakarakos, Nikolaos

    2017-01-01

    The Kepler era of exoplanetary discovery has presented the Astronomical community with a cornucopia of planetary systems very different from the one which we inhabit. It has long been known that Jupiter plays a major role in the orbital parameters of Mars and its climate, but there is also a long-standing belief that Jupiter would play a similar role for Earth if not for its large moon. Using a three dimensional general circulation model (3-D GCM) with a fully-coupled ocean we simulate what would happen to the climate of an Earth-like world if Mars did not exist, but a Jupiter-like planet was much closer to Earths orbit. We investigate two scenarios that involve evolution of the Earth-like planets orbital eccentricity from 0 to 0.066 on a time scale of 4500 years, and from 0 to 0.283 over 6500 years. We discover that during most of the 6500 year scenario the planet would experience a moist greenhouse effect when near periastron. This could have implications for the ability of such a world to retain an ocean on time scales of 109 years. More Earth-like planets in multi-planet systems will be discovered as we continue to survey the skies and the results herein show that the proximity of large gas giant planets may play an important role in the habitabilty of these worlds. These are the first such 3-D GCM simulations using a fully-coupled ocean with a planetary orbit that evolves over time due to the presence of a giant planet.

  5. Effects of variable eccentricity on the climate of an Earth-like world

    CERN Document Server

    Way, Michael J

    2016-01-01

    The Kepler era of exoplanetary discovery has presented the Astronomical community with a cornucopia of planetary systems very different from the one which we inhabit. It has long been known that Jupiter plays a major role in the orbital parameters of Mars and it's climate, but there is also a long-standing belief that Jupiter would play a similar role for Earth if not for its large moon. Using a three dimensional general circulation model (3-D GCM) with a fully-coupled ocean we simulate what would happen to the climate of an Earth-like world if Mars did not exist, but a Jupiter-like planet was much closer to Earth's orbit. We investigate two scenarios that involve evolution of the Earth-like planet's orbital eccentricity from 0--0.066 on a time scale of 4500 years, and from 0--0.283 over 6500 years. We discover that during most of the 6500 year scenario the planet would experience a moist greenhouse effect when near periastron. This could have implications for the ability of such a world to retain an ocean on...

  6. EXPRES: A Next Generation RV Spectrograph in the Search for Earth-like Worlds

    CERN Document Server

    Jurgenson, C; McCracken, T; Sawyer, D; Szymkowiak, A; Davis, A B; Muller, G; Santoro, F

    2016-01-01

    The EXtreme PREcision Spectrograph (EXPRES) is an optical fiber fed echelle instrument being designed and built at the Yale Exoplanet Laboratory to be installed on the 4.3-meter Discovery Channel Telescope operated by Lowell Observatory. The primary science driver for EXPRES is to detect Earth-like worlds around Sun-like stars. With this in mind, we are designing the spectrograph to have an instrumental precision of 15 cm/s so that the on-sky measurement precision (that includes modeling for RV noise from the star) can reach to better than 30 cm/s. This goal places challenging requirements on every aspect of the instrument development, including optomechanical design, environmental control, image stabilization, wavelength calibration, and data analysis. In this paper we describe our error budget, and instrument optomechanical design.

  7. Earth-like Habitats in Planetary Systems

    CERN Document Server

    Fritz, Jörg; Kührt, Ekkehard; Morbidelli, Alessandro; Tornow, Carmen; Wünnemann, Kai; Fernandes, Vera A; Grenfell, Lee J; Rauer, Heike; Wagner, Roland; Werner, Stephanie C

    2014-01-01

    Understanding the concept of habitability is related to an evolutionary knowledge of the particular planet-in-question. Additional indications so-called "systemic aspects" of the planetary system as a whole governs a particular planet's claim on habitability. Here we focus on such systemic aspects and discuss their relevance to the formation of an 'Earth-like' habitable planet. We summarize our results obtained by lunar sample work and numerical models within the framework of the Research Alliance "Planetary Evolution and Life". We consider various scenarios which simulate the dynamical evolution of the Solar System and discuss the likelihood of forming an Earth-like world orbiting another star. Our model approach is constrained by observations of the modern Solar System and the knowledge of its history. Results suggest that the long-term presence of terrestrial planets is jeopardized due to gravitational interactions if giant planets are present. But habitability of inner rocky planets may be supported in th...

  8. Giant Impacts on Earth-like Worlds

    CERN Document Server

    Quintana, Elisa V; Borucki, William; Rowe, Jason F; Chambers, John E

    2015-01-01

    The late stages of terrestrial planet formation are dominated by giant impacts that collectively influence the growth, dynamical stability, composition and habitability of any planets that form. Hitherto, numerical models designed to explore these late stage collisions have been limited in two major ways. First, nearly all N-body models have assumed that two-body collisions lead to perfect accretion. Second, many of these studies lack the large number of realizations needed to account for the chaotic nature of these N-body systems. In this article we perform hundreds of simulations of late stage terrestrial planet formation using an N-body algorithm that includes fragmentation and hit-and-run collisions. We performed 140 simulations of planet accretion around a Sun-like star with Jupiter and Saturn analogs with and without this new collision model. We find that when fragmentation is included, the final planets formed are similar to those formed in the perfect-accretion model in terms of mass and number, howev...

  9. Evolution of Earth Like Planets

    Science.gov (United States)

    Monroy-Rodríguez, M. A.; Vega, K. M.

    2017-07-01

    In order to study and explain the evolution of our own planet we have done a review of works related to the evolution of Earth-like planets. From the stage of proto-planet to the loss of its atmosphere. The planetary formation from the gas and dust of the proto-planetary disk, considering the accretion by the process of migration, implies that the material on the proto-planet is very mixed. The newborn planet is hot and compact, it begins its process of stratification by gravity separation forming a super dense nucleus, an intermediate layer of convective mantle and an upper mantle that is less dense, with material that emerges from zones at very high pressure The surface with low pressure, in this process the planet expands and cools. This process also releases gas to the surface, forming the atmosphere, with the gas gravitationally bounded. The most important thing for the life of the planet is the layer of convective mantle, which produces the magnetic field, when it stops the magnetic field disappears, as well as the rings of van allen and the solar wind evaporates the atmosphere, accelerating the evolution and cooling of the planet. In a natural cycle of cataclysms and mass extinctions, the solar system crosses the galactic disk every 30 million years or so, the increase in the meteorite fall triggers the volcanic activity and the increase in the release of CO2 into the atmosphere reaching critical levels (4000 billion tons) leads us to an extinction by overheating that last 100 000 years, the time it takes CO2 to sediment to the ocean floor. Human activity will lead us to reach critical levels of CO2 in approximately 300 years.

  10. Transits of Earth-Like Planets

    CERN Document Server

    Kaltenegger, L

    2009-01-01

    Transmission spectroscopy of Earth-like exoplanets is a potential tool for habitability screening. Transiting planets are present-day "Rosetta Stones" for understanding extrasolar planets because they offer the possibility to characterize giant planet atmospheres and should provide an access to biomarkers in the atmospheres of Earth-like exoplanets, once they are detected. Using the Earth itself as a proxy we show the potential and limits of the transiting technique to detect biomarkers on an Earth-analog exoplanet in transit. We quantify the Earths cross section as a function of wavelength, and show the effect of each atmospheric species, aerosol, and Rayleigh scattering. Clouds do not significantly affect this picture because the opacity of the lower atmosphere from aerosol and Rayleigh losses dominates over cloud losses. We calculate the optimum signal-to-noise ratio for spectral features in the primary eclipse spectrum of an Earth-like exoplanet around a Sun-like star and also M stars, for a 6.5-m telesco...

  11. Atmospheric tides in Earth-like planets

    CERN Document Server

    Auclair-Desrotour, Pierre; Mathis, Stéphane

    2016-01-01

    Atmospheric tides can strongly affect the rotational dynamics of planets. In the family of Earth-like planets, such as Venus, this physical mechanism coupled with solid tides makes the angular velocity evolve over long timescales and determines the equilibrium configurations of their spin. Contrary to the solid core, the atmosphere is submitted to both tidal gravitational potential and insolation flux coming from the star. The complex response of the gas is intrinsically linked to its physical properties. This dependence has to be characterized and quantified to study the large variety of extrasolar planetary systems. We develop a theoretical global model where radiative losses, which are predominant in slowly rotating atmospheres, are taken into account. We analytically compute the tidal perturbation of pressure, density, temperature and velocity field from which we deduce the expressions of atmospheric Love numbers and tidal torque exerted by the star. The dynamics of atmospheric tides depends on the freque...

  12. Lightning chemistry on Earth-like exoplanets

    Science.gov (United States)

    Ardaseva, Aleksandra; Rimmer, Paul B.; Waldmann, Ingo; Rocchetto, Marco; Yurchenko, Sergey N.; Helling, Christiane; Tennyson, Jonathan

    2017-09-01

    We present a model for lightning shock-induced chemistry that can be applied to atmospheres of arbitrary H/C/N/O chemistry, hence for extrasolar planets and brown dwarfs. The model couples hydrodynamics and the STAND2015 kinetic gas-phase chemistry. For an exoplanet analogue to the contemporary Earth, our model predicts NO and NO2 yields in agreement with observation. We predict height-dependent mixing ratios during a storm soon after a lightning shock of NO ≈10-3 at 40 km and NO2 ≈10-4 below 40 km, with O3 reduced to trace quantities (≪10-10). For an Earth-like exoplanet with a CO2/N2 dominated atmosphere and with an extremely intense lightning storm over its entire surface, we predict significant changes in the amount of NO, NO2, O3, H2O, H2 and predict a significant abundance of C2N. We find that, for the Early Earth, O2 is formed in large quantities by lightning but is rapidly processed by the photochemistry, consistent with previous work on lightning. The chemical effect of persistent global lightning storms are predicted to be significant, primarily due to NO2, with the largest spectral features present at ∼3.4 and ∼6.2 μm. The features within the transmission spectrum are on the order of 1 ppm and therefore are not likely detectable with the James Webb Space Telescope. Depending on its spectral properties, C2N could be a key tracer for lightning on Earth-like exoplanets with a N2/CO2 bulk atmosphere, unless destroyed by yet unknown chemical reactions.

  13. Atmospheric tides in Earth-like planets

    Science.gov (United States)

    Auclair-Desrotour, P.; Laskar, J.; Mathis, S.

    2017-07-01

    Context. Atmospheric tides can strongly affect the rotational dynamics of planets. In the family of Earth-like planets, which includes Venus, this physical mechanism coupled with solid tides makes the angular velocity evolve over long timescales and determines the equilibrium configurations of their spin. Aims: Unlike the solid core, the atmosphere of a planet is subject to both tidal gravitational potential and insolation flux coming from the star. The complex response of the gas is intrinsically linked to its physical properties. This dependence has to be characterized and quantified for application to the wide variety of extrasolar planetary systems. Methods: We develop a theoretical global model where radiative losses, which are predominant in slowly rotating atmospheres, are taken into account. We analytically compute the perturbation of pressure, density, temperature, and velocity field caused by a thermogravitational tidal perturbation. From these quantities, we deduce the expressions of atmospheric Love numbers and tidal torque exerted on the fluid shell by the star. The equations are written for the general case of a thick envelope and the simplified one of a thin isothermal atmosphere. Results: The dynamics of atmospheric tides depends on the frequency regime of the tidal perturbation: the thermal regime near synchronization and the dynamical regime characterizing fast-rotating planets. Gravitational and thermal perturbations imply different responses of the fluid, i.e. gravitational tides and thermal tides, which are clearly identified. The dependence of the torque on the tidal frequency is quantified using the analytic expressions of the model for Earth-like and Venus-like exoplanets and is in good agreement with the results given by global climate models (GCM) simulations.Introducing dissipative processes such as radiation regularizes the tidal response of the atmosphere, otherwise it is singular at synchronization. Conclusions: We demonstrate the

  14. A Laboratory Demonstration of the Capability to Image an Earth-like Extrasolar Planet

    Science.gov (United States)

    Trauger, John T.; Wesley, A. Traub

    2007-01-01

    The detection and characterization of an Earth-like planet orbiting a nearby star requires a telescope with an extraordinarily large contrast at small angular separations. At visible wavelengths, an Earth-like planet would be 1 times 10-10 times fainter than the star at angular separations of typically 0.1 arcsecond or less. There are several proposed space telescope systems that could, in principle, achieve this. Here we report a laboratory experiment that reaches these limits. We have suppressed the diffracted and scattered light near a star-like source to a level of 6 times 10-10 times the peak intensity in individual coronagraph images. In a series of such images, together with simple image processing, we have effectively reduced this to a residual noise level of about 0.1 times 10-10. This demonstrates that a coronagraphic telescope in space could detect and spectroscopically characterize nearby exoplanetary systems, with the sensitivity to image an 'Earth-twin' orbiting a nearby star.

  15. The Search for Extrasolar Earth-like planets

    CERN Document Server

    Seager, S

    2003-01-01

    The search for extrasolar Earth-like planets is underway. Over 100 extrasolar giant planets are known to orbit nearby sun-like stars, including several in multiple-planet systems. These planetary systems are stepping stones for the search for Earth-like planets; the technology development, observational strategies, and science results can all be applied to Earth-like planets. Stars much less massive than the sun the most common stars in our Galaxy are being monitored for the gravitational influence of Earth-like planets. Although Earth-like planets orbiting sun-like stars are much more difficult to detect, space missions are being built to detect them indirectly due to their effects on the parent star and to quantify fundamental factors such as terrestrial planet frequency, size distribution, and mass distribution. Extremely ambitious space programs are being developed to directly detect Earth-like planets orbiting sun-like stars, and must tackle the immense technological challenge of blocking out the light o...

  16. Un-Earth-like interiors of the Earth-like planets

    Science.gov (United States)

    Shim, S. H. D.; Nisr, C.; Pagano, M.; Chen, H.; Ko, B.; Noble, S.; Leinenweber, K. D.; Young, P.; Desch, S. J.

    2015-12-01

    A number of exoplanets have been described as "Earth-like" planets (or even exo-earths) based on the mass-radius relations. Yet, significant variations have been documented in elemental abundances of planet-hosting stars, which will result in very different structures and processes in the interiors of rocky exoplanets. Recent data suggest that the Mg/Si ratio can be as small as less than 1 and as large as more than 2, opening the possibilities for the upper mantles to be dominated by pyroxene and olivine, respectively, and the lower mantles to be dominated by bridgmanite and ferropericlase, respectively. The changes in mineralogy will alter key properties, such as discontinuity structures (and therefore scale of mantle mixing), viscosity, and volatiles storage, of the mantle. Partial melting of such mantles would result in different compositions of the crusts, affecting the tectonics. However, the prediction should be made carefully because oxygen fugacity and contents of volatiles can change the mineralogy even for the same bulk composition. In extremely reducing proto-planetary disks, carbides will form instead of oxides and silicates, and become main constituents of planets in the system. Because carbides have high thermal conductivity and low thermal expansivity, internal heat transport of such planets may be dominated by conduction and mantle mixing would be much more limited than that of the Earth. However, the behaviors and properties of carbides need to be understood better at high pressure and high temperature. Some rocky exoplanets may have very thick layers of water and other icy materials. Interactions between ice (or fluid) and rock at extreme conditions would be the key to understand dynamics and habitability of such exoplanets.

  17. Uncovering the Chemistry of Earth-like Planets

    Science.gov (United States)

    Zeng, L.; Jacobsen, S. B.; Sasselov, D. D.

    2015-12-01

    We propose to use the evidence from our solar system to understand exoplanets, and in particular, to predict their surface chemistry and thereby the possibility of life. An Earth-like planet, born from the same nebula as its host star, is composed primarily of silicate rocks and an iron-nickel metal core, and depleted in volatile content in a systematic manner. The more volatile (easier to vaporize or dissociate into gas form) an element is in an Earth-like planet, the more depleted the element is compared to its host star. After depletion, an Earth-like planet would go through the process of core formation due to heat from radioactive decay and collisions. Core formation depletes a planet's rocky mantle of siderophile (iron-loving) elements, in addition to the volatile depletion. After that, Earth-like planets likely accrete some volatile-rich materials, called "late veneer". The late veneer could be essential to the origins of life on Earth and Earth-like planets, as it also delivers the volatiles such as nitrogen, sulfur, carbon and water to the planet's surface, which are crucial for life to occur. Here we build an integrative model of Earth-like planets from the bottom up. Thus the chemical compositions of Earth-like planets could be inferred from their mass-radius relations and their host stars' elemental abundances, and the origins of volatile contents (especially water) on their surfaces could be understood, and thereby shed light on the origins of life on them. This elemental abundance model could be applied to other rocky exoplanets in exoplanet systems.

  18. Earth-Like Exoplanets: The Science of NASA's Navigator Program

    Science.gov (United States)

    Lawson, Peter R. (Editor); Traub, Wesley A. (Editor)

    2006-01-01

    This book outlines the exoplanet science content of NASA's Navigator Program, and it identifies the exoplanet research priorities. The goal of Navigator Program missions is to detect and characterize Earth-like planets in the habitable zone of nearby stars and to search for signs of life on those planets.

  19. Kepler Mission to Detect Earth-like Planets

    Science.gov (United States)

    Kondo, Yoji

    2002-01-01

    Kepler Mission to detect Earth-like planets in our Milky Way galaxy was approved by NASA in December 2001 for a 4-5 year mission. The launch is planned in about 5 years. The Kepler observatory will be placed in an Earth-trailing orbit. The unique feature of the Kepler Mission is its ability to detect Earth-like planets orbiting around solar-type stars at a distance similar to that of Earth (from our Sun); such an orbit could provide an environment suitable for supporting life as we know it. The Kepler observatory accomplishes this feat by looking for the transits of planetary object in front of their suns; Kepler has a photometric precision of 10E-5 (0.00001) to achieve such detections. Other ongoing planetary detection programs (based mostly on a technique that looks for the shifting of spectral lines of the primary star due to its planetary companions' motions around it) have detected massive planets (with masses in the range of Jupiter); such massive planets are not considered suitable for supporting life. If our current theories for the formation of planetary systems are valid, we expect to detect about 50 Earth-like planets during Kepler's 4-year mission (assuming a random distribution of the planetary orbital inclinations with respect to the line of sight from Kepler). The number of detection will increase about 640 planets if the planets to be detected are Jupiter-sized.

  20. Searching for Earth-like planets in this solar system and beyond

    Science.gov (United States)

    Stofan, E. R.

    2014-12-01

    Earth sits in a narrow habitable zone, and its future habitability depends on the actions of those who inhabit the planet today. Earth's complex climate reflects interactions between its interior, surface, oceans, biosphere, atmosphere and its star - our sun. Studying the climates of other planets around our sun - Mars, Venus and Titan - can help us better understand the processes that control climate here on Earth. These three bodies provide compelling targets for future study as we explore beyond our solar system to find Earth-like worlds around other stars.

  1. Spectral fingerprints of Earth-like planets around FGK stars.

    Science.gov (United States)

    Rugheimer, Sarah; Kaltenegger, Lisa; Zsom, Andras; Segura, Antígona; Sasselov, Dimitar

    2013-03-01

    We present model atmospheres for an Earth-like planet orbiting the entire grid of main sequence FGK stars with effective temperatures ranging from Teff=4250 K to Teff=7000 K in 250 K intervals. We have modeled the remotely detectable spectra of Earth-like planets for clear and cloudy atmospheres at the 1 AU equivalent distance from the VIS to IR (0.4 to 20 μm) to compare detectability of features in different wavelength ranges in accordance with the James Webb Space Telescope and future design concepts to characterize exo-Earths. We have also explored the effect of the stellar UV levels as well as spectral energy distribution on a terrestrial atmosphere, concentrating on detectable atmospheric features that indicate habitability on Earth, namely, H2O, O3, CH4, N2O, and CH3Cl. The increase in UV dominates changes of O3, OH, CH4, N2O, and CH3Cl, whereas the increase in stellar temperature dominates changes in H2O. The overall effect as stellar effective temperatures and corresponding UV increase is a lower surface temperature of the planet due to a bigger part of the stellar flux being reflected at short wavelengths, as well as increased photolysis. Earth-like atmosphere models show more O3 and OH but less stratospheric CH4, N2O, CH3Cl, and tropospheric H2O (but more stratospheric H2O) with increasing effective temperature of main sequence stars. The corresponding detectable spectral features, on the other hand, show different detectability depending on the wavelength observed. We concentrate on directly imaged planets here as a framework to interpret future light curves, direct imaging, and secondary eclipse measurements of atmospheres of terrestrial planets in the habitable zone at varying orbital positions.

  2. An Earth-Like Planet in GJ 832 System

    CERN Document Server

    Satyal, S; Musielak, Z E

    2016-01-01

    Stability of planetary orbits around GJ 832 star system, which contains inner (GJ 832c) and outer (GJ 832b) planets, is investigated numerically and the detailed phase-space analysis are performed. The stability of the system is de?ned in terms of its lifetime, which is its survival time during the orbital integration period, and the maximum eccentricity, emax attained by the orbits during the evolution processes. A special emphasis is given to the existence of stable orbits for an Earth-like planet that is injected between the inner and outer planets. Thus, numerical simulations are performed for three and four bodies in elliptical orbits (or circular for special cases), and a large number of initial conditions that covers the whole phase-space of the existing bodies are used. The results presented in the phase-space maps for GJ 832c indicates the least deviation of the eccentricity from its nominal value, which is then used to determine its inclination regime. Also, the Earth-like planet displays stable orb...

  3. Spectral Fingerprints of Earth-like Planets Around FGK Stars

    CERN Document Server

    Rugheimer, Sarah; Zsom, Andras; Segura, Antígona; Sasselov, Dimitar

    2012-01-01

    We present model atmospheres for an Earth-like planet orbiting the entire grid of main sequence FGK stars with effective temperatures ranging from Teff = 4250K to Teff = 7000K in 250K intervals. We model the remotely detectable spectra of Earth-like planets for clear and cloudy atmospheres at the 1AU equivalent distance from the VIS to IR (0.4 {\\mu}m - 20 {\\mu}m) to compare detectability of features in different wavelength ranges in accordance with JWST and future design concepts to characterize exo-Earths. We also explore the effect of the stellar UV levels as well as spectral energy distribution on a terrestrial atmosphere concentrating on detectable atmospheric features that indicate habitability on Earth, namely: H2O, O3, CH4, N2O and CH3Cl. The increase in UV dominates changes of O3, OH, CH4, N2O and CH3Cl whereas the increase in stellar temperature dominates changes in H2O. The overall effect as stellar effective temperatures and corresponding UV increase, is a lower surface temperature of the planet du...

  4. Climate Stability of Habitable Earth-like Planets

    CERN Document Server

    Menou, Kristen

    2014-01-01

    The carbon-silicate cycle regulates the atmospheric $CO_2$ content of terrestrial planets on geological timescales through a balance between the rates of $CO_2$ volcanic outgassing and planetary intake from rock weathering. It is thought to act as an efficient climatic thermostat on Earth and, by extension, on other habitable planets. If, however, the weathering rate increases with the atmospheric $CO_2$ content, as expected on planets lacking land vascular plants, the carbon-silicate cycle feedback can become severely limited. Here we show that Earth-like planets receiving less sunlight than current Earth may no longer possess a stable warm climate but instead repeatedly cycle between unstable glaciated and deglaciated climatic states. This has implications for the search for life on exoplanets in the habitable zone of nearby stars.

  5. Climate stability of habitable Earth-like planets

    Science.gov (United States)

    Menou, Kristen

    2015-11-01

    The carbon-silicate cycle regulates the atmospheric CO2 content of terrestrial planets on geological timescales through a balance between the rates of CO2 volcanic outgassing and planetary intake from rock weathering. It is thought to act as an efficient climatic thermostat on Earth and, by extension, on other habitable planets. If, however, the weathering rate increases with the atmospheric CO2 content, as expected on planets lacking land vascular plants, the carbon-silicate cycle feedback can become severely limited. Here we show that Earth-like planets receiving less sunlight than current Earth may no longer possess a stable warm climate but instead repeatedly cycle between unstable glaciated and deglaciated climatic states. This has implications for the search for life on exoplanets in the habitable zone of nearby stars.

  6. Climate variations on Earth-like circumbinary planets

    Science.gov (United States)

    Popp, Max; Eggl, Siegfried

    2017-04-01

    The discovery of planets orbiting double stars at close distances has sparked increasing scientific interest in determining whether Earth-analogues can remain habitable in such environments and how their atmospheric dynamics is influenced by the rapidly changing insolation. In this work we present results of the first three-dimensional numerical experiments of a water-rich planet orbiting a double star. We find that the periodic forcing of the atmosphere has a noticeable impact on the planet's climate. Signatures of the forcing frequencies related to the planet's as well as to the binary's orbital periods are present in a variety of climate indicators such as temperature and precipitation, making the interpretation of potential observables challenging. However, for Earth-like greenhouse gas concentrations, the variable forcing does not change the range of insolation values allowing for habitable climates substantially.

  7. Space vehicle with artificial gravity and earth-like environment

    Science.gov (United States)

    Gray, V. H. (Inventor)

    1973-01-01

    A space vehicle adapted to provide an artificial gravity and earthlike atmospheric environment for occupants is disclosed. The vehicle comprises a cylindrically shaped, hollow pressure-tight body, one end of which is tapered from the largest diameter of the body, the other end is flat and transparent to sunlight. The vehicle is provided with thrust means which rotates the body about its longitudinal axis, generating an artificial gravity effect upon the interior walls of the body due to centrifugal forces. The walls of the tapered end of the body are maintained at a temperature below the dew point of water vapor in the body and lower than the temperature near the transparent end of the body. The controlled environment and sunlight permits an earth like environment to be maintained wherein the CO2/O2 is balanced, and food for the travelers is supplied through a natural system of plant life grown on spacecraft walls where soil is located.

  8. Atmospheric dynamics of Earth-like tidally locked aquaplanets

    CERN Document Server

    Merlis, Timothy M

    2010-01-01

    We present simulations of atmospheres of Earth-like aquaplanets that are tidally locked to their star, that is, planets whose orbital period is equal to the rotation period about their spin axis, so that one side always faces the star and the other side is always dark. As extreme cases illustrating the effects of slow and rapid rotation, we consider planets with rotation periods equal to one current Earth year and one current Earth day. The dynamics responsible for the surface climate (e.g., winds, temperature, precipitation) and the general circulation of the atmosphere are discussed in light of existing theories of atmospheric circulations. For example, as expected from the increasing importance of Coriolis accelerations relative to inertial accelerations as the rotation rate increases, the winds are approximately isotropic and divergent at leading order in the slowly rotating atmosphere but are predominantly zonal and rotational in the rapidly rotating atmosphere. Free-atmospheric horizontal temperature va...

  9. Climate variations on Earth-like circumbinary planets.

    Science.gov (United States)

    Popp, Max; Eggl, Siegfried

    2017-04-06

    The discovery of planets orbiting double stars at close distances has sparked increasing scientific interest in determining whether Earth-analogues can remain habitable in such environments and how their atmospheric dynamics is influenced by the rapidly changing insolation. In this work we present results of the first three-dimensional numerical experiments of a water-rich planet orbiting a double star. We find that the periodic forcing of the atmosphere has a noticeable impact on the planet's climate. Signatures of the forcing frequencies related to the planet's as well as to the binary's orbital periods are present in a variety of climate indicators such as temperature and precipitation, making the interpretation of potential observables challenging. However, for Earth-like greenhouse gas concentrations, the variable forcing does not change the range of insolation values allowing for habitable climates substantially.

  10. Mantle convection and plate tectonics on Earth-like exoplanets

    Science.gov (United States)

    Sotin, C.; Schubert, G.

    2009-12-01

    The likelihood of plate tectonics on exoplanets larger than Earth can be assessed using either scaling laws or numerical models describing mantle thermal convection. We investigate the parameters which control the ratio of convective driving forces to lithosphere resisting forces. Two papers, Valencia et al. (AstroPhys. J., 670, L45-L48, 2007) and O’Neill and Lenardic (Geophys. Res. Lett., 34, L19204, 2007), came to opposite conclusions based on scaling laws and numerical calculations, respectively. The different assumptions and parameters used in each study are compared. The definition of thermal boundary layer and lithosphere and the use of their characteristics in the scaling laws are clarified. We show that Valencia et al. (2007) overestimate the ratio of driving forces to resistive forces because they infer too large values for both the thickness of the thermal boundary layer and the length of the plate and too small a value for the yield strength. We show that this ratio is so weakly dependent on the size of an Earth-like planet that other parameters such as presence of water, heating per unit mass, upper mantle thickness, etc., may actually determine the occurrence or not of plate tectonics. The numerical calculations of O’Neill and Lenardic (2007) show the importance of 2D simulations for determining the values of the velocity below the lithosphere, the convective stresses, and the plate dimensions. It demonstrates the need for 3D spherical numerical simulations. Their conclusion that super-Earths would not have plate tectonics depends on a number of assumptions including the constancy of heat-flux as a function of planetary size. We present a 3D spherical scaling including the increase of heat flux with the size of a planet showing that larger Earth-like planets would be marginally in the mobile lid convection regime reinforcing our caution that other factors may tip the balance. The present study points out the importance of the distance between

  11. Extrasolar Giant Planet in Earth-like Orbit

    Science.gov (United States)

    1999-07-01

    companion . iota Hor b has an orbital period of 320 days. From this period, the known mass of the central star (1.03 solar masses) and the amplitude of the velocity changes, a mass of at least 2.26 times that of planet Jupiter is deduced for the planet. It revolves around the host star in a somewhat elongated orbit (the eccentricity is 0.16). If it were located in our own solar system, this orbit would stretch from just outside the orbit of Venus (at 117 million km or 0.78 Astronomical Units from the Sun) to just outside the orbit of the Earth (the point farthest from the Sun, at 162 million km or 1.08 Astronomical Units) The new giant planet is thus moving in an orbit not unlike that of the Earth. In fact, of all the planets discovered so far, the orbit of iota Hor b is the most Earth-like. Also, with a spectral type of G0 V , its host star is quite similar to the Sun (G2 V). iota Hor b is, however, at least 720 times more massive than the Earth and it is probably more similar to planet Jupiter in our own solar system. While the radial velocity technique described above only determines a minimum value for the planet's mass, an analysis of the velocity with which the star turns around its own axis suggests that the true mass of iota Hor b is unlikely to be much higher. A difficult case Natural phenomena with periods near one solar year always present a particular challenge to astronomers. This is one of the reasons why it has been necessary to observe the iota Hor system for such a long time to be absolutely sure about the present result. First, special care must be taken to verify that the radial velocity variations found in the data are not an artefact of the Earth's movement around the Sun. In any case, the effect of this movement on the measurements must be accurately accounted for; it reaches about ± 30 km/sec over one year, i.e. much larger than the effect of the new planet. In the present case of iota Hor , this was thoroughly tested and any residual influence of

  12. Modeling the surface temperature of Earth-like planets

    CERN Document Server

    Vladilo, G; Murante, G; Filippi, L; Provenzale, A

    2015-01-01

    We introduce a novel Earth-like planet surface temperature model (ESTM) for habitability studies based on the spatial-temporal distribution of planetary surface temperatures. The ESTM adopts a surface Energy Balance Model complemented by: radiative-convective atmospheric column calculations, a set of physically-based parameterizations of meridional transport, and descriptions of surface and cloud properties more refined than in standard EBMs. The parameterization is valid for rotating terrestrial planets with shallow atmospheres and moderate values of axis obliquity (epsilon >= 45^o). Comparison with a 3D model of atmospheric dynamics from the literature shows that the equator-to-pole temperature differences predicted by the two models agree within ~5K when the rotation rate, insolation, surface pressure and planet radius are varied in the intervals 0.5 <= Omega/Omega_o <= 2, 0.75 <= S/S_o <= 1.25, 0.3 <= p/(1 bar) <= 10, and 0.5 <= R/R_o <= 2, respectively. The ESTM has an extremely l...

  13. Biosignatures from Earth-Like Planets Around M Dwarfs

    CERN Document Server

    Segura, A; Meadows, V; Cohen, M; Scalo, J; Crisp, D; Butler, R A H; Tinetti, G; Segura, Antigona; Kasting, James F.; Meadows, Victoria; Cohen, Martin; Scalo, John; Crisp, David; Butler, Rebecca A.H.; Tinetti, Giovana

    2005-01-01

    Coupled one-dimensional photochemical-climate calculations have been performed for hypothetical Earth-like planets around M dwarfs. Visible, near-infrared and thermal-infrared synthetic spectra of these planets were generated to determine which biosignature gases might be observed by a future, space-based telescope. Our star sample included two observed active M dwarfs, AD Leo and GJ 643, and three quiescent model stars. The spectral distribution of these stars in the ultraviolet generates a different photochemistry on these planets. As a result, the biogenic gases CH4, N2O, and CH3Cl have substantially longer lifetimes and higher mixing ratios than on Earth, making them potentially observable by space-based telescopes. On the active M-star planets, an ozone layer similar to Earth's was developed that resulted in a spectroscopic signature comparable to the terrestrial one. The simultaneous detection of O2 (or O3) and a reduced gas in a planet's atmosphere has been suggested as strong evidence for life. Planet...

  14. The Maximal Runaway Temperature of Earth-like Planets

    CERN Document Server

    Shaviv, Nir J; Wehrse, Rainer

    2012-01-01

    We generalize the problem of the semi-gray model to cases in which a non-negligible fraction of the stellar radiation falls on the long-wavelength range, and/or that the planetary long-wavelength emission penetrates into the transparent short wavelength domain of the absorption. Second, applying the most general assumptions and independently of any particular properties of an absorber, we show that the greenhouse effect saturates and any Earth-like planet has a maximal temperature which depends on the type of and distance to its main-sequence star, its albedo and the primary atmospheric components which determine the cutoff frequency below which the atmosphere is optically thick. For example, a hypothetical convection-less planet similar to Venus, that is optically thin in the visible, could have at most a surface temperature of 1200-1300K irrespective of the nature of the greenhouse gas. We show that two primary mechanisms are responsible for the saturation of the runaway greenhouse effect, depending on the ...

  15. Characterizing Earth-like Planets with Terrestrial Planet Finder

    CERN Document Server

    Seager, S; Turner, E L

    2002-01-01

    For the first time in human history the possibility of detecting and studying Earth-like planets is on the horizon. Terrestrial Planet Finder (TPF), with a launch date in the 2015 timeframe, is being planned by NASA to find and characterize planets in the habitable zones of nearby stars. The mission Darwin from ESA has similar goals. The motivation for both of these space missions is the detection and spectroscopic characterization of extrasolar terrestrial planet atmospheres. Of special interest are atmospheric biomarkers--such as O2, O3, H2O, CO and CH4--which are either indicative of life as we know it, essential to life, or can provide clues to a planet's habitability. A mission capable of measuring these spectral features would also obtain sufficient signal-to-noise to characterize other terrestrial planet properties. For example, physical characteristics such as temperature and planetary radius can be constrained from low- resolution spectra. In addition, planet characteristics such as weather, rotation...

  16. Biosignatures from Earth-like planets around M dwarfs.

    Science.gov (United States)

    Segura, Antígona; Kasting, James F; Meadows, Victoria; Cohen, Martin; Scalo, John; Crisp, David; Butler, Rebecca A H; Tinetti, Giovanna

    2005-12-01

    Coupled one-dimensional photochemical-climate calculations have been performed for hypothetical Earth-like planets around M dwarfs. Visible/near-infrared and thermal-infrared synthetic spectra of these planets were generated to determine which biosignature gases might be observed by a future, space-based telescope. Our star sample included two observed active M dwarfs-AD Leo and GJ 643-and three quiescent model stars. The spectral distribution of these stars in the ultraviolet generates a different photochemistry on these planets. As a result, the biogenic gases CH4, N2O, and CH3Cl have substantially longer lifetimes and higher mixing ratios than on Earth, making them potentially observable by space-based telescopes. On the active M-star planets, an ozone layer similar to Earth's was developed that resulted in a spectroscopic signature comparable to the terrestrial one. The simultaneous detection of O2 (or O3) and a reduced gas in a planet's atmosphere has been suggested as strong evidence for life. Planets circling M stars may be good locations to search for such evidence.

  17. The Occurrence of Earth-Like Planets Around Other Stars

    CERN Document Server

    Farr, Will M; Aldridge, Chris; Stroud, Kirsty

    2014-01-01

    The quantity $\\eta_\\oplus$, the number density of planets per star per logarithmic planetary radius per logarithmic orbital period at one Earth radius and one year period, describes the occurrence of Earth-like extrasolar planets. Here we present a measurement of $\\eta_\\oplus$ from a parameterised forward model of the (correlated) period-radius distribution and the observational selection function in the most recent (Q17) data release from the Kepler satellite. We find $\\eta_\\oplus = 3.9_{-1.6}^{+2.2}\\%$ (90% CL). We conclude that each star hosts $3.83_{-0.62}^{+0.76}$ planets with $P \\lesssim 3 \\mathrm{yr}$ and $R \\gtrsim 0.2 R_\\oplus$. Our empirical model for false-positive contamination is consistent with the dominant source being background eclipsing binary stars. The distribution of planets we infer is consistent with a highly-stochastic planet formation process producing many correlated, fractional changes in planet sizes and orbits.

  18. Is the Pale Blue Dot unique? Optimized photometric bands for identifying Earth-like exoplanets

    CERN Document Server

    Krissansen-Totton, Joshua; Charnay, Benjamin; Arney, Giada; Robinson, Tyler D; Meadows, Victoria; Catling, David C

    2015-01-01

    The next generation of ground and space-based telescopes will image habitable planets around nearby stars. A growing literature describes how to characterize such planets with spectroscopy, but less consideration has been given to the usefulness of planet colors. Here, we investigate whether potentially Earth-like exoplanets could be identified using UV-visible-to-NIR wavelength broadband photometry (350-1000 nm). Specifically, we calculate optimal photometric bins for identifying an exo-Earth and distinguishing it from uninhabitable planets including both Solar System objects and model exoplanets. The color of some hypothetical exoplanets - particularly icy terrestrial worlds with thick atmospheres - is similar to Earth's because of Rayleigh scattering in the blue region of the spectrum. Nevertheless, subtle features in Earth's reflectance spectrum appear to be unique. In particular, Earth's reflectance spectrum has a 'U-shape' unlike all our hypothetical, uninhabitable planets. This shape is partly biogenic...

  19. Atmospheric dynamics of Earth-like tidally locked aquaplanets

    Directory of Open Access Journals (Sweden)

    Tapio Schneider

    2010-12-01

    Full Text Available We present simulations of atmospheres of Earth-like aquaplanets that are tidally locked to their star, that is, planets whose orbital period is equal to the rotation period about their spin axis, so that one side always faces the star and the other side is always dark. Such simulations are of interest in the study of tidally locked terrestrial exoplanets and as illustrations of how planetary rotation and the insolation distribution shape climate. As extreme cases illustrating the effects of slow and rapid rotation, we consider planets with rotation periods equal to one current Earth year and one current Earth day. The dynamics responsible for the surface climate (e.g., winds, temperature, precipitation and the general circulation of the atmosphere are discussed in light of existing theories of atmospheric circulations. For example, as expected from the increasing importance of Coriolis accelerations relative to inertial accelerations as the rotation rate increases, the winds are approximately isotropic and divergent at leading order in the slowly rotating atmosphere but are predominantly zonal and rotational in the rapidly rotating atmosphere. Free-atmospheric horizontal temperature variations in the slowly rotating atmosphere are generally weaker than in the rapidly rotating atmosphere. Interestingly, the surface temperature on the night side of the planets does not fall below ~240 K in either the rapidly or slowly rotating atmosphere; that is, heat transport from the day side to the night side of the planets efficiently reduces temperature contrasts in either case. Rotational waves and eddies shape the distribution of winds, temperature, and precipitation in the rapidly rotating atmosphere; in the slowly rotating atmosphere, these distributions are controlled by simpler divergent circulations. Both the slowly and rapidly rotating atmospheres exhibit equatorial superrotation. Systematic variation of the planetary rotation rate shows that the

  20. Extraordinarily Warm Northeast Pacific Surface Waters: 2014 Observations

    Science.gov (United States)

    Mihaly, S. F.; Dewey, R. K.; Freeland, H.

    2015-12-01

    Analysis of sea surface temperatures (SST) from January 2014 revealed a massive region in the northeast Pacific with extraordinarily warm conditions, exceeding all anomalies over the last several decades. Profile data from both Argo and Line-P surveys supports the Reynolds SSTa analysis and further indicates that the anomaly was, and continues to be, confined to the upper ocean, above approximately 100 m depth. The anomaly has lasted for many months, exceeding 4 standard deviations above the multi-decadal mean, a feature that would not be expected more than once in several millennia. The "blob", as it is dubbed, drifted first off and then towards shore during the spring and fall of 2014 driven by, among other forces, the seasonal up and down-welling winds, respectively that occur along the west coast of North America. By November 2014, when winter down-welling winds became prevalent, the warm surface waters encroached all the way into Barkley Sound along western Vancouver Island, as measured by the continuous temperature measurements on the NEPTUNE ocean observatory of Ocean Networks Canada. The analysis includes some of the known dynamical variations which contributed to the formation of the blob, with an emphasis on mid to high latitude atmosphere-ocean conditions, avoiding the temptation to link the development processes occurring in the Gulf of Alaska in the winter of 2013 to equatorial phenomena.

  1. Iridate compound produces extraordinarily high coercive magnetic field

    Science.gov (United States)

    Zapf, Vivien; Topping, Craig; Kim, Jae-Wook; Mun, Eun-Deok; Goddard, Paul; Ghannadzadeh, Saman; Luo, Xuan; Cheong, Sang-Wook; Singleton, John

    2014-03-01

    We present a data on an iridate compound that shows an extraordinarily large magnetic hysteresis loop. The coercive magnetic field exceeds 40 Tesla in single-crystal samples. The hysteresis coexists with a linear background, and the total remanent magnetization is about half a Bohr magneton. We will discuss the emergence of these properties from the interplay of spin-orbit coupling, magnetic exchange and possible frustration. The single crystalline material exhibits a magnetic hysteresis loop for one orientation of the magnetic field and a smooth linear increase in the magnetization with field for the other. Measurements were conducted in 65 T short-pulse magnets and the 60 Tesla shaped-pulse magnet at the National High Magnetic Field Lab in Los Alamos. We do not observe any dependence of the magnetic hysteresis on magnetic field sweep rate. Compounds containing Ir4 + have attracted attention recently due to strong spin-orbit coupling that competes with crystal-electric field and exchange interactions. This competition can result in non-Hund's-rule ground states with unusual properties.

  2. 42 CFR 412.86 - Payment for extraordinarily high-cost day outliers.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Payment for extraordinarily high-cost day outliers... Outlier Cases, Special Treatment Payment for New Technology, and Payment Adjustment for Certain Replaced Devices Payment for Outlier Cases § 412.86 Payment for extraordinarily high-cost day outliers. For...

  3. Two extraordinarily severe cases of Treacher Collins syndrome.

    Science.gov (United States)

    Bauer, Mislen; Saldarriaga, Wilmar; Wolfe, S Anthony; Beckwith, J Bruce; Frias, Jaime L; Cohen, M Michael

    2013-03-01

    Here, we report two extraordinarily severe cases of Teacher Collins syndrome. Initially, amniotic bands and plical fold disruption were considered, but downslanting eyes made us consider severe Treacher Collins syndrome. A TCOF1 mutation in exon 24 was identified in Patient 1 (c.4355_4356ins14, resulting in p.1456Thrfs*18). Patient 2, who expired on day 4, is so similar to Patient 1 that severe Treacher Collins syndrome may be inferred in this instance. Neither the TCOF1 mutation nor the well-known variability in the expression in affected families with Treacher Collins syndrome (∼40% of reported cases) can explain the severity of these cases; otherwise, we would be aware of such cases within families from time to time. We are unaware of any recent sporadic cases (∼60% of reported cases) exactly like ours either with a single exception in the case reported by Writzl et al. [2008] with a TCOF1 mutation. The case described by Otto in 1841 is spectacular. We propose several hypotheses to be considered in explaining this developmental amplification, including some promoter effect on the gene, some position effect on the gene, a polymorphism elsewhere in the gene, a point mutation elsewhere in the gene, a polymorphism in another gene, or a point mutation in another gene, such as POLR1C (which maps to 6p21.1) or POLR1D (which maps to13q12.2). We also review the etiology and pathogenesis of Treacher Collins syndrome, and discuss several other severe cases from the past.

  4. A high-contrast coronagraph for earth-like exoplanet direct imaging: design and test

    CERN Document Server

    Liu, C C; Dou, J P; Zhu, Y T; Zhang, X; Zhao, G; Wu, Zh; Chen, R

    2014-01-01

    The high-contrast coronagraph for direct imaging earth-like exoplanet at the visible needs a contrast of 10^(-10) at a small angular separation of 4 lambda/D or less. Here we report our recent laboratory experiment that is close to the limits. The test of the high-contrast imaging coronagraph is based on our step-transmission apodized filter. To achieve the goal, we use a liquid crystal array (LCA) as a phase corrector to create a dark hole based on our dedicated focal dark algorithm. We have suppressed the diffracted and speckle noise near the star point image to a level of 1.68 x 10^(-9) at 4 lambda/D, which can be immediately used for the direct imaging of Jupiter like exoplanets. This demonstrates that high-contrast coronagraph telescope in space has the potentiality to detect and characterize earth-like planets.

  5. 3D climate modeling of Earth-like extrasolar planets orbiting different types of host stars

    CERN Document Server

    Godolt, M; Hamann-Reinus, A; Kitzmann, D; Kunze, M; Langematz, U; von Paris, P; Patzer, A B C; Rauer, H; Stracke, B

    2015-01-01

    The potential habitability of a terrestrial planet is usually defined by the possible existence of liquid water on its surface. The potential presence of liquid water depends on many factors such as, most importantly, surface temperatures. The properties of the planetary atmosphere and its interaction with the radiative energy provided by the planet's host star are thereby of decisive importance. In this study we investigate the influence of different main-sequence stars upon the climate of Earth-like extrasolar planets and their potential habitability by applying a 3D Earth climate model accounting for local and dynamical processes. The calculations have been performed for planets with Earth-like atmospheres at orbital distances where the total amount of energy received from the various host stars equals the solar constant. In contrast to previous 3D modeling studies, we include the effect of ozone radiative heating upon the vertical temperature structure of the atmospheres. The global orbital mean results o...

  6. On the equilibrium rotation of Earth-like extra-solar planets

    CERN Document Server

    Correia, Alexandre C M; Laskar, Jacques

    2008-01-01

    The equilibrium rotation of tidally evolved "Earth-like" extra-solar planets is often assumed to be synchronous with their orbital mean motion. The same assumption persisted for Mercury and Venus until radar observations revealed their true spin rates. As many of these planets follow eccentric orbits and are believed to host dense atmospheres, we expect the equilibrium rotation to differ from the synchronous motion. Here we provide a general description of the allowed final equilibrium rotation states of these planets, and apply this to already discovered cases in which the mass is lower than twelve Earth-masses. At low obliquity and moderate eccentricity, it is shown that there are at most four distinct equilibrium possibilities, one of which can be retrograde. Because most presently known "Earth-like" planets present eccentric orbits, their equilibrium rotation is unlikely to be synchronous.

  7. Habitable Zones for Earth-Like Planets in the 47UMa Planetary System

    Science.gov (United States)

    Ji, Jianghui; Liu, Lin

    The Habitable zones are usually believed to be appropriate environment for terrestrial planets that can provide the liquid-water, subtle temperature, atmosphere components of CO2, H2O, and N2 [Kasting et al., Icarus 101 (1993) 108], supporting the development and biological evolution of life on their surfaces. In this work [see an accompanied paper, Ji et al., Astrophysical Journal 631 (2005) 1191 for details], we investigated the dynamical architecture of 47 UMa with the planetary configuration of the best-fit orbital solutions by Fischer et al. [Astrophysical Journal 586 (2003) 1394], to study the existence of the Earth-like planets in the region for 0.05 AU ≤ a ≤ 2.0 AU for 47 UMa by numerical simulations. In the study, we found that the “hot Earths” at 0.05 AU ≤ a ≤ 0.4 AU can dynamically survive at least for 1 Myr. The Earth-like planets can eventually remain in the system for 10 Myr at the areas involved in mean motion resonance (MMR) (e.g., 3:2 MMR and 9:5 MMR) with the inner companion. Moreover, we showed that the 2:1 and 3:1 resonances could be marginally stable, but the 5:2 MMR is unstable. In a dynamical sense, we point out that the most possible candidate habitable environment is that the Earth-like planets may bear the orbits of 0.8 AU ≤ a ≤ 1.0 AU and 1.0 AU ≤ a ≤ 1.30 AU (except 5:2 MMR) for relatively lower eccentricities. We also conducted similar studies in other multi-planet systems and found the potential existence of the Earth-like planets in habitable zones.

  8. Dynamical Effects on the Habitable Zone for Earth-like Exomoons

    CERN Document Server

    Forgan, Duncan

    2013-01-01

    With the detection of extrasolar moons (exomoons) on the horizon, it is important to consider their potential for habitability. If we consider the circumstellar Habitable Zone (HZ, often described in terms of planet semi-major axis and orbital eccentricity), we can ask, "How does the HZ for an Earth-like exomoon differ from the HZ for an Earth-like exoplanet?" For the first time, we use 1D latitudinal energy balance modelling to address this question. The model places an Earth-like exomoon in orbit around a Jupiter mass planet, which in turn orbits a Sun-like star. The exomoon's surface temperature is evolved under the action of stellar insolation, atmospheric cooling, heat diffusion, eclipses and tidal heating. We use this model to carry out two separate investigations. In the first, four test cases are run to investigate in detail the dependence of the exomoon climate on orbital direction, orbital inclination, and on the frequency of stellar eclipse by the host planet. We find that lunar orbits which are re...

  9. Cosmic ray impact on extrasolar earth-like planets in close-in habitable zones.

    Science.gov (United States)

    Griessmeier, J-M; Stadelmann, A; Motschmann, U; Belisheva, N K; Lammer, H; Biernat, H K

    2005-10-01

    Because of their different origins, cosmic rays can be subdivided into galactic cosmic rays and solar/stellar cosmic rays. The flux of cosmic rays to planetary surfaces is mainly determined by two planetary parameters: the atmospheric density and the strength of the internal magnetic moment. If a planet exhibits an extended magnetosphere, its surface will be protected from high-energy cosmic ray particles. We show that close-in extrasolar planets in the habitable zone of M stars are synchronously rotating with their host star because of the tidal interaction. For gravitationally locked planets the rotation period is equal to the orbital period, which is much longer than the rotation period expected for planets not subject to tidal locking. This results in a relatively small magnetic moment. We found that an Earth-like extrasolar planet, tidally locked in an orbit of 0.2 AU around an M star of 0.5 solar masses, has a rotation rate of 2% of that of the Earth. This results in a magnetic moment of less than 15% of the Earth's current magnetic moment. Therefore, close-in extrasolar planets seem not to be protected by extended Earth-like magnetospheres, and cosmic rays can reach almost the whole surface area of the upper atmosphere. Primary cosmic ray particles that interact with the atmosphere generate secondary energetic particles, a so-called cosmic ray shower. Some of the secondary particles can reach the surface of terrestrial planets when the surface pressure of the atmosphere is on the order of 1 bar or less. We propose that, depending on atmospheric pressure, biological systems on the surface of Earth-like extrasolar planets at close-in orbital distances can be strongly influenced by secondary cosmic rays.

  10. 3D climate modeling of Earth-like extrasolar planets orbiting different types of host stars

    Science.gov (United States)

    Godolt, M.; Grenfell, J. L.; Hamann-Reinus, A.; Kitzmann, D.; Kunze, M.; Langematz, U.; von Paris, P.; Patzer, A. B. C.; Rauer, H.; Stracke, B.

    2015-06-01

    The potential habitability of a terrestrial planet is usually defined by the possible existence of liquid water on its surface, since life as we know it needs liquid water at least during a part of its life cycle. The potential presence of liquid water on a planetary surface depends on many factors such as, most importantly, surface temperatures. The properties of the planetary atmosphere and its interaction with the radiative energy provided by the planet's host star are thereby of decisive importance. In this study we investigate the influence of different main-sequence stars (F, G, and K-type stars) upon the climate of Earth-like extrasolar planets and their potential habitability by applying a state-of-the-art three-dimensional (3D) Earth climate model accounting for local and dynamical processes. The calculations have been performed for planets with Earth-like atmospheres at orbital distances (and corresponding orbital periods) where the total amount of energy received from the various host stars equals the solar constant. In contrast to previous 3D modeling studies, we include the effect of ozone radiative heating upon the vertical temperature structure of the atmospheres. The global orbital mean results obtained have been compared to those of a one-dimensional (1D) radiative convective climate model to investigate the approximation of global mean 3D results by those of 1D models. The different stellar spectral energy distributions lead to different surface temperatures and due to ozone heating to very different vertical temperature structures. As previous 1D studies we find higher surface temperatures for the Earth-like planet around the K-type star, and lower temperatures for the planet around the F-type star compared to an Earth-like planet around the Sun. However, this effect is more pronounced in the 3D model results than in the 1D model because the 3D model accounts for feedback processes such as the ice-albedo and the water vapor feedback. Whether the

  11. EPIC212521166 b: a Neptune-mass planet with Earth-like density

    CERN Document Server

    Osborn, H P; Barros, S C C; Armstrong, D J; Santos, N C; Hojjatpanah, S; Demangeon, O; Adibekyan, V; Almenara, J M; Barrado, D; Bayliss, D; Boisse, I; Bouchy, F; Brown, D J A; Deleuil, M; Mena, E Delgado; Hébrard, G; Kirk, J; King, G W; Lam, K W F; Lillo-Box, J; Louden, T M; Lovis, C; Marmier, M; McCormac, J; Pollacco, D; Sousa, S G; Udry, S; Walker, S R

    2016-01-01

    We report the discovery of the exoplanet EPIC212521166 b from K2 photometry orbiting on a 13.8637d period around an old, metal-poor K3 dwarf star. A joint analysis of K2 photometry and high-precision RVs from HARPS reveals it to have a radius of 2.6$\\pm 0.1 R_{\\oplus}$ and a mass of 18.3$\\pm 2.8 M_{\\oplus}$, making it the most massive planet with a sub-Neptune radius (i.e. mini-Neptune) yet found. When accounting for compression, the resulting Earth-like density is best fit by a $0.2M_{\\oplus}$ hydrogen atmosphere over an $18M_{\\oplus}$ Earth-like core, although the planet could also have significant water content. At 0.1AU, even taking into account the old stellar age of $8 \\pm 3$ Gyr, the planet is unlikely to have been significantly affected by EUV evaporation or tides. However the planet likely disc-migrated to its current position making the lack of a thick H$_2$ atmosphere puzzling. With a V-band magnitude of 11.9 it is particularly amenable to follow-up observations, making EPIC-1166 b a rare and extre...

  12. 3D climate simulations of an Earth-like circumbinary planet

    Science.gov (United States)

    Popp, Max; Eggl, Siegfried

    2017-04-01

    Planets orbiting close binary-star systems experience strong variations in insolation that are due to the non-trivial evolution of the distance between the planet and the two stars. Previous studies have suggested that these variations in insolation could influence the habitability of Earth-like circumbinary planets. In contrast to previous work using one-dimensional models that lack important climate dynamics, we performed for the first time simulations of a hypothetical Earth-like circumbinary planet with a three-dimensional atmospheric general circulation model coupled to an analytical orbital propagator. We choose a Kepler-35-like setup without the gas-giant that is present in the actual system in order to investigate the effects of the variable total solar irradiance (TSI) originating from the double star on the planet's climate. For fixed CO2 concentrations we find that an aqua-planet (a fully water-covered planet) can maintain a habitable climate at TSI values similar to those an identical planet receives orbiting our sun. The variations in TSI have, however, various effects on the climate of the planet. Signatures of these periodic variations are clearly visible in important climate indicators such as surface temperature and precipitation. Moreover, the periodic forcing leads to a cooling of the mean climate, especially in cold climate regimes.

  13. Effect of UV Radiation on the Spectral Fingerprints of Earth-like Planets Orbiting M dwarfs

    CERN Document Server

    Rugheimer, S; Segura, A; Linsky, J; Mohanty, S

    2015-01-01

    We model the atmospheres and spectra of Earth-like planets orbiting the entire grid of M dwarfs for active and inactive stellar models with $T_{eff}$ = 2300K to $T_{eff}$ = 3800K and for six observed MUSCLES M dwarfs with UV radiation data. We set the Earth-like planets at the 1AU equivalent distance and show spectra from the VIS to IR (0.4$\\mu$m - 20$\\mu$m) to compare detectability of features in different wavelength ranges with JWST and other future ground- and spaced-based missions to characterize exo-Earths. We focus on the effect of UV activity levels on detectable atmospheric features that indicate habitability on Earth, namely: H$_2$O, O$_3$, CH$_4$, N$_2$O and CH$_3$Cl. To observe signatures of life - O$_2$/O$_3$ in combination with reducing species like CH$_4$, we find that early and active M dwarfs are the best targets of the M star grid for future telescopes. The O$_2$ spectral feature at 0.76$\\mu$m is increasingly difficult to detect in reflected light of later M dwarfs due to low stellar flux in ...

  14. Dynamical Stability of Earth-Like Planetary Orbits in Binary Systems

    CERN Document Server

    David, E M; Fatuzzo, M; Adams, F C; David, Eva-Marie; Quintana, Elisa V.; Fatuzzo, Marco; Adams, Fred C.

    2003-01-01

    This paper explores the stability of an Earth-like planet orbiting a solar mass star in the presence of an outer-lying intermediate mass companion. The overall goal is to estimate the fraction of binary systems that allow Earth-like planets to remain stable over long time scales. We numerically determine the planet's ejection time $\\tauej$ over a range of companion masses ($M_C$ = 0.001 -- 0.5 $M_\\odot$), orbital eccentricities $\\epsilon$, and semi-major axes $a$. This suite of $\\sim40,000$ numerical experiments suggests that the most important variables are the companion's mass $M_C$ and periastron distance $\\rmin$ = $a(1-\\epsilon)$ to the primary star. At fixed $M_C$, the ejection time is a steeply increasing function of $\\rmin$ over the range of parameter space considered here (although the ejection time has a distribution of values for a given $\\rmin$). Most of the integration times are limited to 10 Myr, but a small set of integrations extend to 500 Myr. For each companion mass, we find fitting formulae ...

  15. CO2 condensation is a serious limit to the deglaciation of Earth-like planets

    Science.gov (United States)

    Turbet, Martin; Forget, Francois; Leconte, Jeremy; Charnay, Benjamin; Tobie, Gabriel

    2017-10-01

    It is widely believed that the carbonate-silicate cycle is the main agent, through volcanism, to trigger deglaciations by CO2 greenhouse warming on Earth and on Earth-like planets when they get in a frozen state. Here we use a 3D Global Climate Model to simulate the ability of planets initially completely frozen to escape from glaciation episodes by accumulating enough gaseous CO2. The model includes CO2 condensation and sublimation processes and the water cycle. We find that planets with Earth-like characteristics (size, mass, obliquity, rotation rate, etc.) orbiting a Sun-like star may never be able to escape from a glaciation era, if their orbital distance is greater than ∼1.27 Astronomical Units (Flux pressures ( 0.6), this critical limit could occur at a significantly lower equivalent distance (or higher insolation). For each possible configuration, we show that the amount of CO2 that can be trapped in the polar caps depends on the efficiency of CO2 ice to flow laterally as well as its gravitational stability relative to subsurface water ice. We find that a frozen Earth-like planet located at 1.30 AU of a Sun-like star could store as much as 1.5, 4.5 and 15 bars of dry ice at the poles, for internal heat fluxes of 100, 30 and 10 mW m-2, respectively. But these amounts are in fact lower limits. For planets with a significant water ice cover, we show that CO2 ice deposits should be gravitationally unstable. They get buried beneath the water ice cover in geologically short timescales of ∼104 yrs, mainly controlled by the viscosity of water ice. CO2 would be permanently sequestered underneath the water ice cover, in the form of CO2 liquids, CO2 clathrate hydrates and/or dissolved in subglacial water reservoirs (if any). This would considerably increase the amount of CO2 trapped and further reduce the probability of deglaciation.

  16. 42 CFR 412.84 - Payment for extraordinarily high-cost cases (cost outliers).

    Science.gov (United States)

    2010-10-01

    ... outliers). 412.84 Section 412.84 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF... Payments for Outlier Cases, Special Treatment Payment for New Technology, and Payment Adjustment for Certain Replaced Devices Payment for Outlier Cases § 412.84 Payment for extraordinarily high-cost cases...

  17. Evolution of Earth-like Extrasolar Planetary Atmospheres: Assessing the Atmospheres and Biospheres of Early Earth Analog Planets with a Coupled Atmosphere Biogeochemical Model

    Science.gov (United States)

    Gebauer, S.; Grenfell, J. L.; Stock, J. W.; Lehmann, R.; Godolt, M.; von Paris, P.; Rauer, H.

    2017-01-01

    Understanding the evolution of Earth and potentially habitable Earth-like worlds is essential to fathom our origin in the Universe. The search for Earth-like planets in the habitable zone and investigation of their atmospheres with climate and photochemical models is a central focus in exoplanetary science. Taking the evolution of Earth as a reference for Earth-like planets, a central scientific goal is to understand what the interactions were between atmosphere, geology, and biology on early Earth. The Great Oxidation Event in Earth's history was certainly caused by their interplay, but the origin and controlling processes of this occurrence are not well understood, the study of which will require interdisciplinary, coupled models. In this work, we present results from our newly developed Coupled Atmosphere Biogeochemistry model in which atmospheric O2 concentrations are fixed to values inferred by geological evidence. Applying a unique tool (Pathway Analysis Program), ours is the first quantitative analysis of catalytic cycles that governed O2 in early Earth's atmosphere near the Great Oxidation Event. Complicated oxidation pathways play a key role in destroying O2, whereas in the upper atmosphere, most O2 is formed abiotically via CO2 photolysis. The O2 bistability found by Goldblatt et al. (2006) is not observed in our calculations likely due to our detailed CH4 oxidation scheme. We calculate increased CH4 with increasing O2 during the Great Oxidation Event. For a given atmospheric surface flux, different atmospheric states are possible; however, the net primary productivity of the biosphere that produces O2 is unique. Mixing, CH4 fluxes, ocean solubility, and mantle/crust properties strongly affect net primary productivity and surface O2 fluxes. Regarding exoplanets, different "states" of O2 could exist for similar biomass output. Strong geological activity could lead to false negatives for life (since our analysis suggests that reducing gases remove O2 that

  18. Galactic cosmic rays on extrasolar Earth-like planets: II. Atmospheric implications

    CERN Document Server

    Grießmeier, J --M; Stadelmann, A; Grenfell, J L; Atri, D

    2016-01-01

    (abridged abstract) Theoretical arguments indicate that close-in terrestial exoplanets may have weak magnetic fields. As described in the companion article (Paper I), a weak magnetic field results in a high flux of galactic cosmic rays to the top of the planetary atmosphere. We investigate effects that may result from a high flux of galactic cosmic rays both throughout the atmosphere and at the planetary surface. Using an air shower approach, we calculate how the atmospheric chemistry and temperature change under the influence of galactic cosmic rays for Earth-like (N_2-O_2 dominated) atmospheres. We evaluate the production and destruction rate of atmospheric biosignature molecules. We derive planetary emission and transmission spectra to study the influence of galactic cosmic rays on biosignature detectability. We then calculate the resulting surface UV flux, the surface particle flux, and the associated equivalent biological dose rates. We find that up to 20% of stratospheric ozone is destroyed by cosmic-ra...

  19. Wavefront error correction and Earth-like planet detection by Self-Coherent Camera in space

    CERN Document Server

    Galicher, R; Rousset, G

    2008-01-01

    In the context of exoplanet detection, the performance of coronagraphs is limited by wavefront errors. To efficiently correct for these aberrations with a deformable mirror, it is mandatory to measure them using the science detector with a very high accuracy. The Self-Coherent Camera which is based on light incoherence between star and its environment enables an estimation of these wavefront errors. That estimation is directly derived from the encoded speckles in the science image. This avoids differential errors due to beam separation and non common optics. Earth-like planet detection is demonstrated by numerical simulations under realistic assumptions for a space telescope. The Self-Coherent Camera is an attractive technique for future space telescopes. It is also one of the techniques under investigation for the E-ELT planet finder so-called EPICS.

  20. Increased insolation threshold for runaway greenhouse processes on Earth like planets

    CERN Document Server

    Leconte, Jérémy; Charnay, Benjamin; Wordsworth, Robin; Pottier, Alizée

    2013-01-01

    Because the solar luminosity increases over geological timescales, Earth climate is expected to warm, increasing water evaporation which, in turn, enhances the atmospheric greenhouse effect. Above a certain critical insolation, this destabilizing greenhouse feedback can "runaway" until all the oceans are evaporated. Through increases in stratospheric humidity, warming may also cause oceans to escape to space before the runaway greenhouse occurs. The critical insolation thresholds for these processes, however, remain uncertain because they have so far been evaluated with unidimensional models that cannot account for the dynamical and cloud feedback effects that are key stabilizing features of Earth's climate. Here we use a 3D global climate model to show that the threshold for the runaway greenhouse is about 375 W/m$^2$, significantly higher than previously thought. Our model is specifically developed to quantify the climate response of Earth-like planets to increased insolation in hot and extremely moist atmo...

  1. Quantum degenerate mixtures of alkali and alkaline-earth-like atoms.

    Science.gov (United States)

    Hara, Hideaki; Takasu, Yosuke; Yamaoka, Yoshifumi; Doyle, John M; Takahashi, Yoshiro

    2011-05-20

    We realize simultaneous quantum degeneracy in mixtures consisting of the alkali and alkaline-earth-like atoms Li and Yb. This is accomplished within an optical trap by sympathetic cooling of the fermionic isotope ⁶Li with evaporatively cooled bosonic ¹⁷⁴Yb and, separately, fermionic ¹⁷³Yb. Using cross-thermalization studies, we also measure the elastic s-wave scattering lengths of both Li-Yb combinations, |a(⁶Li-¹⁷⁴Yb)| = 1.0 ± 0.2 nm and |a(⁶Li-¹⁷³Yb)| = 0.9 ± 0.2 nm. The equality of these lengths is found to be consistent with mass-scaling analysis. The quantum degenerate mixtures of Li and Yb, as realized here, can be the basis for creation of ultracold molecules with electron spin degrees of freedom, studies of novel Efimov trimers, and impurity probes of superfluid systems.

  2. Free oscillations of the earth-like planets in the presence of magnetic field

    Directory of Open Access Journals (Sweden)

    Y. Abedini

    2005-12-01

    Full Text Available   we study the free oscillations of a non-rotating earth-like planet in the presence of a force free magnetic field. The model consists of a solid inner core, a liquid outer core and a solid mantle which is spherically symmetric. The lagrangian displacements are decomposed into scaloidal, poloidal and toroidal components using a gauged version of Helmholtz theorem. These components are identified, with P- , g and t- modes, respectively. The normal modes of the model are determined using a Rayleigh-Ritz variational technique. The consequence of the presence of the solid parts and the magnetic field is the emergence of pure t- oscillations. The magnetic field, in addition to exciting t- modes, couples the everpresent p- and g -modes together. As an application of the model, the real seismic data of the earth is used to calculate eigenvalues and eigenvectors for different modes.

  3. Photon Hall Scattering from Alkaline-earth-like atoms and Alkali-like ions

    CERN Document Server

    van Tiggelen, B A

    2016-01-01

    We investigate the possibility of observing a magneto-transverse scattering of photons from alkaline-earth-like atoms as well as alkali-like ions and provide orders of magnitude. The transverse magneto-scattering is physically induced by the interference between two possible quantum transitions of an outer electron in a S-state, one dispersive electric-dipole transition to a P-orbital state and a second resonant electric-quadrupole transition to a P-orbital state. In contrast with previous mechanisms proposed for such an atomic photonic Hall effect, no real photons are scattered by the electric-dipole allowed transition, which increases the ratio of Hall current to background photons significantly. The main experimental challenge is to overcome the small detection threshold, with only 10^{-5} photons scattered per atom per second.

  4. Evolution of Earth-like Extrasolar Planetary Atmospheres: Assessing the Atmospheres and Biospheres of Early Earth Analog Planets with a Coupled Atmosphere Biogeochemical Model.

    Science.gov (United States)

    Gebauer, S; Grenfell, J L; Stock, J W; Lehmann, R; Godolt, M; von Paris, P; Rauer, H

    2017-01-01

    Understanding the evolution of Earth and potentially habitable Earth-like worlds is essential to fathom our origin in the Universe. The search for Earth-like planets in the habitable zone and investigation of their atmospheres with climate and photochemical models is a central focus in exoplanetary science. Taking the evolution of Earth as a reference for Earth-like planets, a central scientific goal is to understand what the interactions were between atmosphere, geology, and biology on early Earth. The Great Oxidation Event in Earth's history was certainly caused by their interplay, but the origin and controlling processes of this occurrence are not well understood, the study of which will require interdisciplinary, coupled models. In this work, we present results from our newly developed Coupled Atmosphere Biogeochemistry model in which atmospheric O2 concentrations are fixed to values inferred by geological evidence. Applying a unique tool (Pathway Analysis Program), ours is the first quantitative analysis of catalytic cycles that governed O2 in early Earth's atmosphere near the Great Oxidation Event. Complicated oxidation pathways play a key role in destroying O2, whereas in the upper atmosphere, most O2 is formed abiotically via CO2 photolysis. The O2 bistability found by Goldblatt et al. ( 2006 ) is not observed in our calculations likely due to our detailed CH4 oxidation scheme. We calculate increased CH4 with increasing O2 during the Great Oxidation Event. For a given atmospheric surface flux, different atmospheric states are possible; however, the net primary productivity of the biosphere that produces O2 is unique. Mixing, CH4 fluxes, ocean solubility, and mantle/crust properties strongly affect net primary productivity and surface O2 fluxes. Regarding exoplanets, different "states" of O2 could exist for similar biomass output. Strong geological activity could lead to false negatives for life (since our analysis suggests that reducing gases remove O2 that

  5. Geodynamics and Rate of Volcanism on Massive Earth-like Planets

    CERN Document Server

    Kite, Edwin S; Gaidos, Eric

    2008-01-01

    We provide estimates of volcanism versus time for planets with Earth-like composition and masses from 0.25 to 25 times Earth, as a step toward predicting atmospheric mass on extrasolar rocky planets. Volcanism requires melting of the silicate mantle. We use a thermal evolution model, calibrated against Earth, in combination with standard melting models, to explore the dependence of convection-driven decompression mantle melting on planet mass. Here we show that (1) volcanism is likely to proceed on massive planets with plate tectonics over the main-sequence lifetime of the parent star; (2) crustal thickness (and melting rate normalized to planet mass) is weakly dependent on planet mass; (3) stagnant lid planets can have higher rates of melting than their plate tectonic counterparts early in their thermal evolution, but melting shuts down after a few Gyr; (4) plate tectonics may not operate on high mass planets because of the production of buoyant crust which is difficult to subduct; and (5) melting is necessa...

  6. Control of Earth-like magnetic fields on the transformation of ferrihydrite to hematite and goethite.

    Science.gov (United States)

    Jiang, Zhaoxia; Liu, Qingsong; Dekkers, Mark J; Barrón, Vidal; Torrent, José; Roberts, Andrew P

    2016-07-26

    Hematite and goethite are the two most abundant iron oxides in natural environments. Their formation is controlled by multiple environmental factors; therefore, their relative concentration has been used widely to indicate climatic variations. In this study, we aimed to test whether hematite and goethite growth is influenced by ambient magnetic fields of Earth-like values. Ferrihydrite was aged at 95 °C in magnetic fields ranging from ~0 to ~100 μT. Our results indicate a large influence of the applied magnetic field on hematite and goethite growth from ferrihydrite. The synthesized products are a mixture of hematite and goethite for field intensities fields favour hematite formation by accelerating ferrimagnetic ferrihydrite aggregation. Additionally, hematite particles growing in a controlled magnetic field of ~100 μT appear to be arranged in chains, which may be reduced to magnetite keeping its original configuration, therefore, the presence of magnetic particles in chains in natural sediments cannot be used as an exclusive indicator of biogenic magnetite. Hematite vs. goethite formation in our experiments is influenced by field intensity values within the range of geomagnetic field variability. Thus, geomagnetic field intensity could be a source of variation when using iron (oxyhydr-)oxide concentrations in environmental magnetism.

  7. Atmospheric effects of stellar cosmic rays on Earth-like exoplanets orbiting M-dwarfs

    CERN Document Server

    Tabataba-Vakili, F; Grießmeier, J -M; Rauer, H

    2016-01-01

    M-dwarf stars are generally considered favourable for rocky planet detection. However, such planets may be subject to extreme conditions due to possible high stellar activity. The goal of this work is to determine the potential effect of stellar cosmic rays on key atmospheric species of Earth-like planets orbiting in the habitable zone of M-dwarf stars and show corresponding changes in the planetary spectra. We build upon the cosmic rays model scheme of Grenfell et al. (2012), who considered cosmic ray induced NOx production, by adding further cosmic ray induced production mechanisms (e.g. for HOx) and introducing primary protons of a wider energy range (16 MeV - 0.5 TeV). Previous studies suggested that planets in the habitable zone that are subject to strong flaring conditions have high atmospheric methane concentrations, while their ozone biosignature is completely destroyed. Our current study shows, however, that adding cosmic ray induced HOx production can cause a decrease in atmospheric methane abundanc...

  8. VizieR Online Data Catalog: Catalog of Earth-Like Exoplanet Survey Targets (Chandler+, 2016)

    Science.gov (United States)

    Chandler, C. O.; McDonald, I.; Kane, S. R.

    2016-07-01

    We present the Catalog of Earth-Like Exoplanet Survey Targets (CELESTA), a database of habitable zones around 37000 nearby stars. The first step in creating CELESTA was assembling the input data. The Revised Hipparcos Catalog (van Leeuwen 2007, Cat. I/311) is a stellar catalog based on the original Hipparcos mission (Perryman et al. 1997, Cat. I/239) data set. Hipparcos, launched in 1989, recorded with great precision the parallax of nearby stars, ultimately leading to a database of 118218 stars. McDonald et al. 2012 (cat. J/MNRAS/427/343) calculated effective temperatures and luminosities for the Hipparcos stars. The next step was selecting appropriate stars for the construction of CELESTA. The Stellar Parameter Catalog of 103663 stars included many stars that were not suitable for our purposes, especially stars off the Main-Sequence (MS) branch, e.g., giants. Please refer to Section 3.2 in the paper for additional details about the star selection. The final CELESTA catalog contains 37354 stars (see Table2), each with a set of associated attributes, e.g., estimated mass, measured distance. The complete database can also be found online at a dedicated host (http://www.celesta.info/). (2 data files).

  9. Science cases for the OWL Earth-like planet imager and spectrograph (EPICS)

    Science.gov (United States)

    Beuzit, J.-L.; Gratton, R.; Kasper, M.; Desidera, S.; Kerber, F.; Rahoui, F.; Mouillet, D.; Rouan, D.; Turatto, M.; Feldt, M.; Schmid, H.-M.; Stam, D.; Selsis, F.; Hubin, N.; Vérinaud, C.

    The extreme contrast in mass and luminosity between the extra-solar planets and their host stars make detailed studies of these planets very challenging. In particular, direct observations of extra-solar planets is still beyond the capabilities of the currently available instrumentation, save for perhaps a few extreme cases of very young and massive planets at large distances from the central star. While progress in instrumentation might allow significant progress in detection capabilities either with the 8 and 10-m ground-based telescopes (Planet Finder instruments on the VLT and Gemini) or with the next generation space telescope (JWST), imaging of extra-solar planets over a wide range of parameters, and possibly down to terrestrial planets, will require extremely large ground-based telescopes like OWL or dedicated space instrumentation (TPF or Darwin for instance). We outline here the scientific objectives of EPICS, the OWL Earth-like Planet Imager and Spectrograph, summarize the corresponding high level requirements, present the foreseen observing modes and give a first estimate of its performance.

  10. UV SURFACE ENVIRONMENT OF EARTH-LIKE PLANETS ORBITING FGKM STARS THROUGH GEOLOGICAL EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Rugheimer, S.; Sasselov, D. [Harvard Smithsonian Center for Astrophysics, 60 Garden st., 02138 MA Cambridge (United States); Segura, A. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, México (Mexico); Kaltenegger, L., E-mail: srugheimer@cfa.harvard.edu [Carl Sagan Institute, Cornell University, Ithaca, NY 14853 (United States)

    2015-06-10

    The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars in the circumstellar Habitable Zone for Earth through its geological evolution. We explore four different types of atmospheres corresponding to an early-Earth atmosphere at 3.9 Gyr ago and three atmospheres covering the rise of oxygen to present-day levels at 2.0 Gyr ago, 0.8 Gyr ago, and modern Earth. In addition to calculating the UV flux on the surface of the planet, we model the biologically effective irradiance, using DNA damage as a proxy for biological damage. We find that a pre-biotic Earth (3.9 Gyr ago) orbiting an F0V star receives 6 times the biologically effective radiation as around the early Sun and 3520 times the modern Earth–Sun levels. A pre-biotic Earth orbiting GJ 581 (M3.5 V) receives 300 times less biologically effective radiation, about 2 times modern Earth–Sun levels. The UV fluxes calculated here provide a grid of model UV environments during the evolution of an Earth-like planet orbiting a range of stars. These models can be used as inputs into photo-biological experiments and for pre-biotic chemistry and early life evolution experiments.

  11. The habitable zone of Earth-like planets with different levels of atmospheric pressure

    CERN Document Server

    Vladilo, Giovanni; Silva, Laura; Provenzale, Antonello; Ferri, Gaia; Ragazzini, Gregorio

    2013-01-01

    As a contribution to the study of the habitability of extrasolar planets, we implemented a 1-D Energy Balance Model (EBM), the simplest seasonal model of planetary climate, with new prescriptions for most physical quantities. Here we apply our EBM to investigate the surface habitability of planets with an Earth-like atmospheric composition but different levels of surface pressure. The habitability, defined as the mean fraction of the planet's surface on which liquid water could exist, is estimated from the pressure-dependent liquid water temperature range, taking into account seasonal and latitudinal variations of surface temperature. By running several thousands of EBM simulations we generated a map of the habitable zone (HZ) in the plane of the orbital semi-major axis, a, and surface pressure, p, for planets in circular orbits around a Sun-like star. As pressure increases, the HZ becomes broader, with an increase of 0.25 AU in its radial extent from p=1/3 bar to p=3 bar. At low pressure, the habitability is...

  12. THE HABITABILITY AND DETECTION OF EARTH-LIKE PLANETS ORBITING COOL WHITE DWARFS

    Energy Technology Data Exchange (ETDEWEB)

    Fossati, L.; Haswell, C. A.; Patel, M. R.; Busuttil, R. [Department of Physical Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom); Bagnulo, S. [Armagh Observatory, College Hill, Armagh BT61 9DG (United Kingdom); Kowalski, P. M. [GFZ German Research Centre for Geosciences, Telegrafenberg, D-14473 Potsdam (Germany); Shulyak, D. V. [Institute of Astrophysics, Georg-August-University, Friedrich-Hund-Platz 1, D-37077 Goettingen (Germany); Sterzik, M. F., E-mail: l.fossati@open.ac.uk, E-mail: C.A.Haswell@open.ac.uk, E-mail: M.R.Patel@open.ac.uk, E-mail: r.busuttil@open.ac.uk, E-mail: sba@arm.ac.uk, E-mail: kowalski@gfz-potsdam.de, E-mail: denis.shulyak@gmail.com, E-mail: msterzik@eso.org [European Southern Observatory, Casilla 19001, Santiago 19 (Chile)

    2012-09-20

    Since there are several ways planets can survive the giant phase of the host star, we examine the habitability and detection of planets orbiting white dwarfs. As a white dwarf cools from 6000 K to 4000 K, a planet orbiting at 0.01 AU would remain in the continuous habitable zone (CHZ) for {approx}8 Gyr. We show that photosynthetic processes can be sustained on such planets. The DNA-weighted UV radiation dose for an Earth-like planet in the CHZ is less than the maxima encountered on Earth, and hence non-magnetic white dwarfs are compatible with the persistence of complex life. Polarization due to a terrestrial planet in the CHZ of a cool white dwarf (CWD) is 10{sup 2} (10{sup 4}) times larger than it would be in the habitable zone of a typical M-dwarf (Sun-like star). Polarimetry is thus a viable way to detect close-in rocky planets around white dwarfs. Multi-band polarimetry would also allow us to reveal the presence of a planet atmosphere, providing a first characterization. Planets in the CHZ of a 0.6 M{sub Sun} white dwarf will be distorted by Roche geometry, and a Kepler-11d analog would overfill its Roche lobe. With current facilities a super-Earth-sized atmosphereless planet is detectable with polarimetry around the brightest known CWD. Planned future facilities render smaller planets detectable, in particular by increasing the instrumental sensitivity in the blue.

  13. Detecting industrial pollution in the atmospheres of earth-like exoplanets

    CERN Document Server

    Lin, Henry W; Loeb, Abraham

    2014-01-01

    Detecting biomarkers, such as molecular oxygen, in the atmospheres of transiting exoplanets has been a major focus in the search for alien life. We point out that in addition to these generic indicators, anthropogenic pollution could be used as a novel biomarker for intelligent life. To this end, we identify pollutants in the Earth's atmosphere that have significant absorption features in the spectral range covered by the James Webb Space Telescope (JWST). We estimate that for an Earth-mass planet in the habitable zone of a white dwarf, methane (CH4) and nitrous oxide (N2O) can be detected at earth-like concentrations with an integration time of ~1.5 hrs and 12 hrs respectively. Detecting pollutants that are produced nearly exclusively by anthropogenic activities will be significantly more challenging. Of these pollutants, we focus on tetrafluoromethane (CF4) and trichlorofluoromethane (CCl3F), which will be the easiest to detect. We estimate that ~1.5 days (~3 days) of total integration time will be sufficie...

  14. Control of Earth-like magnetic fields on the transformation of ferrihydrite to hematite and goethite

    Science.gov (United States)

    Jiang, Zhaoxia; Liu, Qingsong; Dekkers, Mark J.; Barrón, Vidal; Torrent, José; Roberts, Andrew P.

    2016-07-01

    Hematite and goethite are the two most abundant iron oxides in natural environments. Their formation is controlled by multiple environmental factors; therefore, their relative concentration has been used widely to indicate climatic variations. In this study, we aimed to test whether hematite and goethite growth is influenced by ambient magnetic fields of Earth-like values. Ferrihydrite was aged at 95 °C in magnetic fields ranging from ~0 to ~100 μT. Our results indicate a large influence of the applied magnetic field on hematite and goethite growth from ferrihydrite. The synthesized products are a mixture of hematite and goethite for field intensities <~60 μT. Higher fields favour hematite formation by accelerating ferrimagnetic ferrihydrite aggregation. Additionally, hematite particles growing in a controlled magnetic field of ~100 μT appear to be arranged in chains, which may be reduced to magnetite keeping its original configuration, therefore, the presence of magnetic particles in chains in natural sediments cannot be used as an exclusive indicator of biogenic magnetite. Hematite vs. goethite formation in our experiments is influenced by field intensity values within the range of geomagnetic field variability. Thus, geomagnetic field intensity could be a source of variation when using iron (oxyhydr-)oxide concentrations in environmental magnetism.

  15. Modeling the Entry of Micrometeoroids into the Atmospheres of Earth-like Planets

    Science.gov (United States)

    Pevyhouse, A. R.; Kress, M. E.

    2011-01-01

    The temperature profiles of micrometeors entering the atmospheres of Earth-like planets are calculated to determine the altitude at which exogenous organic compounds may be released. Previous experiments have shown that flash-heated micrometeorite analogs release organic compounds at temperatures from roughly 500 to 1000 K [1]. The altitude of release is of great importance because it determines the fate of the compound. Organic compounds that are released deeper in the atmosphere are more likely to rapidly mix to lower altitudes where they can accumulate to higher abundances or form more complex molecules and/or aerosols. Variables that are explored here are particle size, entry angle, atmospheric density profiles, spectral type of the parent star, and planet mass. The problem reduces to these questions: (1) How much atmosphere does the particle pass through by the time it is heated to 500 K? (2) Is the atmosphere above sufficient to attenuate stellar UV such that the mixing timescale is shorter than the photochemical timescale for a particular compound? We present preliminary results that the effect of the planetary and particle parameters have on the altitude of organic release.

  16. The Earth as a Distant Planet A Rosetta Stone for the Search of Earth-Like Worlds

    CERN Document Server

    Vázquez, M; Montañés Rodríguez, P

    2010-01-01

    Is the Earth, in some way, special? Or is our planet but one of the millions of other inhabited planets within our galaxy? This is an exciting time to be asking this old question, because for the first time in history, the answer is within reach. In The Earth as a Distant Planet, the authors set themselves as external observers of our Solar System from an astronomical distance. From that perspective, the authors describe how the Earth, the third planet in distance to the central star, can be catalogued as having its own unique features and as capable of sustaining life. The knowledge gained from this original perspective is then applied to the ongoing search for planets outside the solar system, or exoplanets. Since the discovery in 1992 of the first exoplanet, the number of known planets has increased exponentially. Ambitious space missions are already being designed for the characterization of their atmospheres and to explore the possibility that they host life. The exploration of Earth and the rest of the ...

  17. Influence of Sudden Change of Solar Mass in the PN Stage on the Orbit of Earth-Like Planet

    Indian Academy of Sciences (India)

    Yunfeng Zhu; Caijuan Pan; Dasheng Pan; Hongqiang Huang; Zhi-Fu Chen

    2014-09-01

    Assuming that the terminated mass is confined within the range 0.4551-0.5813⊙ when the sun is going to evolve into a white dwarf, the velocity of the sun projecting the shell in the PN stage is much greater than the revolving velocity of the earth-like planet, therefore, we think that the solar mass change is instantaneous.

  18. Increased insolation threshold for runaway greenhouse processes on Earth-like planets.

    Science.gov (United States)

    Leconte, Jérémy; Forget, Francois; Charnay, Benjamin; Wordsworth, Robin; Pottier, Alizée

    2013-12-12

    The increase in solar luminosity over geological timescales should warm the Earth's climate, increasing water evaporation, which will in turn enhance the atmospheric greenhouse effect. Above a certain critical insolation, this destabilizing greenhouse feedback can 'run away' until the oceans have completely evaporated. Through increases in stratospheric humidity, warming may also cause evaporative loss of the oceans to space before the runaway greenhouse state occurs. The critical insolation thresholds for these processes, however, remain uncertain because they have so far been evaluated using one-dimensional models that cannot account for the dynamical and cloud feedback effects that are key stabilizing features of the Earth's climate. Here we use a three-dimensional global climate model to show that the insolation threshold for the runaway greenhouse state to occur is about 375 W m(-2), which is significantly higher than previously thought. Our model is specifically developed to quantify the climate response of Earth-like planets to increased insolation in hot and extremely moist atmospheres. In contrast with previous studies, we find that clouds have a destabilizing feedback effect on the long-term warming. However, subsident, unsaturated regions created by the Hadley circulation have a stabilizing effect that is strong enough to shift the runaway greenhouse limit to higher values of insolation than are inferred from one-dimensional models. Furthermore, because of wavelength-dependent radiative effects, the stratosphere remains sufficiently cold and dry to hamper the escape of atmospheric water, even at large fluxes. This has strong implications for the possibility of liquid water existing on Venus early in its history, and extends the size of the habitable zone around other stars.

  19. Atmospheric effects of stellar cosmic rays on Earth-like exoplanets orbiting M-dwarfs

    Science.gov (United States)

    Tabataba-Vakili, F.; Grenfell, J. L.; Grießmeier, J.-M.; Rauer, H.

    2016-01-01

    M-dwarf stars are generally considered favourable for rocky planet detection. However, such planets may be subject to extreme conditions due to possible high stellar activity. The goal of this work is to determine the potential effect of stellar cosmic rays on key atmospheric species of Earth-like planets orbiting in the habitable zone of M-dwarf stars and show corresponding changes in the planetary spectra. We build upon the cosmic rays model scheme of previous works, who considered cosmic ray induced NOx production, by adding further cosmic ray induced production mechanisms (e.g. for HOx) and introducing primary protons of a wider energy range (16 MeV-0.5 TeV). Previous studies suggested that planets in the habitable zone that are subject to strong flaring conditions have high atmospheric methane concentrations, while their ozone biosignature is completely destroyed. Our current study shows, however, that adding cosmic ray induced HOx production can cause a decrease in atmospheric methane abundance of up to 80%. Furthermore, the cosmic ray induced HOx molecules react with NOx to produce HNO3, which produces strong HNO3 signals in the theoretical spectra and reduces NOx-induced catalytic destruction of ozone so that more than 25% of the ozone column remains. Hence, an ozone signal remains visible in the theoretical spectrum (albeit with a weaker intensity) when incorporating the new cosmic ray induced NOx and HOx schemes, even for a constantly flaring M-star case. We also find that HNO3 levels may be high enough to be potentially detectable. Since ozone concentrations, which act as the key shield against harmful UV radiation, are affected by cosmic rays via NOx-induced catalytic destruction of ozone, the impact of stellar cosmic rays on surface UV fluxes is also studied.

  20. SCIENCE PARAMETRICS FOR MISSIONS TO SEARCH FOR EARTH-LIKE EXOPLANETS BY DIRECT IMAGING

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Robert A., E-mail: rbrown@stsci.edu [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2015-01-20

    We use N{sub t} , the number of exoplanets observed in time t, as a science metric to study direct-search missions like Terrestrial Planet Finder. In our model, N has 27 parameters, divided into three categories: 2 astronomical, 7 instrumental, and 18 science-operational. For various ''27-vectors'' of those parameters chosen to explore parameter space, we compute design reference missions to estimate N{sub t} . Our treatment includes the recovery of completeness c after a search observation, for revisits, solar and antisolar avoidance, observational overhead, and follow-on spectroscopy. Our baseline 27-vector has aperture D = 16 m, inner working angle IWA = 0.039'', mission time t = 0-5 yr, occurrence probability for Earth-like exoplanets η = 0.2, and typical values for the remaining 23 parameters. For the baseline case, a typical five-year design reference mission has an input catalog of ∼4700 stars with nonzero completeness, ∼1300 unique stars observed in ∼2600 observations, of which ∼1300 are revisits, and it produces N {sub 1} ∼ 50 exoplanets after one year and N {sub 5} ∼ 130 after five years. We explore offsets from the baseline for 10 parameters. We find that N depends strongly on IWA and only weakly on D. It also depends only weakly on zodiacal light for Z < 50 zodis, end-to-end efficiency for h > 0.2, and scattered starlight for ζ < 10{sup –10}. We find that observational overheads, completeness recovery and revisits, solar and antisolar avoidance, and follow-on spectroscopy are all important factors in estimating N.

  1. THE HABITABLE ZONE OF EARTH-LIKE PLANETS WITH DIFFERENT LEVELS OF ATMOSPHERIC PRESSURE

    Energy Technology Data Exchange (ETDEWEB)

    Vladilo, Giovanni; Murante, Giuseppe; Silva, Laura [INAF-Trieste Astronomical Observatory, Trieste (Italy); Provenzale, Antonello [Institute of Atmospheric Sciences and Climate-CNR, Torino (Italy); Ferri, Gaia; Ragazzini, Gregorio, E-mail: vladilo@oats.inaf.it [Department of Physics, University of Trieste, Trieste (Italy)

    2013-04-10

    As a contribution to the study of the habitability of extrasolar planets, we implemented a one-dimensional energy balance model (EBM), the simplest seasonal model of planetary climate, with new prescriptions for most physical quantities. Here we apply our EBM to investigate the surface habitability of planets with an Earth-like atmospheric composition but different levels of surface pressure. The habitability, defined as the mean fraction of the planet's surface on which liquid water could exist, is estimated from the pressure-dependent liquid water temperature range, taking into account seasonal and latitudinal variations of surface temperature. By running several thousands of EBM simulations we generated a map of the habitable zone (HZ) in the plane of the orbital semi-major axis, a, and surface pressure, p, for planets in circular orbits around a Sun-like star. As pressure increases, the HZ becomes broader, with an increase of 0.25 AU in its radial extent from p = 1/3 to 3 bar. At low pressure, the habitability is low and varies with a; at high pressure, the habitability is high and relatively constant inside the HZ. We interpret these results in terms of the pressure dependence of the greenhouse effect, the efficiency of horizontal heat transport, and the extent of the liquid water temperature range. Within the limits discussed in the paper, the results can be extended to planets in eccentric orbits around non-solar-type stars. The main characteristics of the pressure-dependent HZ are modestly affected by variations of planetary properties, particularly at high pressure.

  2. The Stability of Hydrogen-Rich Atmospheres of Earth-Like Planets

    Science.gov (United States)

    Zahnle, Kevin

    2016-01-01

    Understanding hydrogen escape is essential to understanding the limits to habitability, both for liquid water where the Sun is bright, but also to assess the true potential of H2 as a greenhouse gas where the Sun is faint. Hydrogen-rich primary atmospheres of Earth-like planets can result either from gravitational capture of solar nebular gases (with helium), or from impact shock processing of a wide variety of volatile-rich planetesimals (typically accompanied by H2O, CO2, and under the right circumstances, CH4). Most studies of hydrogen escape from planets focus on determining how fast the hydrogen escapes. In general this requires solving hydro- dynamic equations that take into account the acceleration of hydrogen through a critical transonic point and an energy budget that should include radiative heating and cooling, thermal conduction, the work done in lifting the hydrogen against gravity, and the residual heat carried by the hydrogen as it leaves. But for planets from which hydrogen escape is modest or insignificant, the atmosphere can be approximated as hydrostatic, which is much simpler, and for which a relatively full-featured treatment of radiative cooling by embedded molecules, atoms, and ions such as CO2 and H3+ is straightforward. Previous work has overlooked the fact that the H2 molecule is extremely efficient at exciting non-LTE CO2 15 micron emission, and thus that radiative cooling can be markedly more efficient when H2 is abundant. We map out the region of phase space in which terrestrial planets keep hydrogen-rich atmospheres, which is what we actually want to know for habitability. We will use this framework to reassess Tian et al's hypothesis that H2-rich atmospheres may have been rather long-lived on Earth itself. Finally, we will address the empirical observation that rocky planets with thin or negligible atmospheres are rarely or never bigger than 1.6 Earth radii.

  3. Crustal decoupling and mantle dynamics on Venus: implications for Earth-like planets

    Science.gov (United States)

    Ghail, Richard

    2013-04-01

    (intraplate) continental interiors. The higher background heat flux results in a higher incidence of intraplate volcanism than on Earth, in a relatively random distribution that mirrors the near-random distribution of impact craters and results in the observed mean surface age. While these conditions occur on Venus in basaltic crust because of its extreme surface conditions, it offers insight into mantle dynamics beneath Pangaea or an Earth-like planet entirely covered by continental crust. An ESA M-class mission, EnVision, is proposed to undertake InSAR measurements at Venus to determine rates of ground displacement in order to distinguish between these two models.

  4. Coupled thermo-orbital evolution of tidally-evolved Earth-like planets

    Science.gov (United States)

    Behounkova, Marie; Walterova, Michaela; Cadek, Ondrej; Tobie, Gabriel; Choblet, Gael

    2016-10-01

    Progress in detection techniques of exoplanets inspired increasing number of studies focused on their internal dynamics and evolution. The detection methods tend to favor the discovery of short-period exoplanets, that are predicted to get rapidly tidally locked. During the locking process planets despin and a significant amount of tidal heating may contribute to the thermal budget of the planet. Moreover, tidally locked exoplanets exhibit large surface temperature contrasts between sub-stellar and anti-stellar sides due to uneven insolation which influence the convection pattern and cooling of the planet. Here, we will present the evolution of tidally locked Earth-like exoplanets using numerical tool Antigone (Behounkova et al., 2010, 2011) coupling long-term internal evolution, tidal dissipation (taking into account Maxwell or Andrade rheology) and uneven insolation pattern. For constant orbital parameters, we will focus on numerical simulation of the heat transfer in exoEarths for various rheological properties of planet and various values of spin-orbit resonance, semi-major axis, eccentricity and luminosity of star. In the case of effective heat transfer, our results suggest that the melting is mainly observed within the upper part of the mantle for tidal heating lower than 100TW . For tidal heating higher than 100TW, the melt is produced also within the deep part of the mantle and degree-2 convection is enhanced due to tidal heating pattern. For large tidal heating (larger than 1000TW), global melting is observed and temperature field is homogenized due to global melting, the heat transfer is mainly due to melt extraction and advection is suppressed. We will further present first results of coupled orbital-internal evolution of planets without companion using numerical model of orbital evolution with realistic (Maxwell or Andrade) rheology (Walterova et al., in prep). We will concentrate on the capture into the spin-orbit resonance. Special attention will be

  5. Characterising the three-dimensional ozone distribution of a tidally locked Earth-like planet

    Science.gov (United States)

    Proedrou, Elisavet; Hocke, Klemens

    2016-06-01

    We simulate the 3D ozone distribution of a tidally locked Earth-like exoplanet using the high-resolution, 3D chemistry-climate model CESM1(WACCM) and study how the ozone layer of a tidally locked Earth (TLE) (Ω _{TLE}= 1/365 days) differs from that of our present-day Earth (PDE) (Ω _{PDE}= 1/1 day). The middle atmosphere reaches a steady state asymptotically within the first 80 days of the simulation. An upwelling, centred on the subsolar point, is present on the day side while a downwelling, centred on the antisolar point, is present on the night side. In the mesosphere, we find similar global ozone distributions for the TLE and the PDE, with decreased ozone on the day side and enhanced ozone on the night side. In the lower mesosphere, a jet stream transitions into a large-scale vortex around a low-pressure system, located at low latitudes of the TLE night side. In the middle stratosphere, the concentration of odd oxygen is approximately equal to that of the ozone [({O}x) ≈ ({O}3)]. At these altitudes, the lifetime of odd oxygen is ˜16 h and the transport processes significantly contribute to the global distribution of stratospheric ozone. Compared to the PDE, where the strong Coriolis force acts as a mixing barrier between low and high latitudes, the transport processes of the TLE are governed by jet streams variable in the zonal and meridional directions. In the middle stratosphere of the TLE, we find high ozone values on the day side, due to the increased production of atomic oxygen on the day side, where it immediately recombines with molecular oxygen to form ozone. In contrast, the ozone is depleted on the night side, due to changes in the solar radiation distribution and the presence of a downwelling. As a result of the reduced Coriolis force, the tropical and extratropical air masses are well mixed and the global temperature distribution of the TLE stratosphere has smaller horizontal gradients than the PDE. Compared to the PDE, the total ozone column

  6. Extraordinarily High Conductivity of Stretchable Fibers of Polyurethane and Silver Nanoflowers.

    Science.gov (United States)

    Ma, Rujun; Kang, Byeongguk; Cho, Suik; Choi, Minjun; Baik, Seunghyun

    2015-11-24

    Stretchable conductive composites have received considerable attention recently, and they should have high conductivity and mechanical strength. Here we report highly conductive stretchable fibers synthesized by the scalable wet spinning process using flower-shaped silver nanoparticles with nanodisc-shaped petals (Ag nanoflowers) and polyurethane. An extraordinarily high conductivity (41,245 S cm(-1)) was obtained by Ag nanoflowers, which is 2 orders of magnitude greater than that of fibers synthesized using spherical Ag nanoparticles. This was due to the enhanced surface area and vigorous coalescence of nanodisc-shaped petals during the curing process. There was a trade-off relationship between conductivity and stretchability, and the maximum rupture strain was 776%. An analytical model revealed that the enhanced adhesion between Ag nanoflowers and polyurethane provided a high Young's modulus (731.5 MPa) and ultimate strength (39.6 MPa) of the fibers. The fibers exhibited an elastic property after prestretching, and the resistance change of weft-knitted fabric was negligible up to 200% strain. The fibers with extraordinarily high conductivity, stretchability, and mechanical strength may be useful for wearable electronics applications.

  7. Assessing the habitability of planets with Earth-like atmospheres with 1D and 3D climate modeling

    CERN Document Server

    Godolt, M; Kitzmann, D; Kunze, M; Langematz, U; Patzer, A B C; Rauer, H; Stracke, B

    2016-01-01

    The habitable zone (HZ) describes the range of orbital distances around a star where the existence of liquid water on the surface of an Earth-like planet is in principle possible. While 3D climate studies can calculate the water vapor, ice albedo, and cloud feedback self-consistently and therefore allow for a deeper understanding and the identification of relevant climate processes, 1D model studies rely on fewer model assumptions and can be more easily applied to the large parameter space possible for exoplanets. We evaluate the applicability of 1D climate models to estimate the potential habitability of Earth-like exoplanets by comparing our 1D model results to those of 3D climate studies in the literature. We applied a cloud-free 1D radiative-convective climate model to calculate the climate of Earth-like planets around different types of main-sequence stars with varying surface albedo and relative humidity profile. These parameters depend on climate feedbacks that are not treated self-consistently in most...

  8. Extraordinarily long sperm in the socially monogamous cichlid fish Pelvicachromis taeniatus

    Science.gov (United States)

    Thünken, Timo; Bakker, Theo C. M.; Kullmann, Harald

    2007-06-01

    The main function of the spermatozoon is the transfer of the male haploid genome during fertilisation. In animals in general and in fishes in particular, there is huge variation in sperm size. In fishes, sperm size ranges from 13 μm in Mugil cephlus to nearly 100 μm in the channel catfish Ictalurus punctatus. We examined intra-specific variation in sperm morphometry in the socially monogamous cichlid Pelvicachromis taeniatus using scanning electron microscopy. The mean total sperm length of nearly 70 μm was extraordinarily large for cichlids. Furthermore, within-male variation was remarkably high. To our knowledge, P. taeniatus produces the longest cichlid sperm ever documented. Several hypotheses concerning the adaptive significance of these results are presented.

  9. Biomarker response to galactic cosmic ray-induced NOx and the methane greenhouse effect in the atmosphere of an Earth-like planet orbiting an M dwarf star.

    Science.gov (United States)

    Grenfell, John Lee; Griessmeier, Jean-Mathias; Patzer, Beate; Rauer, Heike; Segura, Antigona; Stadelmann, Anja; Stracke, Barbara; Titz, Ruth; Von Paris, Philip

    2007-02-01

    Planets orbiting in the habitable zone of M dwarf stars are subject to high levels of galactic cosmic rays (GCRs), which produce nitrogen oxides (NOx) in Earth-like atmospheres. We investigate to what extent these NO(Mx) species may modify biomarker compounds such as ozone (O3) and nitrous oxide (N2O), as well as related compounds such as water (H2O) (essential for life) and methane (CH4) (which has both abiotic and biotic sources). Our model results suggest that such signals are robust, changing in the M star world atmospheric column due to GCR NOx effects by up to 20% compared to an M star run without GCR effects, and can therefore survive at least the effects of GCRs. We have not, however, investigated stellar cosmic rays here. CH4 levels are about 10 times higher on M star worlds than on Earth because of a lowering in hydroxyl (OH) in response to changes in the ultraviolet. The higher levels of CH4 are less than reported in previous studies. This difference arose partly because we used different biogenic input. For example, we employed 23% lower CH4 fluxes compared to those studies. Unlike on Earth, relatively modest changes in these fluxes can lead to larger changes in the concentrations of biomarker and related species on the M star world. We calculate a CH4 greenhouse heating effect of up to 4K. O3 photochemistry in terms of the smog mechanism and the catalytic loss cycles on the M star world differs considerably compared with that of Earth.

  10. The middle atmospheric circulation of a tidally locked Earth-like planet and the role of the sea surface temperature

    Science.gov (United States)

    Proedrou, Elisavet; Hocke, Klemens; Wurz, Peter

    2016-12-01

    We investigate the influence of the sea surface temperature (SST) changes on the middle atmosphere of a tidally locked Earth-like planet orbiting a G star using the coupled 3D chemistry-climate model CESM1(WACCM). We perform three 90 day simulations. The first simulation is a present-day Earth (PDE) simulation, the second is a simulation of a tidally locked Earth-like planet with a tidally locked aquaplanet sea surface temperature (cold TLE (CLTE)) and the third is a hybrid simulation of a tidally locked Earth-like planet with a present-day Earth sea surface temperature (warm TLE (WTLE)). Our results show that changes in the SST have an influence on the lower stratospheric temperature and the secondary ozone layer. Both atmospheres exhibit a dayside upwelling and a nightside downwelling extending from the surface to the mesosphere. They are also characterised by comparable lower and middle stratospheric horizontal winds and relatively different mesospheric horizontal winds. The temperature of the WTLE atmosphere is altered as a result of the SST changes, compared to the CTLE. Specifically, the WTLE lower tropospheric temperature is increased by 3.7 K on average, due to the absorption of the increased upwelling longwave radiation and the increased sensible and latent heat. The WTLE upper troposphere temperature is decreased by 4 K on average, is adiabatic in nature, and is generated by the increased WTLE upwelling. The WLTE lower stratospheric temperature is increased by 3.8 K on average due to the absorption of the increased upwelling longwave radiation. The lower mesospheric temperature is decreased by 1.13 K on average due to increased mesospheric wave breaking. The upper mesospheric temperature is increased by 4.3 K, and its generation mechanism is currently unknown. Furthermore, the secondary ozone volume mixing ratio is increased by 40.5 %. The occurrence of large-scale vortices and variable jet streams depends, to some extent, on the SST distribution.

  11. Development of a model to compute the extension of life supporting zones for Earth-like exoplanets.

    Science.gov (United States)

    Neubauer, David; Vrtala, Aron; Leitner, Johannes J; Firneis, Maria G; Hitzenberger, Regina

    2011-12-01

    A radiative convective model to calculate the width and the location of the life supporting zone (LSZ) for different, alternative solvents (i.e. other than water) is presented. This model can be applied to the atmospheres of the terrestrial planets in the solar system as well as (hypothetical, Earth-like) terrestrial exoplanets. Cloud droplet formation and growth are investigated using a cloud parcel model. Clouds can be incorporated into the radiative transfer calculations. Test runs for Earth, Mars and Titan show a good agreement of model results with observations.

  12. Assessing the habitability of planets with Earth-like atmospheres with 1D and 3D climate modeling

    Science.gov (United States)

    Godolt, M.; Grenfell, J. L.; Kitzmann, D.; Kunze, M.; Langematz, U.; Patzer, A. B. C.; Rauer, H.; Stracke, B.

    2016-07-01

    Context. The habitable zone (HZ) describes the range of orbital distances around a star where the existence of liquid water on the surface of an Earth-like planet is in principle possible. The applicability of one-dimensional (1D) climate models for the estimation of the HZ boundaries has been questioned by recent three-dimensional (3D) climate studies. While 3D studies can calculate the water vapor, ice albedo, and cloud feedback self-consistently and therefore allow for a deeper understanding and the identification of relevant climate processes, 1D model studies rely on fewer model assumptions and can be more easily applied to the large parameter space possible for extrasolar planets. Aims: We evaluate the applicability of 1D climate models to estimate the potential habitability of Earth-like extrasolar planets by comparing our 1D model results to those of 3D climate studies in the literature. We vary the two important planetary properties, surface albedo and relative humidity, in the 1D model. These depend on climate feedbacks that are not treated self-consistently in most 1D models. Methods: We applied a cloud-free 1D radiative-convective climate model to calculate the climate of Earth-like planets around different types of main-sequence stars with varying surface albedo and relative humidity profile. We compared the results to those of 3D model calculations available in the literature and investigated to what extent the 1D model can approximate the surface temperatures calculated by the 3D models. Results: The 1D parameter study results in a large range of climates possible for an Earth-sized planet with an Earth-like atmosphere and water reservoir at a certain stellar insolation. At some stellar insolations the full spectrum of climate states could be realized, i.e., uninhabitable conditions due to surface temperatures that are too high or too low as well as habitable surface conditions, depending only on the relative humidity and surface albedo assumed. When

  13. Climate of Earth-Like Planets With and Without Ocean Heat Transport Orbiting a Range of M and K Stars

    Science.gov (United States)

    Kiang, N. Y.; Jablonski, Emma R.; Way, Michael J.; Del Genio, Anthony; Roberge, Aki

    2015-01-01

    The mean surface temperature of a planet is now acknowledged as insufficient to surmise its full potential habitability. Advancing our understanding requires exploration with 3D general circulation models (GCMs), which can take into account how gradients and fluxes across a planet's surface influence the distribution of heat, clouds, and the potential for heterogeneous distribution of liquid water. Here we present 3D GCM simulations of the effects of alternative stellar spectra, instellation, model resolution, and ocean heat transport, on the simulated distribution of heat and moisture of an Earth-like planet (ELP).

  14. The O2 A-Band in the Fluxes and Polarization of Starlight Reflected by Earth-Like Exoplanets

    Science.gov (United States)

    Fauchez, Thomas; Rossi, Loic; Stam, Daphne M.

    2017-06-01

    Earth-like, potentially habitable exoplanets are prime targets in the search for extraterrestrial life. Information about their atmospheres and surfaces can be derived by analyzing the light of the parent star reflected by the planet. We investigate the influence of the surface albedo A s, the optical thickness b cloud, the altitude of water clouds, and the mixing ratio of biosignature O2 on the strength of the O2 A-band (around 760 nm) in the flux and polarization spectra of starlight reflected by Earth-like exoplanets. Our computations for horizontally homogeneous planets show that small mixing ratios (η clouds will usually decrease the band depth in flux and the band strength in polarization. However, cloud influence will be strongly dependent on properties such as optical thickness, top altitude, particle phase, coverage fraction, and horizontal distribution. Depending on the surface albedo and cloud properties, different O2 mixing ratios η can give similar absorption-band depths in flux and band strengths in polarization, especially if the clouds have moderate-to-high optical thicknesses. Measuring both the flux and the polarization is essential to reduce the degeneracies, although it will not solve them, especially not for horizontally inhomogeneous planets. Observations at a wide range of phase angles and with a high temporal resolution could help to derive cloud properties and, once those are known, the mixing ratio of O2 or any other absorbing gas.

  15. DETECTABILITY OF EARTH-LIKE PLANETS IN CIRCUMSTELLAR HABITABLE ZONES OF BINARY STAR SYSTEMS WITH SUN-LIKE COMPONENTS

    Energy Technology Data Exchange (ETDEWEB)

    Eggl, Siegfried; Pilat-Lohinger, Elke [University of Vienna, Institute for Astrophysics, Tuerkenschanzstr. 17, A-1180 Vienna (Austria); Haghighipour, Nader, E-mail: siegfried.eggl@univie.ac.at [Institute for Astronomy and NASA Astrobiology Institute, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2013-02-20

    Given the considerable percentage of stars that are members of binaries or stellar multiples in the solar neighborhood, it is expected that many of these binaries host planets, possibly even habitable ones. The discovery of a terrestrial planet in the {alpha} Centauri system supports this notion. Due to the potentially strong gravitational interaction that an Earth-like planet may experience in such systems, classical approaches to determining habitable zones (HZ), especially in close S-type binary systems, can be rather inaccurate. Recent progress in this field, however, allows us to identify regions around the star permitting permanent habitability. While the discovery of {alpha} Cen Bb has shown that terrestrial planets can be detected in solar-type binary stars using current observational facilities, it remains to be shown whether this is also the case for Earth analogs in HZs. We provide analytical expressions for the maximum and rms values of radial velocity and astrometric signals, as well as transit probabilities of terrestrial planets in such systems, showing that the dynamical interaction of the second star with the planet may indeed facilitate the planets' detection. As an example, we discuss the detectability of additional Earth-like planets in the averaged, extended, and permanent HZs around both stars of the {alpha} Centauri system.

  16. Superhabitable Worlds

    CERN Document Server

    Heller, René

    2014-01-01

    To be habitable, a world (planet or moon) does not need to be located in the stellar habitable zone (HZ), and worlds in the HZ are not necessarily habitable. Here, we illustrate how tidal heating can render terrestrial or icy worlds habitable beyond the stellar HZ. Scientists have developed a language that neglects the possible existence of worlds that offer more benign environments to life than Earth does. We call these objects "superhabitable" and discuss in which contexts this term could be used, that is to say, which worlds tend to be more habitable than Earth. In an appendix, we show why the principle of mediocracy cannot be used to logically explain why Earth should be a particularly habitable planet or why other inhabited worlds should be Earth-like. Superhabitable worlds must be considered for future follow-up observations of signs of extraterrestrial life. Considering a range of physical effects, we conclude that they will tend to be slightly older and more massive than Earth and that their host star...

  17. Star Masses and Star-Planet Distances for Earth-like Habitability

    Science.gov (United States)

    Waltham, David

    2017-01-01

    This paper presents statistical estimates for the location and duration of habitable zones (HZs) around stars of different mass. The approach is based upon the assumption that Earth's location, and the Sun's mass, should not be highly atypical of inhabited planets. The results support climate-model-based estimates for the location of the Sun's HZ except models giving a present-day outer-edge beyond 1.64 AU. The statistical approach also demonstrates that there is a habitability issue for stars smaller than 0.65 solar masses since, otherwise, Earth would be an extremely atypical inhabited world. It is difficult to remove this anomaly using the assumption that poor habitability of planets orbiting low-mass stars results from unfavorable radiation regimes either before, or after, their stars enter the main sequence. However, the anomaly is well explained if poor habitability results from tidal locking of planets in the HZs of small stars. The expected host-star mass for planets with intelligent life then has a 95% confidence range of 0.78 M⊙ planets with at least simple life is 0.57 M⊙ < M < 1.64 M⊙.

  18. Star Masses and Star-Planet Distances for Earth-like Habitability.

    Science.gov (United States)

    Waltham, David

    2017-01-01

    This paper presents statistical estimates for the location and duration of habitable zones (HZs) around stars of different mass. The approach is based upon the assumption that Earth's location, and the Sun's mass, should not be highly atypical of inhabited planets. The results support climate-model-based estimates for the location of the Sun's HZ except models giving a present-day outer-edge beyond 1.64 AU. The statistical approach also demonstrates that there is a habitability issue for stars smaller than 0.65 solar masses since, otherwise, Earth would be an extremely atypical inhabited world. It is difficult to remove this anomaly using the assumption that poor habitability of planets orbiting low-mass stars results from unfavorable radiation regimes either before, or after, their stars enter the main sequence. However, the anomaly is well explained if poor habitability results from tidal locking of planets in the HZs of small stars. The expected host-star mass for planets with intelligent life then has a 95% confidence range of 0.78 M⊙ < M < 1.04 M⊙, and the range for planets with at least simple life is 0.57 M⊙ < M < 1.64 M⊙. Key Words: Habitability-Habitable zone-Anthropic-Red dwarfs-Initial mass function. Astrobiology 17, 61-77.

  19. Star Masses and Star-Planet Distances for Earth-like Habitability

    Science.gov (United States)

    2017-01-01

    Abstract This paper presents statistical estimates for the location and duration of habitable zones (HZs) around stars of different mass. The approach is based upon the assumption that Earth's location, and the Sun's mass, should not be highly atypical of inhabited planets. The results support climate-model-based estimates for the location of the Sun's HZ except models giving a present-day outer-edge beyond 1.64 AU. The statistical approach also demonstrates that there is a habitability issue for stars smaller than 0.65 solar masses since, otherwise, Earth would be an extremely atypical inhabited world. It is difficult to remove this anomaly using the assumption that poor habitability of planets orbiting low-mass stars results from unfavorable radiation regimes either before, or after, their stars enter the main sequence. However, the anomaly is well explained if poor habitability results from tidal locking of planets in the HZs of small stars. The expected host-star mass for planets with intelligent life then has a 95% confidence range of 0.78 M⊙ planets with at least simple life is 0.57 M⊙ < M < 1.64 M⊙. Key Words: Habitability—Habitable zone—Anthropic—Red dwarfs—Initial mass function. Astrobiology 17, 61–77. PMID:28103107

  20. The Universe Going Green: Extraordinarily Strong [OIII]5007 in Typical Dwarf Galaxies at z~3

    Science.gov (United States)

    Malkan, Matthew Arnold; Cohen, Daniel

    2017-01-01

    We constructed the average SEDs of U-dropout galaxies in the Subaru Deep Field. This sample contains more than 5000 Lyman-break galaxies at z~3. Their average near- and mid-IR colors were obtained by stacking JHK and IRAC imaging, in bins of stellar mass. At the lowest mass bins an increasingly strong excess flux is seen in the K filter. This excess can reach 1 magnitude in the broadband filter, and we attribute it to strong \\OIII $\\lambda{5007}$ line emission. The equivalent width is extraordinarily high, reaching almost 1000\\Ang\\ for the average z=3 galaxy at an i magnitude of 27. Such extreme [OIII] emission is very rare in the current epoch, only seen in a handful of metal-deficient dwarf starbursts sometimes referred to as ''Green Peas". In contrast, extreme [OIII]--strong enough to dominate the entire broad-band SED--was evidently the norm for faint galaxies at high redshift. We present evidence that these small but numerous galaxies were primarily responsible for the reionization of the Universe.

  1. Swansong Biospheres: The biosignatures of inhabited earth-like planets nearing the end of their habitable lifetimes

    Science.gov (United States)

    O'Malley-James, Jack T.; Greaves, Jane S.; Raven, John A.; Cockell, Charles S.

    2014-01-01

    The biosignatures of life on Earth are not fixed, but change with time as environmental conditions change and life living within those environments adapts to the new conditions. A latitude-based climate model, incorporating orbital parameter variations, was used to simulate conditions on the far-future Earth as the Sun enters the late main sequence. Over time, conditions increasingly favour a unicellular microbial biosphere, which can persist for a maximum of 2.8 Gyr from present. The biosignature changes associated with the likely biosphere changes are evaluated using a biosphere-atmosphere gas exchange model and their detectability is discussed. As future Earth-like exoplanet discoveries could be habitable planets nearing the end of their habitable lifetimes, this helps inform the search for the signatures of life beyond Earth

  2. The Catalog of Earth-Like Exoplanet Survey TArgets (CELESTA): A Database of Habitable Zones around Nearby Stars

    CERN Document Server

    Chandler, Colin Orion; Kane, Stephen R

    2015-01-01

    Locating planets in circumstellar Habitable Zones is a priority for many exoplanet surveys. Space-based and ground-based surveys alike require robust toolsets to aid in target selection and mission planning. We present the Catalog of Earth-Like Exoplanet Survey Targets (CELESTA), a database of Habitable Zones around 36,000 nearby stars. We calculated stellar parameters, including effective temperatures, masses, and radii, and we quantified the orbital distances and periods corresponding to the circumstellar Habitable Zones. We gauged the accuracy of our predictions by contrasting CELESTA's computed parameters to observational data. We ascertain a potential return on investment by computing the number of Habitable Zones probed for a given survey duration. A versatile framework for extending the functionality of CELESTA into the future enables ongoing comparisons to new observations, and recalculations when updates to Habitable Zone models, stellar temperatures, or parallax data become available. We expect to u...

  3. Earth-like aqueous debris-flow activity on Mars at high orbital obliquity in the last million years.

    Science.gov (United States)

    de Haas, T; Hauber, E; Conway, S J; van Steijn, H; Johnsson, A; Kleinhans, M G

    2015-06-23

    Liquid water is currently extremely rare on Mars, but was more abundant during periods of high obliquity in the last few millions of years. This is testified by the widespread occurrence of mid-latitude gullies: small catchment-fan systems. However, there are no direct estimates of the amount and frequency of liquid water generation during these periods. Here we determine debris-flow size, frequency and associated water volumes in Istok crater, and show that debris flows occurred at Earth-like frequencies during high-obliquity periods in the last million years on Mars. Results further imply that local accumulations of snow/ice within gullies were much more voluminous than currently predicted; melting must have yielded centimetres of liquid water in catchments; and recent aqueous activity in some mid-latitude craters was much more frequent than previously anticipated.

  4. Properties of an Earth-like planet orbiting a Sun-like star: Earth observed by the EPOXI mission.

    Science.gov (United States)

    Livengood, Timothy A; Deming, L Drake; A'hearn, Michael F; Charbonneau, David; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Meadows, Victoria S; Robinson, Tyler D; Seager, Sara; Wellnitz, Dennis D

    2011-11-01

    NASA's EPOXI mission observed the disc-integrated Earth and Moon to test techniques for reconnoitering extrasolar terrestrial planets, using the Deep Impact flyby spacecraft to observe Earth at the beginning and end of Northern Hemisphere spring, 2008, from a range of ∼1/6 to 1/3 AU. These observations furnish high-precision and high-cadence empirical photometry and spectroscopy of Earth, suitable as "ground truth" for numerically simulating realistic observational scenarios for an Earth-like exoplanet with finite signal-to-noise ratio. Earth was observed at near-equatorial sub-spacecraft latitude on 18-19 March, 28-29 May, and 4-5 June (UT), in the range of 372-4540 nm wavelength with low visible resolving power (λ/Δλ=5-13) and moderate IR resolving power (λ/Δλ=215-730). Spectrophotometry in seven filters yields light curves at ∼372-948 nm filter-averaged wavelength, modulated by Earth's rotation with peak-to-peak amplitude of ≤20%. The spatially resolved Sun glint is a minor contributor to disc-integrated reflectance. Spectroscopy at 1100-4540 nm reveals gaseous water and carbon dioxide, with minor features of molecular oxygen, methane, and nitrous oxide. One-day changes in global cloud cover resulted in differences between the light curve beginning and end of ≤5%. The light curve of a lunar transit of Earth on 29 May is color-dependent due to the Moon's red spectrum partially occulting Earth's relatively blue spectrum. The "vegetation red edge" spectral contrast observed between two long-wavelength visible/near-IR bands is ambiguous, not clearly distinguishing between the verdant Earth diluted by cloud cover versus the desolate mineral regolith of the Moon. Spectrophotometry in at least one other comparison band at short wavelength is required to distinguish between Earth-like and Moon-like surfaces in reconnaissance observations. However, measurements at 850 nm alone, the high-reflectance side of the red edge, could be sufficient to

  5. On the protection of extrasolar Earth-like planets around K/M stars against galactic cosmic rays

    CERN Document Server

    Grießmeier, J M; Grenfell, J L; Lammer, H; Motschmann, U; 10.1016/j.icarus.2008.09.015

    2009-01-01

    Previous studies have shown that extrasolar Earth-like planets in close-in habitable zones around M-stars are weakly protected against galactic cosmic rays (GCRs), leading to a strongly increased particle flux to the top of the planetary atmosphere. Two main effects were held responsible for the weak shielding of such an exoplanet: (a) For a close-in planet, the planetary magnetic moment is strongly reduced by tidal locking. Therefore, such a close-in extrasolar planet is not protected by an extended magnetosphere. (b) The small orbital distance of the planet exposes it to a much denser stellar wind than that prevailing at larger orbital distances. This dense stellar wind leads to additional compression of the magnetosphere, which can further reduce the shielding efficiency against GCRs. In this work, we analyse and compare the effect of (a) and (b), showing that the stellar wind variation with orbital distance has little influence on the cosmic ray shielding. Instead, the weak shielding of M star planets can...

  6. The runaway Greenhouse revisited: it's "theoretically possible for an Earth-like planet at 1 AU", plus implications for more diverse planets

    Science.gov (United States)

    Goldblatt, C.; Zahnle, K. J.; Crisp, D.; Robinson, T. D.

    2013-12-01

    For water-vapour rich atmospheres, there is an asymptotic limit on thermal emission to space. If more sunlight is absorbed than this limit, energy balance is no longer possible and runaway heating occurs, evaporating the ocean and sterilizing the planet en route. Here, we present recently published work (Goldblatt et al., 2013) which was the first full re-evaluation of the problem since classic 1980's era work (e.g. Watson et al., 1984; Abe & Matsui, 1988; Kasting, 1988). With modern molecular absorption databases and a line-by-line resolution model, we find that the thermal limit is lower than previous estimates (282Wm-2, down from 310Wm-2) and that much more sunlight is absorbed by a steam atmosphere (294Wm-2, up from 222Wm-2). The immediate implication is that a cloud-free moist atmosphere on Earth would cause a runaway greenhouse. Triggering it would simply be a matter of sufficient heating, with around 30,000ppmv being sufficient in our most Earth-like model. This is substantially different than previous calculations, where weak solar absorption meant that a higher solar flux was required. Our published calculations are for the limit of clear-skies; any clouds would reduce both the thermal radiation emitted and the solar radiation absorbed, so clouds could make the runaway greenhouse either more or less likely. It can be shown that and excess of cloud reflection over cloud greenhouse is required to maintain temperate climate on Earth today - but how clouds will change in a warming atmosphere is far from clear. Work in progress (and hopefully ready by December!) on cloudy runaway greenhouse models will hopefully constrain this better. Wider implications for planetary stability will also be discussed. For example, water-world planets, with minimal background gas in the atmosphere may be highly susceptible to runaway greenhouses (heating Europa might take it directly from a snowball to a runaway). High CO2 levels after previous Snowball Earth events did not

  7. Origin and Ubiquity of Short-Period Earth-like Planets: Evidence for the Sequential-Accretion Theory of Planet Formation

    OpenAIRE

    Zhou, J. L.; Aarseth, S. J.; Lin, D. N. C.; Nagasawa, M.

    2005-01-01

    The formation of gas giant planets is assumed to be preceded by the emergence of solid cores in the conventional sequential-accretion paradigm. This hypothesis implies that the presence of earth-like planets can be inferred from the detection of gas giants. A similar prediction cannot be made with the gravitational instability (hereafter GI) model which assumes that gas giants (hereafter giants) formed from the collapse of gas fragments analogous to their host stars. We propose an observation...

  8. The sustainability of habitability on terrestrial planets: Insights, questions, and needed measurements from Mars for understanding the evolution of Earth-like worlds

    Science.gov (United States)

    Ehlmann, B. L.; Anderson, F. S.; Andrews-Hanna, J.; Catling, D. C.; Christensen, P. R.; Cohen, B. A.; Dressing, C. D.; Edwards, C. S.; Elkins-Tanton, L. T.; Farley, K. A.; Fassett, C. I.; Fischer, W. W.; Fraeman, A. A.; Golombek, M. P.; Hamilton, V. E.; Hayes, A. G.; Herd, C. D. K.; Horgan, B.; Hu, R.; Jakosky, B. M.; Johnson, J. R.; Kasting, J. F.; Kerber, L.; Kinch, K. M.; Kite, E. S.; Knutson, H. A.; Lunine, J. I.; Mahaffy, P. R.; Mangold, N.; McCubbin, F. M.; Mustard, J. F.; Niles, P. B.; Quantin-Nataf, C.; Rice, M. S.; Stack, K. M.; Stevenson, D. J.; Stewart, S. T.; Toplis, M. J.; Usui, T.; Weiss, B. P.; Werner, S. C.; Wordsworth, R. D.; Wray, J. J.; Yingst, R. A.; Yung, Y. L.; Zahnle, K. J.

    2016-10-01

    What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar system's longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to understanding the factors driving the divergent evolutionary paths of the Earth, Venus, and thousands of small rocky extrasolar planets yet to be discovered.

  9. The Sustainability of Habitability on Terrestrial Planets: Insights, Questions, and Needed Measurements from Mars for Understanding the Evolution of Earth-Like Worlds

    Science.gov (United States)

    Ehlmann, B. L.; Anderson, F. S.; Andrews-Hanna, J.; Catling, D. C.; Christensen, P. R.; Cohen, B. A.; Dressing, C. D.; Edwards, C. S.; Elkins-Tanton, L. T.; Farley, K. A.; hide

    2016-01-01

    What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar systems longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to understanding the factors driving the divergent evolutionary paths of the Earth, Venus, and thousands of small rocky extra solar planets yet to be discovered.

  10. Pathways to Earth-Like Atmospheres. Extreme Ultraviolet (EUV)-Powered Escape of Hydrogen-Rich Protoatmospheres

    Science.gov (United States)

    Lammer, Helmut; Kislyakova, K. G.; Odert, P.; Leitzinger, M.; Schwarz, R.; Pilat-Lohinger, E.; Kulikov, Yu. N.; Khodachenko, M. L.; Güdel, M.; Hanslmeier, A.

    2011-12-01

    We discuss the evolution of the atmosphere of early Earth and of terrestrial exoplanets which may be capable of sustaining liquid water oceans and continents where life may originate. The formation age of a terrestrial planet, its mass and size, as well as the lifetime in the EUV-saturated early phase of its host star play a significant role in its atmosphere evolution. We show that planets even in orbits within the habitable zone of their host stars might not lose nebular- or catastrophically outgassed initial protoatmospheres completely and could end up as water worlds with CO2 and hydrogen- or oxygen-rich upper atmospheres. If an atmosphere of a terrestrial planet evolves to an N2-rich atmosphere too early in its lifetime, the atmosphere may be lost. We show that the initial conditions set up by the formation of a terrestrial planet and by the evolution of the host star's EUV and plasma environment are very important factors owing to which a planet may evolve to a habitable world. Finally we present a method for studying the discussed atmosphere evolution hypotheses by future UV transit observations of terrestrial exoplanets.

  11. Extraordinarily soft, medium-hard and hard Indian wheat varieties: Composition, protein profile, dough and baking properties.

    Science.gov (United States)

    Katyal, Mehak; Singh, Narpinder; Virdi, Amardeep Singh; Kaur, Amritpal; Chopra, Nidhi; Ahlawat, Arvind Kumar; Singh, Anju Mahendru

    2017-10-01

    Hard wheat (HW), medium-hard wheat (MHW) and extraordinarily soft wheat (Ex-SW) varieties with grain hardness index (GHI) of 83 to 95, 72 to 80, 17 to 29 were evaluated for pasting, protein molecular weight (MW) distribution, dough rheology and baking properties. Flours from varieties with higher GHI had more protein content, ash content and paste viscosities. Ex-SW had more glutenins proportion as compared to HW and MHW. Flours from Ex-SW varieties showed lower NaSRC, WA and mixographic parameters as compared to HW and MHW. Dough from flours milled from Ex-SW had higher Intermolecular-β-sheets (IM-β-sheets) than those from MHW and HW. Muffins volume increased with decrease in GHI, Ex-SW varieties had more muffin volume and less air space. The accumulation of polypeptides (PPs) varied significantly in different varieties. Ex-SW variety (QBP12-10) showed accumulation of 98, 90, 81 and 79kDa PPs, which was unique and was different from other varieties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Future snow? A spatial-probabilistic assessment of the extraordinarily low snowpacks of 2014 and 2015 in the Oregon Cascades

    Science.gov (United States)

    Sproles, Eric A.; Roth, Travis R.; Nolin, Anne W.

    2017-02-01

    In the Pacific Northwest, USA, the extraordinarily low snowpacks of winters 2013-2014 and 2014-2015 stressed regional water resources and the social-environmental system. We introduce two new approaches to better understand how seasonal snow water storage during these two winters would compare to snow water storage under warmer climate conditions. The first approach calculates a spatial-probabilistic metric representing the likelihood that the snow water storage of 2013-2014 and 2014-2015 would occur under +2 °C perturbed climate conditions. We computed snow water storage (basin-wide and across elevations) and the ratio of snow water equivalent to cumulative precipitation (across elevations) for the McKenzie River basin (3041 km2), a major tributary to the Willamette River in Oregon, USA. We applied these computations to calculate the occurrence probability for similarly low snow water storage under climate warming. Results suggest that, relative to +2 °C conditions, basin-wide snow water storage during winter 2013-2014 would be above average, while that of winter 2014-2015 would be far below average. Snow water storage on 1 April corresponds to a 42 % (2013-2014) and 92 % (2014-2015) probability of being met or exceeded in any given year. The second approach introduces the concept of snow analogs to improve the anticipatory capacity of climate change impacts on snow-derived water resources. The use of a spatial-probabilistic approach and snow analogs provide new methods of assessing basin-wide snow water storage in a non-stationary climate and are readily applicable in other snow-dominated watersheds.

  13. Sensitivity of Biosignatures on Earth-like Planets orbiting in the Habitable Zone of Cool M-Dwarf Stars to varying Stellar UV Radiation and Surface Biomass Emissions

    CERN Document Server

    Grenfell, John Lee; von Paris, Philip; Godolt, Mareike; Rauer, Heike

    2015-01-01

    We find that variations in the UV emissions of cool M-dwarf stars have a potentially large impact upon atmospheric biosignatures in simulations of Earth-like exoplanets i.e. planets with Earths development, and biomass and a molecular nitrogen-oxygen dominated atmosphere. Starting with an assumed black-body stellar emission for an M7 class dwarf star, the stellar UV irradiation was increased stepwise and the resulting climate-photochemical response of the planetary atmosphere was calculated. Results suggest a Goldilocks effect with respect to the spectral detection of ozone. At weak UV levels, the ozone column was weak (due to weaker production from the Chapman mechanism) hence its spectral detection was challenging. At strong UV levels, ozone formation is stronger but its associated stratospheric heating leads to a weakening in temperature gradients between the stratosphere and troposphere, which results in weakened spectral bands. Also, increased UV levels can lead to enhanced abundances of hydrogen oxides ...

  14. Response of Atmospheric Biomarkers to NOx-induced Photochemistry Generated by Stellar Cosmic Rays for Earth-like Planets in the Habitable Zone of M-Dwarf Stars

    CERN Document Server

    Grenfell, John Lee; von Paris, Philip; Patzer, Beate; Lammer, Helmut; Stracke, Barbara; Gebauer, Stefanie; Schreier, Franz; Rauer, Heike

    2015-01-01

    Understanding whether M-dwarf stars may host habitable planets with Earth-like atmospheres and biospheres is a major goal in exoplanet research. If such planets exist, the question remains as to whether they could be identified via spectral signatures of biomarkers. Such planets may be exposed to extreme intensities of cosmic rays that could perturb their atmospheric photochemistry. Here, we consider stellar activity of M-dwarfs ranging from quiet up to strong flaring conditions and investigate one particular effect upon biomarkers, namely, the ability of secondary electrons caused by stellar cosmic rays to break up atmospheric molecular nitrogen (N2), which leads to production of nitrogen oxides in the planetary atmosphere, hence affecting biomarkers such as ozone. We apply a stationary model, that is, without a time-dependence, hence we are calculating the limiting case where the atmospheric chemistry response time of the biomarkers is assumed to be slow and remains constant compared with rapid forcing by t...

  15. Apodized Pupil Lyot Coronagraphs for Arbitrary Apertures. V. Hybrid Shaped Pupil Designs for Imaging Earth-like planets with Future Space Observatories

    Science.gov (United States)

    N'Diaye, Mamadou; Soummer, Rémi; Pueyo, Laurent; Carlotti, Alexis; Stark, Christopher C.; Perrin, Marshall D.

    2016-02-01

    We introduce a new class of solutions for Apodized Pupil Lyot Coronagraphs (APLC) with segmented aperture telescopes to remove broadband diffracted light from a star with a contrast level of 1010. These new coronagraphs provide a key advance to enabling direct imaging and spectroscopy of Earth twins with future large space missions. Building on shaped pupil (SP) apodization optimizations, our approach enables two-dimensional optimizations of the system to address any aperture features such as central obstruction, support structures, or segment gaps. We illustrate the technique with a design that could reach a 1010 contrast level at 34 mas for a 12 m segmented telescope over a 10% bandpass centered at a wavelength of {λ }0 = 500 nm. These designs can be optimized specifically for the presence of a resolved star and, in our example, for stellar angular size up to 1.1 mas. This would allow one to probe the vicinity of Sun-like stars located beyond 4.4 pc, therefore, fully retiring this concern. If the fraction of stars with Earth-like planets is {η }\\oplus =0.1, with 18% throughput, assuming a perfect, stable wavefront and considering photon noise only, 12.5 exo-Earth candidates could be detected around nearby stars with this design and a 12 m space telescope during a five-year mission with two years dedicated to exo-Earth detection (one total year of exposure time and another year of overheads). Our new hybrid APLC/SP solutions represent the first numerical solution of a coronagraph based on existing mask technologies and compatible with segmented apertures, and that can provide contrast compatible with detecting and studying Earth-like planets around nearby stars. They represent an important step forward toward enabling these science goals with future large space missions.

  16. Assessing the Chemistry of Tidally Locked Earth-like Planets around M-type Stars Using a 3D Coupled Chemistry-Climate Model (CESM/WACCM)

    Science.gov (United States)

    Lanzano, Alexander

    2016-10-01

    Given recent discoveries there is a very real potential for tidally-locked Earth-like planets to exist orbiting M stars. To determine whether these planets may be habitable it is necessary to understand the nature of their atmospheres. In our investigation we simulate the evolution of present-day Earth while placed in tidally-locked orbit (meaning the same side of the planet always faces the star) around an M dwarf star. We are particularly interested in the evolution of the planet's ozone layer and whether it will shield the planet, and therefore life, from harmful radiation.To accomplish the above objectives we use a state-of-the-art 3-D terrestrial model, the Whole Atmosphere Community Climate Model (WACCM), which fully couples chemistry and climate, and therefore allows self-consistent simulations of atmospheric constituents and their effects on a planet's climate, surface radiation and thus habitability. Preliminary results show that this model is stable and that a tidally-locked Earth is protected from harmful UV radiation produced by G stars. The next step shall be to adapt this model for an M star by including its UV and visible spectrum.This investigation will both provide an insight into the potential for habitable exoplanets and further define the nature of the habitable zones for M class stars. We will also be able to narrow the definition of the habitable zones around distant stars, which will help us identify these planets in the future. Furthermore, this project will allow for a more thorough analysis of data from past and future exoplanet observing missions by defining the atmospheric composition of Earth-like planets around a variety of types of stars.

  17. The Effect of a Strong Stellar Flare on the Atmospheric Chemistry of an Earth-like Planet Orbiting an M dwarf

    CERN Document Server

    Segura, Antígona; Meadows, Victoria; Kasting, James; Hawley, Suzanne

    2010-01-01

    Main sequence M stars pose an interesting problem for astrobiology: their abundance in our galaxy makes them likely targets in the hunt for habitable planets, but their strong chromospheric activity produces high energy radiation and charged particles that may be detrimental to life. We studied the impact of the 1985 April 12 flare from the M dwarf, AD Leonis (AD Leo), simulating the effects from both UV radiation and protons on the atmospheric chemistry of a hypothetical, Earth-like planet located within its habitable zone. Based on observations of solar proton events and the Neupert effect we estimated a proton flux associated with the flare of $5.9\\times 10^{8}$ protons cm$^{-2}$ sr$^{-1}$ s$^{-1}$ for particles with energies >10 MeV. Then we calculated the abundance of nitrogen oxides produced by the flare by scaling the production of these compounds during a large solar proton event called the "Carrington event". The simulations were performed using a 1-D photochemical model coupled to a 1-D radiative/co...

  18. Spectral features of Earth-like planets and their detectability at different orbital distances around F, G, and K-type stars

    CERN Document Server

    Hedelt, Pascal; Godolt, Mareike; Gebauer, Stefanie; Grenfell, John Lee; Rauer, Heike; Schreier, Franz; Selsis, Franck; Trautmann, Thomas

    2013-01-01

    We investigate the spectral appearance of Earth-like exoplanets in the HZ of different main sequence stars at different orbital distances. We furthermore discuss for which of these scenarios biomarker absorption bands may be detected during primary or secondary transit with near-future telescopes and instruments.We analyze the spectra taking into account different filter bandpasses of two photometric instruments planned to be mounted to the JWST. We analyze in which filters and for which scenarios molecular absorption bands are detectable when using the space-borne JWST or the ground-based telescope E-ELT. Absorption bands of CO2, H2O, CH4 and O3 are clearly visible in high-resolution spectra as well as in the filters of photometric instruments. However, only during primary eclipse bands of CO2, H2O and O3 are detectable for all scenarios when using photometric instruments and an E-ELT telescope setup. CH4 is only detectable at the outer HZ of the K star since here the atmospheric modeling results in very hig...

  19. Origin and Ubiquity of Short-Period Earth-like Planets: Evidence for the Sequential-Accretion Theory of Planet Formation

    CERN Document Server

    Zhou, J L; Lin, D N C; Nagasawa, M

    2005-01-01

    The formation of gas giant planets is assumed to be preceded by the emergence of solid cores in the conventional sequential-accretion paradigm. This hypothesis implies that the presence of earth-like planets can be inferred from the detection of gas giants. A similar prediction cannot be made with the gravitational instability (hereafter GI) model which assumes that gas giants (hereafter giants) formed from the collapse of gas fragments analogous to their host stars. We propose an observational test for the determination of the dominant planet-formation channel. Based on the sequential-accretion (hereafter SA) model, we identify several potential avenues which may lead to the prolific formation of a population of close-in earth-mass ($M_\\oplus$) planets (hereafter close-in earths) around stars with 1) short-period or 2) solitary eccentric giants and 3) systems which contain intermediate-period resonant giants. In contrast, these close-in earths are not expected to form in systems where giants originated rapid...

  20. Never Marry a Woman with Big Feet : Women in Proverbs from Around the World

    NARCIS (Netherlands)

    Schipper, Mineke

    2006-01-01

    Winner of the Dutch 2005 Eureka! prize for best non-fiction title The jury about the book: "A revealing and at the same time extraordinarily funny book" In cultures all over the globe, sex and gender issues have been expressed in proverbs, the world's smallest literary genre. This irresistible book

  1. Abiotic production of nitrous oxide by lightning. Implications for a false positive identification of life on Earth-Like Planets around quiescent M Dwarfs

    Science.gov (United States)

    Navarro, Karina F.; Navarro-Gonzalez, Rafael; McKay, Christopher P.

    Nitrous oxide (N _{2}O) is uniformly mixed in the troposphere with a concentration of about 310 ppb but disappears in the stratosphere (Prinn et al., 1990); N _{2}O is mostly emitted at a rate of 1x10 (13) g yr (-1) as a byproduct of microbial activity in soils and in the ocean by two processes: a) denitrification (reduction of nitrate and nitrite), and b) nitrification (oxidation of ammonia) (Maag and Vinther, 1996). The abiotic emission of N _{2}O in the contemporaneous Earth is small, mostly arising from lightning activity (2x10 (9) g yr (-1) , Hill et al., 1984) and by reduction of nitrite by Fe(II)-minerals in soils in Antarctica (Samarkin et al., 2010). Since N _{2}O has absorption bands in the mid-IR (7.8, 8.5, and 17 mumm) that makes it detectable by remote sensing (Topfer et al., 1997; Des Marais et al., 2002), it has been suggested as a potential biosignature in the search for life in extrasolar planets (Churchill and Kasting, 2000). However, the minimum required concentration for positive identification is 10,000 ppb with missions like Terrestrial Planet Finder and Darwin (Churchill and Kasting, 2000). Therefore, it is not a suitable biomarker for extrasolar Earth-like planets orbiting stars similar to the Sun. Because N _{2}O is protected in the troposphere from UV photolysis by the stratospheric ozone layer, its concentration would decrease with decreasing oxygen (O _{2}) concentrations, if the biological source strength remains constant (Kasting and Donahue, 1980). For a primitive Earth-like (Hadean) atmosphere dominated by CO _{2}, and no free O _{2}, the expected N _{2}O concentration would be about 3 ppb with the current microbial N _{2}O flux (Churchill and Kasting, 2000). The resulting N _{2}O spectral signature of this atmosphere would be undetectable unless the N _{2}O microbial flux would be 10 (4) greater than its present value (Churchill and Kasting, 2000). Since this flux is unlikely, it is impossible to use it as a biomarker in anoxic CO

  2. A new class of fluorescent boronic acids that have extraordinarily high affinities for diols in aqueous solution at physiological pH.

    Science.gov (United States)

    Cheng, Yunfeng; Ni, Nanting; Yang, Wenqian; Wang, Binghe

    2010-12-03

    The boronic acid group is an important recognition moiety for sensor design. Herein, we report a series of isoquinolinylboronic acids that have extraordinarily high affinities for diol-containing compounds at physiological pH. In addition, 5- and 8-isoquinolinylboronic acids also showed fairly high binding affinities towards D-glucose (K(a)=42 and 46 M(-1), respectively). For the first time, weak but encouraging binding of cis-cyclohexanediol was found for these boronic acids. Such binding was coupled with significant fluorescence changes. Furthermore, 4- and 6-isoquinolinylboronic acids also showed the ability to complex methyl α-D-glucopyranose (K(a)=3 and 2 M(-1), respectively).

  3. 类地行星偏振特性研究∗%Study of Polarimetries of the Earth-like Exoplanet

    Institute of Scientific and Technical Information of China (English)

    宋伟; 屈中权

    2016-01-01

    相比于其他探测手段,行星的偏振探测能够提供更多有关行星表面以及大气的细节信息,而地球的偏振测量则有助于寻找系外类地行星以及对其大气和表面特征的鉴定.将地球看成一颗与其寄主星(太阳)可分辨但其自身圆面不可分辨的行星来研究其在太阳照射后辐射进入太空的偏振特性.采用PARASOL的670 nm (662.4 nm∼677.4 nm)波段的观测结果,得到不同地表类型和云层的偏振度和反照率随散射角和相对方位角的变化,然后根据辐射偏振的Stokes参量可叠加特性,求得在90◦散射角下,地球整体辐射的偏振度随自转的变化.结果发现:影响地球偏振的最大因素是海洋和云层,地球偏振度可以在18.6%到49%之间变化.由于气候变化导致的云层分布的随机性使得地球偏振度的变化具有快速多变的特点.揭示的这一特征有助于辨别系外类地行星.%Compared with other diagnostic techniques, the planetary polarimetry becomes more efficient to probe the details about the surface features of an exoplanet, and especially the polarimetry of our planet, the Earth, is useful to search for the Earth-like exoplanet. In this paper, the Earth is treated as a planet resolvable from its host star but its disk is unresolved. The data from the polarimeter boarding French satellite PARASOL are used to get the polarimetric results of 5 surface features as well as cloud within the band of 662.4–677.4 nm. The results are expressed in the curves which reflect the variations of linear polarization degree and albedo with the scattering and azimuth angles, respectively. Under the special case that the scattering angle is set to be 90 degrees, the polarization curves of the Earth in a rotation period are obtained. It is found that the polarization degree is mainly influenced by the ocean as well as the cloud, ranging from 18.6%to 49%. And due to the rapid climate change on the Earth, the

  4. Remote life-detection criteria, habitable zone boundaries, and the frequency of Earth-like planets around M and late K stars.

    Science.gov (United States)

    Kasting, James F; Kopparapu, Ravikumar; Ramirez, Ramses M; Harman, Chester E

    2014-09-02

    The habitable zone (HZ) around a star is typically defined as the region where a rocky planet can maintain liquid water on its surface. That definition is appropriate, because this allows for the possibility that carbon-based, photosynthetic life exists on the planet in sufficient abundance to modify the planet's atmosphere in a way that might be remotely detected. Exactly what conditions are needed, however, to maintain liquid water remains a topic for debate. In the past, modelers have restricted themselves to water-rich planets with CO2 and H2O as the only important greenhouse gases. More recently, some researchers have suggested broadening the definition to include arid, "Dune" planets on the inner edge and planets with captured H2 atmospheres on the outer edge, thereby greatly increasing the HZ width. Such planets could exist, but we demonstrate that an inner edge limit of 0.59 AU or less is physically unrealistic. We further argue that conservative HZ definitions should be used for designing future space-based telescopes, but that optimistic definitions may be useful in interpreting the data from such missions. In terms of effective solar flux, S(eff), the recently recalculated HZ boundaries are: recent Venus--1.78; runaway greenhouse--1.04; moist greenhouse--1.01; maximum greenhouse--0.35; and early Mars--0.32. Based on a combination of different HZ definitions, the frequency of potentially Earth-like planets around late K and M stars observed by Kepler is in the range of 0.4-0.5.

  5. Remote life-detection criteria, habitable zone boundaries, and the frequency of Earth-like planets around M and late K stars

    Science.gov (United States)

    Kasting, James F.; Kopparapu, Ravikumar; Ramirez, Ramses M.; Harman, Chester E.

    2014-09-01

    The habitable zone (HZ) around a star is typically defined as the region where a rocky planet can maintain liquid water on its surface. That definition is appropriate, because this allows for the possibility that carbon-based, photosynthetic life exists on the planet in sufficient abundance to modify the planet's atmosphere in a way that might be remotely detected. Exactly what conditions are needed, however, to maintain liquid water remains a topic for debate. In the past, modelers have restricted themselves to water-rich planets with CO2 and H2O as the only important greenhouse gases. More recently, some researchers have suggested broadening the definition to include arid, "Dune" planets on the inner edge and planets with captured H2 atmospheres on the outer edge, thereby greatly increasing the HZ width. Such planets could exist, but we demonstrate that an inner edge limit of 0.59 AU or less is physically unrealistic. We further argue that conservative HZ definitions should be used for designing future space-based telescopes, but that optimistic definitions may be useful in interpreting the data from such missions. In terms of effective solar flux, Seff, the recently recalculated HZ boundaries are: recent Venus-1.78; runaway greenhouse-1.04; moist greenhouse-1.01; maximum greenhouse-0.35; and early Mars-0.32. Based on a combination of different HZ definitions, the frequency of potentially Earth-like planets around late K and M stars observed by Kepler is in the range of 0.4-0.5.

  6. The effect of a strong stellar flare on the atmospheric chemistry of an earth-like planet orbiting an M dwarf.

    Science.gov (United States)

    Segura, Antígona; Walkowicz, Lucianne M; Meadows, Victoria; Kasting, James; Hawley, Suzanne

    2010-09-01

    Main sequence M stars pose an interesting problem for astrobiology: their abundance in our galaxy makes them likely targets in the hunt for habitable planets, but their strong chromospheric activity produces high-energy radiation and charged particles that may be detrimental to life. We studied the impact of the 1985 April 12 flare from the M dwarf AD Leonis (AD Leo), simulating the effects from both UV radiation and protons on the atmospheric chemistry of a hypothetical, Earth-like planet located within its habitable zone. Based on observations of solar proton events and the Neupert effect, we estimated a proton flux associated with the flare of 5.9 × 10⁸ protons cm⁻² sr⁻¹ s⁻¹ for particles with energies >10 MeV. Then we calculated the abundance of nitrogen oxides produced by the flare by scaling the production of these compounds during a large solar proton event called the Carrington event. The simulations were performed with a 1-D photochemical model coupled to a 1-D radiative/convective model. Our results indicate that the UV radiation emitted during the flare does not produce a significant change in the ozone column depth of the planet. When the action of protons is included, the ozone depletion reaches a maximum of 94% two years after the flare for a planet with no magnetic field. At the peak of the flare, the calculated UV fluxes that reach the surface, in the wavelength ranges that are damaging for life, exceed those received on Earth during less than 100 s. Therefore, flares may not present a direct hazard for life on the surface of an orbiting habitable planet. Given that AD Leo is one of the most magnetically active M dwarfs known, this conclusion should apply to planets around other M dwarfs with lower levels of chromospheric activity.

  7. Response of atmospheric biomarkers to NO(x)-induced photochemistry generated by stellar cosmic rays for earth-like planets in the habitable zone of M dwarf stars.

    Science.gov (United States)

    Grenfell, John Lee; Grießmeier, Jean-Mathias; von Paris, Philip; Patzer, A Beate C; Lammer, Helmut; Stracke, Barbara; Gebauer, Stefanie; Schreier, Franz; Rauer, Heike

    2012-12-01

    Understanding whether M dwarf stars may host habitable planets with Earth-like atmospheres and biospheres is a major goal in exoplanet research. If such planets exist, the question remains as to whether they could be identified via spectral signatures of biomarkers. Such planets may be exposed to extreme intensities of cosmic rays that could perturb their atmospheric photochemistry. Here, we consider stellar activity of M dwarfs ranging from quiet up to strong flaring conditions and investigate one particular effect upon biomarkers, namely, the ability of secondary electrons caused by stellar cosmic rays to break up atmospheric molecular nitrogen (N(2)), which leads to production of nitrogen oxides (NO(x)) in the planetary atmosphere, hence affecting biomarkers such as ozone (O(3)). We apply a stationary model, that is, without a time dependence; hence we are calculating the limiting case where the atmospheric chemistry response time of the biomarkers is assumed to be slow and remains constant compared with rapid forcing by the impinging stellar flares. This point should be further explored in future work with time-dependent models. We estimate the NO(x) production using an air shower approach and evaluate the implications using a climate-chemical model of the planetary atmosphere. O(3) formation proceeds via the reaction O+O(2)+M→O(3)+M. At high NO(x) abundances, the O atoms arise mainly from NO(2) photolysis, whereas on Earth this occurs via the photolysis of molecular oxygen (O(2)). For the flaring case, O(3) is mainly destroyed via direct titration, NO+O(3)→NO(2)+O(2), and not via the familiar catalytic cycle photochemistry, which occurs on Earth. For scenarios with low O(3), Rayleigh scattering by the main atmospheric gases (O(2), N(2), and CO(2)) became more important for shielding the planetary surface from UV radiation. A major result of this work is that the biomarker O(3) survived all the stellar-activity scenarios considered except for the strong

  8. Influence of Abrupt Change of Solar Mass on the Earth-like Planetary Orbit%太阳质量突变对类地行星轨道的影响

    Institute of Scientific and Technical Information of China (English)

    潘彩娟; 朱云锋; 马游

    2013-01-01

    Assuming that the terminated mass is confined within the range 0.4551~0.5813M⊙when sun is going to evolve into White Dwarf, the velocity sun ejecting the shell is much greater than the revolving velocity of earth-like planet, therefore we think that the solar mass change is instantaneous. Under the model of sun ejecting the shell, the radial velocity of earth-like planet has the same order of magnitude as its revolving velocity, the orbital eccentricity of earth-like planet varies with the range 1.7949~0.7240.%假设太阳演化为白矮星的终止质量范围是0.4551~0.5813 M⊙,太阳抛射壳层的速率远大于类地行星的公转速率,认为太阳的质量变化是瞬间的。在太阳抛射壳层的模型下,类地行星获得的径向速率的数值与其公转速率的数值在同一量级,类地行星的轨道偏心率的变化范围是1.7949~0.7240。

  9. Our World Their World

    Science.gov (United States)

    Brisco, Nicole

    2011-01-01

    Build, create, make, blog, develop, organize, structure, perform. These are just a few verbs that illustrate the visual world. These words create images that allow students to respond to their environment. Visual culture studies recognize the predominance of visual forms of media, communication, and information in the postmodern world. This…

  10. Our World Their World

    Science.gov (United States)

    Brisco, Nicole

    2011-01-01

    Build, create, make, blog, develop, organize, structure, perform. These are just a few verbs that illustrate the visual world. These words create images that allow students to respond to their environment. Visual culture studies recognize the predominance of visual forms of media, communication, and information in the postmodern world. This…

  11. World Literature - World Culture

    DEFF Research Database (Denmark)

    Offering their own twenty-first-century perspectives - across generations, nationalities and disciplines -, the contributors to this anthology explore the idea of world literature for what it may add of new connections and itineraries to the study of literature and culture today. Covering a vast ...... historical material these essays, by a diverse group of scholars, examine the pioneers of world literature and the roles played by translation, migration and literary institutions in the circulation and reception of both national and cosmopolitan literatures....

  12. World Literature - World Culture

    DEFF Research Database (Denmark)

    Offering their own twenty-first-century perspectives - across generations, nationalities and disciplines -, the contributors to this anthology explore the idea of world literature for what it may add of new connections and itineraries to the study of literature and culture today. Covering a vast...... historical material these essays, by a diverse group of scholars, examine the pioneers of world literature and the roles played by translation, migration and literary institutions in the circulation and reception of both national and cosmopolitan literatures....

  13. World law

    Directory of Open Access Journals (Sweden)

    Harold J. Berman

    1999-03-01

    Full Text Available In the third millennium of the Christian era, which is characterised by the emergence of a world economy and eventually a world society, the concept of world law is needed to embrace not only the traditional disciplines of public international law, and comparative law, but also the common underlying legal principles applicable in world trade, world finance, transnational transfer of technology and other fields of world economic law, as well as in such emerging fields as the protection of the world's environment and the protection of universal human rights. World law combines inter-state law with the common law of humanity and the customary law of various world communities.

  14. World law

    OpenAIRE

    Berman, Harold J.; Robert W. Woodruff; James Barr Ames

    1999-01-01

    In the third millennium of the Christian era, which is characterised by the emergence of a world economy and eventually a world society, the concept of world law is needed to embrace not only the traditional disciplines of public international law, and comparative law, but also the common underlying legal principles applicable in world trade, world finance, transnational transfer of technology and other fields of world economic law, as well as in such emerging fields as the protection of the ...

  15. Worlds Fantastic, Worlds Familiar

    Science.gov (United States)

    Buratti, Bonnie J.

    2017-02-01

    Introduction; 1. Mercury: the hottest little place; 2. Venus: an even hotter place; 3. Mars: the abode of life?; 4. Asteroids and comets: sweat the small stuff; 5. Galileo's treasures: worlds of fire and ice; 6. Enceladus: an active iceball in space; 7. Titan: an Earth in deep freeze?; 8. Iapetus and its friends: the weirdest 'planets' in the Solar System; 9. Pluto: the first view of the 'third zone'; 10. Earths above: the search for exoplanets and life in the universe; Epilogue; Glossary; Acknowledgements; Index.

  16. Titan the earth-like moon

    CERN Document Server

    Coustenis, Athena

    1999-01-01

    This is the first book to deal with Titan, one of the most mysterious bodies in the solar system. The largest satellite of the giant planet Saturn, Titan is itself larger than the planet Mercury, and is unique in being the only known moon with a thick atmosphere. In addition, its atmosphere bears a startling resemblance to the Earth's, but is much colder.The American and European space agencies, NASA and ESA, have recently combined efforts to send a huge robot spacecraft to orbit Saturn and land on Titan. This book provides the background to this, the greatest deep space venture of our time, a

  17. Chemical composition of Earth-like planets

    CERN Document Server

    Ronco, M P; Marboeuf, U; Alibert, Y; de Elía, G C; Guilera, O M

    2015-01-01

    Models of planet formation are mainly focused on the accretion and dynamical processes of the planets, neglecting their chemical composition. In this work, we calculate the condensation sequence of the different chemical elements for a low-mass protoplanetary disk around a solar-type star. We incorporate this sequence of chemical elements (refractory and volatile elements) in our semi-analytical model of planet formation which calculates the formation of a planetary system during its gaseous phase. The results of the semi-analytical model (final distributions of embryos and planetesimals) are used as initial conditions to develope N-body simulations that compute the post-oligarchic formation of terrestrial-type planets. The results of our simulations show that the chemical composition of the planets that remain in the habitable zone has similar characteristics to the chemical composition of the Earth. However, exist differences that can be associated to the dynamical environment in which they were formed.

  18. World Wind

    Data.gov (United States)

    National Aeronautics and Space Administration — World Wind allows any user to zoom from satellite altitude into any place on Earth, leveraging high resolution LandSat imagery and SRTM elevation data to experience...

  19. Virtual Worlds

    OpenAIRE

    Novák, František

    2009-01-01

    The bachelor's thesis is focused on highlighting the development of virtual worlds. The paper summarizes the evolution of virtual reality. Current virtual worlds are compared in fundamental aspects, such as sociology, economics and education. Social sphere describes the interaction in virtual reality and its specialities. Economical sphere is focused on comparison of real and virtual economies, including their economic indicators. Educational sphere describes the sciences, which are best usea...

  20. World Englishes

    Institute of Scientific and Technical Information of China (English)

    张严心; 周丽

    2014-01-01

    In the current days, the search for information and the need for global communication have already promoted English from being the language of people in different countries as the international language. This essay will give some arguments about the inevitability of variety of world Englishes and its characteristics, and then explain that what Standard English is and examples about the standards in English.

  1. Sophie's World

    OpenAIRE

    Nadja Dobnik

    1999-01-01

    ln this contribution, the author of­ fers a description of the book Zofia's World, by the Norwegian professor of philosophy, Jostein Gaarder, a work which is treated in literary theory mainly as an interesting post-modernist novel, since it would appear to be a presentation of the history of philosophy in the popular form of a novel. The author of this paper, however, sees far more in the book, which is indeed an exceptional philosophy textbook for independent study. It is, really, a correspo...

  2. Extraordinarily large perpendicular magnetic anisotropy in epitaxially strained cobalt-ferrite Co{sub x}Fe{sub 3−x}O{sub 4}(001) (x = 0.75, 1.0) thin films

    Energy Technology Data Exchange (ETDEWEB)

    Niizeki, Tomohiko; Utsumi, Yuji; Aoyama, Ryohei; Yanagihara, Hideto; Inoue, Jun-ichiro; Kita, Eiji [Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan); Yamasaki, Yuichi; Nakao, Hironori [Photon Factory and Condensed Matter Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Koike, Kazuyuki [Division of Physics, Graduate School of Science, Hokkaido University, Kita 10, Nishi 8, Kita-ku, Sapporo (Japan)

    2013-10-14

    Perpendicular magnetic anisotropy (PMA) of cobalt-ferrite Co{sub x}Fe{sub 3-x}O{sub 4} (x = 0.75 and 1.0) epitaxial thin films grown on MgO (001) by a reactive magnetron sputtering technique was investigated. The saturation magnetization was found to be 430 emu/cm{sup 3} for x = 0.75, which is comparable to that of bulk CoFe{sub 2}O{sub 4} (425 emu/cm{sup 3}). Torque measurements afforded PMA constants of K{sub u}{sup eff}=9.0 Merg/cm{sup 3} (K{sub u}=10.0 Merg/cm{sup 3}) and K{sub u}{sup eff}=9.7 Merg/cm{sup 3} for x = 0.75 and 1.0, respectively. The value of K{sub u}{sup eff} extrapolated using Miyajima's plot was as high as 14.7 Merg/cm{sup 3} for x = 1.0. The in-plane four-fold magnetic anisotropy was evaluated to be 1.6 Merg/cm{sup 3} for x = 0.75. X-ray diffraction measurement revealed our films to be pseudomorphically strained on MgO (001) with a Poisson ratio of 0.4, leading to a considerable in-plane tensile strain by which the extraordinarily large PMA could be accounted for.

  3. Mapping the Nearest Stars for Exotic Habitable Worlds

    Science.gov (United States)

    Seager, Sara

    2014-06-01

    Exoplanets are planets orbiting stars other than the sun. Thousands of exoplanets are known and thousands of more planet candidates have been found. Until now, the dominant focus on habitable worlds has been on Earth-like planets, because Earth is the only known planet with life. Yet exoplanets are astonishingly diverse—in terms of their masses, densities, orbits, and host star types—and this diversity motivates a radical extension of what conventionally constitutes a habitable planet. The race to find habitable exoplanets has accelerated with the realization that “big Earths” transiting small stars can be both discovered and characterized with current technology. Moreover, technology for space-based direct imaging of Earth analogs has been rapidly maturing. The ambitious goal of inferring signs of life via biosignature gases in an exoplanet atmosphere, once only a futuristic thought, is now within reach.

  4. Extraordinarily Egyptian Jewelry Fit for a Pharaoh.

    Science.gov (United States)

    Patterson, Berniece

    1999-01-01

    Presents an art lesson for sixth-grade students in which the students study the Egyptians' jewelry techniques and designs and create their own amulets. Provides background information on the importance of life after death to the Egyptians and how religion influenced the designing of their amulets. Describes the jewelry-making procedure. (CMK)

  5. The Search for Worlds Like Our Own

    Science.gov (United States)

    Fridlund, Malcolm; Eiroa, Carlos; Henning, Thomas; Herbst, Tom; Lammer, Helmut; Léger, Alain; Liseau, René; Paresce, Francesco; Penny, Alan; Quirrenbach, Andreas; Röttgering, Huub; Selsis, Franck; White, Glenn J.; Absil, Olivier; Defrère, D.; Schneider, Jean; Tinetti, Giovanna; Karlsson, Anders; Gondoin, Phillipe; den Hartog, Roland; D'Arcio, Luigi; Stankov, Anna-Maria; Kilter, Mikael; Erd, Christian; Beichman, Charles; Coulter, Daniel; Danchi, William; Devirian, Michael; Johnston, Kenneth J.; Lawson, Peter; Lay, Oliver P.; Lunine, Jonathan; Kaltenegger, Lisa

    2010-01-01

    The direct detection of Earth-like exoplanets orbiting nearby stars and the characterization of such planets -- particularly, their evolution, their atmospheres, and their ability to host life -- constitute a significant problem. The quest for other worlds as abodes of life has been one of mankind's great questions for several millennia. For instance, as stated by Epicurus 300 BC: Other worlds, with plants and other living things, some of them similar and some of them different from ours, must exist. Demokritos from Abdera (460-370 BC), the man who invented the concept of indivisible small parts - atoms - also held the belief that other worlds exist around the stars and that some of these worlds may be inhabited by life-forms. The idea of the plurality of worlds and of life on them has since been held by scientists like Johannes Kepler and William Herschel, among many others. Here, one must also mention Giordano Bruno. Born in 1548, Bruno studied in France and came into contact with the teachings of Nicolas Copernicus. He wrote the book De l'Infinito, Universo e Mondi in 1584, in which he claimed that the Universe was infinite, that it contained an infinite amount of worlds like Earth, and that these worlds were inhabited by intelligent beings. At the time, this was extremely controversial, and eventually Bruno was arrested by the church and burned at the stake in Rome in 1600, as a heretic, for promoting this and other equally confrontational issues (though it is unclear exactly which idea was the one that ultimately brought him to his end). In all the aforementioned cases, the opinions and results were arrived at through reasoning not by experiment. We have only recently acquired the technological capability to observe planets orbiting stars other than 6our Sun; acquisition of this capability has been a remarkable feat of our time. We show in this introduction to the Habitability Primer that mankind is at the dawning of an age when, by way of the scientific

  6. The search for worlds like our own.

    Science.gov (United States)

    Fridlund, Malcolm; Eiroa, Carlos; Henning, Thomas; Herbst, Tom; Lammer, Helmut; Léger, Alain; Liseau, René; Paresce, Francesco; Penny, Alan; Quirrenbach, Andreas; Röttgering, Huub; Selsis, Franck; White, Glenn J; Absil, Olivier; Defrère, Denis; Hanot, C; Stam, Daphne; Schneider, Jean; Tinetti, Giovanna; Karlsson, Anders; Gondoin, Phillipe; den Hartog, Roland; D'Arcio, Luigi; Stankov, Anna-Maria; Kilter, Mikael; Erd, Christian; Beichman, Charles; Coulter, Daniel; Danchi, William; Devirian, Michael; Johnston, Kenneth J; Lawson, Peter; Lay, Oliver P; Lunine, Jonathan; Kaltenegger, Lisa

    2010-01-01

    The direct detection of Earth-like exoplanets orbiting nearby stars and the characterization of such planets-particularly, their evolution, their atmospheres, and their ability to host life-constitute a significant problem. The quest for other worlds as abodes of life has been one of mankind's great questions for several millennia. For instance, as stated by Epicurus approximately 300 BC: "Other worlds, with plants and other living things, some of them similar and some of them different from ours, must exist." Demokritos from Abdera (460-370 BC), the man who invented the concept of indivisible small parts-atoms-also held the belief that other worlds exist around the stars and that some of these worlds may be inhabited by life-forms. The idea of the plurality of worlds and of life on them has since been held by scientists like Johannes Kepler and William Herschel, among many others. Here, one must also mention Giordano Bruno. Born in 1548, Bruno studied in France and came into contact with the teachings of Nicolas Copernicus. He wrote the book De l'Infinito, Universo e Mondi in 1584, in which he claimed that the Universe was infinite, that it contained an infinite amount of worlds like Earth, and that these worlds were inhabited by intelligent beings. At the time, this was extremely controversial, and eventually Bruno was arrested by the church and burned at the stake in Rome in 1600, as a heretic, for promoting this and other equally confrontational issues (though it is unclear exactly which idea was the one that ultimately brought him to his end). In all the aforementioned cases, the opinions and results were arrived at through reasoning-not by experiment. We have only recently acquired the technological capability to observe planets orbiting stars other than 6 our Sun; acquisition of this capability has been a remarkable feat of our time. We show in this introduction to the Habitability Primer that mankind is at the dawning of an age when, by way of the

  7. The Smallest Signatures of Other Worlds

    Science.gov (United States)

    Roy, Arpita

    2017-06-01

    As a litany of worlds gently tug on the stars around us, we are driven to build instruments that can discern the smallest stellar motions and reveal this population of planets. However, the path to extreme precision spectroscopy, required to detect Earth-like planets, is a difficult one that must be forged from technological and scientific discovery. Anchored by the success of HARPS and other precision spectrographs in the field, we are moving into the development of complete radial velocity systems that are capable of detecting small signatures in both the optical and near-infrared. I will discuss two such instruments being developed at Penn State: (a) the Habitable Zone Planet Finder, a NIR spectrograph for the 10m Hobby-Eberly Telescope, and (b) NEID, an extreme precision optical instrument which is the cornerstone of the NN-EXPLORE partnership. The science enabled by these instruments will be far-reaching, ranging from immediate follow-up of close-in TESS and K2 candidates, to identifying potentially well-separated targets for future space missions such as WFIRST-AFTA, HabEx or LUVOIR, and providing new insight into the hitherto unexplored connections between populaces of inner and outer solar systems.

  8. 早期心理危机干预在特大火灾救援中的应用%Early Psychological Crisis Intervention in Extraordinarily Serious Fire Accidents

    Institute of Scientific and Technical Information of China (English)

    陈健

    2011-01-01

    目的 探讨城市特大火灾后对灾民实施早期心理危机干预的方法和效果.方法 组织心理危机工作小组,深入灾民安置点,采用访谈法、观察法、测量法等手段,开展早期重点筛查、分类干预、预防自杀、跟踪随访等心理援助.结果 某心理干预工作小组2010年11月15-30日,共对安置点入住的173名灾民进行了2 413次心理干预筛查,心理危机干预治疗109人次,药物治疗54人次.共对14个急性应激障碍的重点关注对象进行心理援助,未发生自杀个案.结论 早期心理危机干预对处理灾后灾民心理问题起到积极作用,而政府主导地位、早期专家组督导、做好对心理干预工作者的支持援助是有效干预的保障.%Objective To investigate the effect of early psychological crisis intervention on the disaster victims of extraordinarily serious fire accidents in cities. Methods A well-organized working group was established for psychological crisis to visit the victims' settlements. Using Interviews, observation and measurement, a series of psychological assistance were implemented concerning early focus screening, classification intervention,suicide prevention, tracking and follow-up. Results From 15 to 30 in November 2010,A well-organized working group for psychological crisis conducted 2 413 cases psychological intervention screening on 173 victims,psychological intervention therapy on 109 cases and medical therapy on 54 cases. Psychological assistance was delivered to 14 focused objects with acute stress disorder without suicide case. Conclusion Early post-disaster psychological crisis intervention plays an active role in managing psychological problems,which was guarenteed with the dominant position of the government, early expert supervision and good support for aid workers in psychological intervention.

  9. The search for habitable worlds: 1. The viability of a starshade mission

    CERN Document Server

    Turnbull, Margaret C; Roberge, Aki; Cash, Webster; Noecker, Charley; Lo, Amy; Mason, Brian; Oakley, Phil; Bally, John

    2012-01-01

    As part of NASA's mission to explore habitable planets orbiting nearby stars, this paper explores the detection and characterization capabilities of a 4-m space telescope plus 50-m starshade located at the Earth-Sun L2 point, a.k.a. the New Worlds Observer (NWO). Our calculations include the true spectral types and distribution of stars on the sky, an iterative target selection protocol designed to maximize efficiency based on prior detections, and realistic mission constraints. We carry out both analytical calculations and simulated observing runs for a wide range in exozodiacal background levels ({\\epsilon} = 1 - 100 times the local zodi brightness) and overall prevalence of Earth-like terrestrial planets ({\\eta}\\oplus = 0.1 - 1). We find that even without any return visits, the NWO baseline architecture (IWA = 65 mas, limiting FPB = 4\\times10-11) can achieve a 95% probability of detecting and spectrally characterizing at least one habitable Earth-like planet, and an expectation value of ~3 planets found, w...

  10. Shanghai Highlight: World Expo

    Institute of Scientific and Technical Information of China (English)

    Guo Yan

    2009-01-01

    @@ The proposals regarding the Shanghai Expo attracted the World Expo committee great concern. During the two sessions, the Shanghai World Expo organizer promised that they will play more active role in holding the expo. Though the world is suffering the global crisis, the organizer be-lieved that this is a rare opportunity and as the World Expo 2010 to be held in Shanghai could help China overcome economic dif-ficulties and lift the world out of the crisis shadow.

  11. Teaching World Religions without Teaching "World Religions"

    Science.gov (United States)

    Locklin, Reid B.; Tiemeier, Tracy; Vento, Johann M.

    2012-01-01

    Tomoko Masuzawa and a number of other contemporary scholars have recently problematized the categories of "religion" and "world religions" and, in some cases, called for its abandonment altogether as a discipline of scholarly study. In this collaborative essay, we respond to this critique by highlighting three attempts to teach world religions…

  12. Scientists Plot Search For Earth--Like Planets

    Institute of Scientific and Technical Information of China (English)

    Andrew; Quinn; 金月芹

    1999-01-01

    1999年5月22日清晨,在Internet上读到此文,兴奋异常。遥望那无垠的、群星闪烁的夜空,人类很早就在思考:Are we alone in the universe?许多科幻小说中描写的外星人,更点燃了人类的想象。人们在无法解开金字塔的建造之谜时,仰望太空,猜测那是外星人在地球上留下的杰作;人们在惊叹UFO的神秘行踪时,也翘首天际,设想那是外星人在向我们暗递的“秋波”!今天,人类的科技终于驶入了一个新时代,能够更精确更清晰更自信地去探求茫茫宇宙里的奥秘。这篇报道的第一句就足以让我们欣喜: Somewhere,in a star system porhaps not so far away,lies a″ pale bluedot″which could be a planet much like Earth. 在这个淡蓝色的小点(pale blue dot)上也许就生活着人类的邻居。美国的一群科学家们上周就聚首在位于加州的NASA(国家航空和航天局)researchcenter,这次科学聚会就被称为The″Pale Blue Dot″Conference!再过10年,一个名为Terrestrial Planet Finder的宇宙望远镜将投入使用,届时,它将提供比目前的哈勃望远镜清晰100倍的图象。 美国亚利桑那州的的一位天文学家这样断言: Life on earth is by no means the only kind of life that can exist. 在即将过去的20世纪,人类登上了月球,失望地发现,那里除了环形山?

  13. Can Red Dwarf stars support Earth-like vegetation?

    Science.gov (United States)

    Gale, Joseph; Wandel, Amri

    2016-07-01

    The Kepler mission has shown that Earthlike planets are common. Of particular interest in our search for extra-solar-system, life-clement conditions, are planets orbiting Red Dwarf (RD) stars, the most numerous stellar type in the Milky Way galaxy. Early considerations indicated that conditions on RD planets would be inimical to life, as their Habitable Zones would be so close as to make planets tidally locked to their star. This was expected to engender tempestuous climates and to expose life forms to flares of ionizing electro-magnetic radiation and charged particles. Moreover, the less photon energy of the radiation of the relatively cool RDs would be too low in the 300-700nm waveband required for Oxygenic Photosynthesis (OP). Recent calculations show that these negative factors are less severe than originally estimated. Many authors have suggested that OP may evolve on RP planets to utilize infrared photons in the 700-1000nm waveband. However, projecting from OP and the vegetation in analogous regions on Earth, we argue that the evolutionary pressure to do so would be small. On RD planets there will be regions receiving continuous illumination, of moderate intensity, containing a significant component of photosynthetic 400-700nm radiation. On Earth, OP has been an essential factor in producing the Biosphere environment that enabled the appearance and evolution of complex life. We conclude that the conditions for OP could exist on RD planets and consequently the evolution of vegetation and complex life is possible (albeit not necessary). Furthermore, the huge number of RDs and their long lifetimes, make advanced vegetation, OP and consequently complex life on RD planets probable, and statistically more likely than on planets of solar type stars.

  14. A Direct Path to Finding Earth-Like Planets

    Science.gov (United States)

    Heap, Sara R.; Linder, Don J.

    2009-01-01

    As envisaged by the 2000 astrophysics decadal survey panel: The main goal of Terrestrial Planet Finder (TPF) is nothing less than to search for evidence of life on terrestrial planets around nearby stars . Here, we consider how an optical telescope paired with a free-flying occulter blocking light from the star can reach this goal directly, without knowledge of results from prior astrometric, doppler, or transit exoplanet observations. Using design reference missions and other simulations, we explore the potential of TPF-O to find planets in the habitable zone around their central stars, to spectrally characterize the atmospheres of detected planets, and to obtain rudimentary information about their orbits. We emphasize the importance of ozone absorption in the UV spectrum of a planet as a marker of photosynthesis by plants, algae, and cyanobacteria.

  15. Increasing the sensitivity of Kepler to Earth-like exoplanets

    Science.gov (United States)

    Foreman-Mackey, Daniel; Hogg, David W.; Schölkopf, Bernhard; Wang, Dun

    2015-01-01

    Many transiting exoplanets have been discovered using photometry from the Kepler mission but the results are still very incomplete in some of the most interesting parts of parameter space: small planetary radius and long orbital period. We have developed a method for detecting transiting exoplanet signals in stellar light curves that is more sensitive to small planets on long orbits than previously published procedures. It is standard practice to start by "de-trending" the light curves—by filtering—to remove the instrumental systematics and stellar variability from the time series. Instead, we build an flexible model for these effects using a Gaussian Process. We use as inputs to the Gaussian Process not just time but also the light curves of dozens of other stars. This exploits the causal structure of the problem: permitting the noise model to capture spacecraft-induced covariability. Since we know a priori that the other stars are causally unrelated to the star of interest, any information that they share must be due to systematics. A key motivation for our work is that any filtering—no matter how robust—reduces the amplitude of the signals of interest. By marginalizing over the stellar and instrumental variability while simultaneously fitting for the transits, we maintain sensitivity to transit signals and reduce contamination. We apply our method to light curves from the Kepler mission. Using synthetic transits generated by realistic planetary systems injected into raw aperture photometry from the pipeline, we determine the detection efficiency of our method and train a supervised classification algorithm to weed out false signals. Our pipeline returns all of the ingredients needed for studies of exoplanet populations: a catalog of planet candidates, posterior samples for the physical parameters of these planets and their host stars, and an empirical measurement of the detection efficiency as a function of all of these parameters.

  16. Spectropolarimetric signatures of Earth-like extrasolar planets

    NARCIS (Netherlands)

    Stam, D.M.

    2007-01-01

    We present results of numerical simulations of flux F and degree of polarization P of light that is reflected by Earth–like extrasolar planets orbiting solar type stars. Our results are presented as functions of the wavelength (from 0.3 to 1.0 μm, with 0.001 μm spectral resolution) and as functions

  17. Habitability and Multistability in Earth-like Planets

    CERN Document Server

    Lucarini, Valerio; Boschi, Robert; Kirk, Edilbert; Iro, Nicolas

    2013-01-01

    We explore the potential multistability of the climate for a planet around the habitable zone. We focus on conditions reminiscent to those of the Earth system, but our investigation aims at presenting a general methodology for dealing with exoplanets. We provide a thorough analysis of the non-equilibrium thermodynamical properties of the climate system and explore, using a a flexible climate model, how such properties depend on the energy input of the parent star, on the infrared atmospheric opacity, and on the rotation rate. It is possible to reproduce the multi-stability properties reminiscent of the paleoclimatologically relevant snowball (SB) - warm (W) conditions. We then study the thermodynamics of the W and SB states, clarifying the role of the hydrological cycle in shaping the irreversibility and the efficiency of the W states, and emphasizing the extreme diversity of the SB states, where dry conditions are realized. Thermodynamics provides the clue for studying the tipping points of the system and le...

  18. Beyond Kepler: Direct Imaging of Earth-like Planets

    Science.gov (United States)

    Belikov, Ruslan

    2012-01-01

    Is there another Earth out there? Is there life on it? People have been asking these questions for over two thousand years, and we finally stand on the verge of answering them. The Kepler space telescope is NASA's first mission designed to study Earthlike exoplanets (exo-Earths), and it will soon tell us how often exo-Earths occur in the habitable zones of their stars. The next natural step after Kepler is spectroscopic characterization of exo-Earths, which would tell us whether they possess an atmosphere, oxygen, liquid water, as well as other biomarkers. In order to do this, directly imaging an exo-Earth may be necessary (at least for Sun-like stars). Directly imaging an exo-Earth is challenging and likely requires a flagship-size optical space telescope with an unprecedented imaging system capable of achieving contrasts of 1(exp 10) very close to the diffraction limit. Several coronagraphs and external occulters have been proposed to meet this challenge and are in development. After first overviewing the history and current state of the field, my talk will focus on the work proceeding at the Ames Coronagraph Experiment (ACE) at the NASA Ames Research Center, where we are developing the Phase Induced Amplitude Apodization (PIAA) coronagraph in a collaboration with JPL. PIAA is a powerful technique with demonstrated aggressive performance that defines the state of the art at small inner working angles. At ACE, we have achieved contrasts of 2(exp -8) with an inner working angle of 2 lambda/D and 1(exp -6) at 1.4 lambda/D. On the path to exo-Earth imaging, we are also pursuing a smaller telescope concept called EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer), which was recently selected for technology development (Category III) by NASA's Explorer program. EXCEDE will do fundamental science on debris disks as well as serve as a technological and scientific pathfinder for an exo-Earth imaging mission.

  19. A Direct Path to Finding Earth-Like Planets

    Science.gov (United States)

    Heap, Sara R.; Linder, Don J.

    2009-01-01

    As envisaged by the 2000 astrophysics decadal survey panel: The main goal of Terrestrial Planet Finder (TPF) is nothing less than to search for evidence of life on terrestrial planets around nearby stars . Here, we consider how an optical telescope paired with a free-flying occulter blocking light from the star can reach this goal directly, without knowledge of results from prior astrometric, doppler, or transit exoplanet observations. Using design reference missions and other simulations, we explore the potential of TPF-O to find planets in the habitable zone around their central stars, to spectrally characterize the atmospheres of detected planets, and to obtain rudimentary information about their orbits. We emphasize the importance of ozone absorption in the UV spectrum of a planet as a marker of photosynthesis by plants, algae, and cyanobacteria.

  20. Recognized by the World

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    China Danxia gets added to world heritage list as a natural site On August 1,2010,UNESCO’s World Heritage Committee inscribed China Danxia as a natural site in the world heritage list at its 34th session held from July 25 to August 3 this year in Brasilia,capital of Brazil.

  1. New World View

    Science.gov (United States)

    Bainbridge, William Sims

    This chapter reports the wide range of ideas in a pair of major scientific conference meetings held inside the most popular virtual world, World of Warcraft (WoW), May 9 and May 10, 2008, plus the challenges of organizing these online events. More than a hundred scholars and scientists contributed to each session, the first covering research on World of Warcraft, and the second examining how virtual worlds fit into the larger world of human experience. A third session, held on May 11, was the starting point for the concluding chapter of this volume. This chapter describes how WoW and other virtual worlds can be used as laboratories for studying human behavior, using both qualitative and quantitative methodologies, and the affordances of virtual worlds can be used to support scientific communication (Bainbridge 2007, in press).

  2. Teaching World Religions without Teaching "World Religions"

    Science.gov (United States)

    Locklin, Reid B.; Tiemeier, Tracy; Vento, Johann M.

    2012-01-01

    Tomoko Masuzawa and a number of other contemporary scholars have recently problematized the categories of "religion" and "world religions" and, in some cases, called for its abandonment altogether as a discipline of scholarly study. In this collaborative essay, we respond to this critique by highlighting three attempts to teach…

  3. Teaching World Religions without Teaching "World Religions"

    Science.gov (United States)

    Locklin, Reid B.; Tiemeier, Tracy; Vento, Johann M.

    2012-01-01

    Tomoko Masuzawa and a number of other contemporary scholars have recently problematized the categories of "religion" and "world religions" and, in some cases, called for its abandonment altogether as a discipline of scholarly study. In this collaborative essay, we respond to this critique by highlighting three attempts to teach…

  4. My World Indoors: My Health My World.

    Science.gov (United States)

    Tharp, Barbara; Dresden, Judith; Denk, James; Moreno, Nancy

    This curriculum guide for students in grades K-4 is part of the My Health My World series which explores environmental health issues. Focusing on indoor environmental health, it includes (1) an activities guide for teachers which focuses on physical science, life science, and the environment and health, presenting activity based lessons that…

  5. World Health Statistics 2005

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ The World Health Organization (WHO) collects and summarizes a wide range of quantitative data from a variety of health domains through country offices, regional offices and headquarter departments.

  6. Fermentation. Third World Science.

    Science.gov (United States)

    Jones, Natalie; Hughes, Wyn

    This unit, developed by the Third World Science Project, is designed to add a multicultural element to existing science syllabi (for students aged 11-16) in the United Kingdom. The project seeks to develop an appreciation of the: boundless fascination of the natural world; knowledge, skills, and expertise possessed by men/women everywhere;…

  7. Fermentation. Third World Science.

    Science.gov (United States)

    Jones, Natalie; Hughes, Wyn

    This unit, developed by the Third World Science Project, is designed to add a multicultural element to existing science syllabi (for students aged 11-16) in the United Kingdom. The project seeks to develop an appreciation of the: boundless fascination of the natural world; knowledge, skills, and expertise possessed by men/women everywhere;…

  8. Educating for World Cooperation.

    Science.gov (United States)

    Berman, Louise M.; Miel, Alice

    This booklet presents a variety of perspectives on educating for world cooperation. Section 1 discusses major world problems and calls for the reorientation of education as a potential solution. Section 2 deals with the design of such a reorientation and offers three approaches to teaching and curriculum development--knowing, being, and doing. In…

  9. On Observing World English.

    Science.gov (United States)

    Urdang, Lawrence

    1990-01-01

    Reviews the current state of World English. Subjects addressed include standard accents and dialects, prejudicial attitudes toward nonstandard "local" usages, the use of English as the language of diplomacy, American influences on the language, and the fracturing of English in non-English-speaking countries around the world. (17 references) (JL)

  10. Education and World Order

    Science.gov (United States)

    Jones, Phillip W.

    2007-01-01

    The impact on educational analysis of mainstream international relations (IR) theories is yet to realize its full potential. The problem of education in relation to the construction of world order is considered in relation to core developments in IR theory since the Second World War. In particular, the global architecture of education is seen as a…

  11. World Music Resources

    Science.gov (United States)

    Beegle, Amy C.

    2012-01-01

    Access to world music resources such as videos and sound recordings have increased with the advent of YouTube and the efforts of music educators working closely with ethnomusicologists to provide more detailed visual and audio information about various musical practices. This column discusses some world music resources available for music…

  12. Virtual World Security Inspection

    Directory of Open Access Journals (Sweden)

    Nicholas Charles Patterson

    2012-06-01

    Full Text Available Virtual property theft is a serious problem that exists in virtual worlds. Legitimate users of these worlds invest considerable amounts of time, effort and real-world money into obtaining virtual property, but unfortunately, are becoming victims of theft in high numbers. It is reported that there are over 1 billion registered users of virtual worlds containing virtual property items worth an estimated US$50 billion dollars. The problem of virtual property theft is complex, involving many legal, social and technological issues. The software used to access virtual worlds is of great importance as they form the primary interface to these worlds and as such the primary interface to conduct virtual property theft. The security vulnerabilities of virtual world applications have not, to date, been examined. This study aims to use the process of software inspection to discover security vulnerabilities that may exist within virtual world software – vulnerabilities that enable virtual property theft to occur. Analyzing three well know virtual world applications World of Warcraft, Guild Wars and Entropia Universe, this research utilized security analysis tools and scenario testing with focus on authentication, trading, intruder detection and virtual property recovery. It was discovered that all three examples were susceptible to keylogging, mail and direct trade methods were the most likely method for transferring stolen items, intrusion detection is of critical concern to all VWEs tested, stolen items were unable to be recovered in all cases and lastly occurrences of theft were undetectable in all cases. The results gained in this study present the key problem areas which need to be addressed to improve security and reduce the occurrence of virtual property theft.

  13. World energy resources

    Science.gov (United States)

    Clerici, A.; Alimonti, G.

    2015-08-01

    As energy is the main "fuel" for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC) has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER) 2013, is presented together with the evolution of the world energy resources over the last twenty years.

  14. World energy resources

    Directory of Open Access Journals (Sweden)

    Clerici A.

    2015-01-01

    Full Text Available As energy is the main “fuel” for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER 2013, is presented together with the evolution of the world energy resources over the last twenty years.

  15. World gravity standards

    Science.gov (United States)

    Uotila, U. A.

    1978-01-01

    In order to use gravity anomalies in geodetic computations and geophysical interpretations, the observed gravity values from which anomalies are derived should be referred to one consistent world wide system. The International Gravity Standardization Net 1971 was adapted by the International Union of Geodesy and Geophysics at Moscow in 1971, the network was result of extensive cooperation by many organizations and individuals around the world. The network contains more than 1800 stations around the world. The data used in the adjustment included more than 25,000 gravimetry, pendulum and absolute measurements.

  16. Constructing public worlds

    DEFF Research Database (Denmark)

    Jovchelovitch, Sandra; Priego-Hernandez, Jacqueline; Glaveanu, Vlad Petre

    2013-01-01

    and their social world. Drawings by children from two age groups (seven- and 10-year-olds) and two socio-economic milieus (affluent and deprived), in four cultures (Germany, Mexico, Brazil and Romania), supported by observations and interviews, were used to investigate children’s representations of their public...... world and their position within it. Findings show that public spheres characterised by collectivism, poverty and/or marginalisation: a) accelerate decentration bringing the public world and its complexity to the foreground of children’s depictions, and b) show a strong link between self and the public...

  17. Curing The World

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The WHO approves China’s vaccine regulation system The World Health Organization (WHO) said China had complied with international standards for the regulation of vaccines after it completed the assessment procedures at the end of 2010.

  18. World Magnetic Model 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The World Magnetic Model is the standard model used by the U.S. Department of Defense, the U.K. Ministry of Defence, the North Atlantic Treaty Organization (NATO)...

  19. Brazil World Cup Challenges

    Directory of Open Access Journals (Sweden)

    MANSUR, R.

    2012-12-01

    Full Text Available Overcoming the productivity challenge is the main benefit of the 2014 World Cup for Brazilian people. The sustainable development of our cultural tourism industry will catapult the new middle class growing up rate.

  20. The world's biggest experiment

    CERN Document Server

    Gregson, Liz

    2008-01-01

    According to CERN, our understanding of the Universe is about the change. Meet the Imperial alumni and staff who are involved in CERN's Large Hadron Collider, the world's biggest experiment. (3 pages)

  1. World Trade Center

    Index Scriptorium Estoniae

    2006-01-01

    Esilinastus katastroofifilm "World Trade Center" : stsenarist Andrea Berloff : režissöör Oliver Stone : kunstnik Jan Roelfs : osades Nicholas Cage, Michael Pena, Stephen Dorff jpt : Ameerika Ühendriigid 2006. Ka filmi prototüüpidest

  2. World Glacier Inventory

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The World Glacier Inventory (WGI) contains information for over 130,000 glaciers. Inventory parameters include geographic location, area, length, orientation,...

  3. World Government: Utopia?

    Directory of Open Access Journals (Sweden)

    Vahram Ayvazyan

    2012-07-01

    Full Text Available The aim of this paper is to analyze the possibility of having a world government, which world has been facing overarching changes since the end of Cold war, where bipolar world order has evolved into multipolar system through unipolarity. Analysis method in this paper have the sistematics: discussion of human nature and philosophical dimensions vis-à-vis individual, society and government, as well as society of societies; then briefly analyse globalization, the impact of individuals on interdependency of the current international arena and examine the individualism as the ongoing ideology “by individuals and for individuals.”; and then take the conclusion that the world government is not a utopia

  4. World Trade Center

    Index Scriptorium Estoniae

    2006-01-01

    Esilinastus katastroofifilm "World Trade Center" : stsenarist Andrea Berloff : režissöör Oliver Stone : kunstnik Jan Roelfs : osades Nicholas Cage, Michael Pena, Stephen Dorff jpt : Ameerika Ühendriigid 2006. Ka filmi prototüüpidest

  5. Monitoring the world's agriculture

    NARCIS (Netherlands)

    Sachs, J.; Remans, R.; Smukler, S.; Winowiecki, L.; Andelman, S.J.; Cassman, K.G.; Castle, D.; DeFries, R.; Denning, G.; Fanzo, J.; Jackson, L.E.; Leemans, R.; Lehman, J.; Milder, J.S.; Naeem, S.; Nziguheba, G.; Palm, C.A.; Pingali, P.L.; Reganold, J.P.; Richter, D.D.; Scherr, S.J.; Sircely, J.; Sullivan, C.; Tomich, T.P.; Sanchez, P.A.

    2010-01-01

    To feed the world without further damaging the planet, Jeffrey Sachs and 24 food-system experts call for a global data collection and dissemination network to track the myriad impacts of different farming practices.

  6. Monitoring the world's agriculture.

    Science.gov (United States)

    Sachs, Jeffrey; Remans, Roseline; Smukler, Sean; Winowiecki, Leigh; Andelman, Sandy J; Cassman, Kenneth G; Castle, David; DeFries, Ruth; Denning, Glenn; Fanzo, Jessica; Jackson, Louise E; Leemans, Rik; Lehmann, Johannes; Milder, Jeffrey C; Naeem, Shahid; Nziguheba, Generose; Palm, Cheryl A; Pingali, Prabhu L; Reganold, John P; Richter, Daniel D; Scherr, Sara J; Sircely, Jason; Sullivan, Clare; Tomich, Thomas P; Sanchez, Pedro A

    2010-07-29

    To feed the world without further damaging the planet, Jeffrey Sachs and 24 foodsystem experts call for a global data collection and dissemination network to track the myriad impacts of different farming practices.

  7. Brazil World Cup Challenges

    OpenAIRE

    MANSUR, R.

    2012-01-01

    Overcoming the productivity challenge is the main benefit of the 2014 World Cup for Brazilian people. The sustainable development of our cultural tourism industry will catapult the new middle class growing up rate.

  8. IS THE WORLD FLAT?

    Directory of Open Access Journals (Sweden)

    Cristian Încalţărău

    2010-06-01

    Full Text Available Globalization became more and more prominent during the last decades. There is no way to argue that globalization led to more interconnected economies, facilitating the communication and the collaboration around the world. But where is this going? Doesglobalization mean uniformity or diversity? As the world begins to resemble more, the people are trying to distinguish between them more, which can exacerbate nationalistic feeling. Friedman argues that globalization made the world smaller and flatter, allowing all countries to take chance of the available opportunities equally. But is this really true? Although politic and cultural factors can stand in front of a really flat world, what is the key for Chinese and Indian success and which are theirs perspectives?

  9. World Magnetic Model 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The World Magnetic Model is the standard model used by the U.S. Department of Defense, the U.K. Ministry of Defence, the North Atlantic Treaty Organization (NATO)...

  10. Fitness World - Fremtidig overlevelse

    OpenAIRE

    Rice, Kasper; Klink, Nikolaj; Nielsen, Mie; Carlson, Andre; Boy, Mikkel; Hansen, Alexander

    2015-01-01

    Our project is a case study with Fitness World as a baseline. Our project will enhance Fitness Worlds penetration on their current position on the market. Our empiricism includes both qualitative and quantitative methodical approaches by the use of an expert interview and a questionnaire survey. These methods contribute and generate general knowledge about the fitness culture in Denmark and the customers in the fitness industry. We have stated a possible strategic opportunity for Fitness Worl...

  11. Hosting the World

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Hangzhou and surrounding communities open their doors to leisure and tourism The 2006 World Leisure Expo opens its doors in the scenic city of Hangzhou, in east China’s Zhejiang Province, from April 22 to October 22. The Expo, which was co-sponsored by the World Leisure Organization (WLO), National Tourism Administration and the Zhejiang Provincial Government, highlights the many recreational facets of Hangzhou.

  12. World competitiveness and agriculture

    Directory of Open Access Journals (Sweden)

    J. van Zyl

    1997-07-01

    Full Text Available Against the background of a changing environment in which market factors and greater world trade and competitiveness are increasingly becoming the only criteria for success, a framework for the analysis of world competitiveness is initially developed. This is followed by a discussion on the growth of productivity in agriculture, as well as an exposition of the role of agricultural research. Thirdly, price factors and the terms of trade are discussed, followed by a summary of policy implications.

  13. Inside-My-World

    OpenAIRE

    Clemens Fessler; Claudia Tassotti

    2012-01-01

    Inside-My-World ist die erste Offline-Plattform, auf der man Freundinnen und Freunde kennenlernen, sich im Chat oder in Foren unterhalten, spannende Games spielen oder ganz einfach das eigene Profil gestalten und auf die Pinnwand seiner Freundinnen und Freunde schreiben kann.Diese Plattform hat den Vorteil, dass zum Einstieg keine Computer und keine Internetverbindung notwendig sind, da sie in jedem Raum, z.B. in einem Klassenzimmer, entstehen kann. Denn Inside-My-World ist ein Soziales Netzw...

  14. Brane World Cosmological Perturbations

    CERN Document Server

    Casali, A G; Wang, B; Casali, Adenauer G.; Abdalla, Elcio; Wang, Bin

    2004-01-01

    We consider a brane world and its gravitational linear perturbations. We present a general solution of the perturbations in the bulk and find the complete perturbed junction conditions for generic brane dynamics. We also prove that (spin 2) gravitational waves in the great majority of cases can only arise in connection with a non-vanishing anisotropic stress. This has far reaching consequences for inflation in the brane world. Moreover, contrary to the case of the radion, perturbations are stable.

  15. Can old-world and new-world monkeys judge spatial above/below relations to be the same or different? Some of them, but not all of them.

    Science.gov (United States)

    Thompson, Roger K R; Flemming, Timothy M; Hagmann, Carl Erick

    2016-02-01

    Chimpanzees (Pan troglodytes) with the aid of token training can achieve analogical reasoning, or the ability to understand relations-between-relations (e.g., Premack, 1976; Thompson, Oden, & Boysen, 1997). However, extraordinarily few numbers of old- and new-world monkeys have demonstrated this ability in variants of relational matching to sample tasks. Moreover, the rarity of replications leaves open the question of whether the results are normative for other captive colonies of the same species. In experiment one we attempted to replicate whether old world rhesus monkeys (Macaca mulatta) might demonstrate the same level of proficiency on a spatial above/below relational matching task as reported for old world baboons (Papio papio). None of the rhesus monkeys attained above chance performances over 10,000 training trials. In experiment two we attempted to replicate results demonstrating that new-world capuchin monkeys (Cebus apella) match above/below relations. The capuchin monkeys performed above chance only in the absence of 'Clever Hans' controls for cuing of the correct choice by the experimenters. These failures to replicate previously reported results demonstrate that some, but definitely not all monkeys can judge the equivalence of abstract 'relations between relations' and warrant further investigations into the behavioral and cognitive characteristics that underlie these similarities and differences within population and between individuals of different primate species.

  16. Detecting Exoplanets with the New Worlds Observer: The Problem of Exozodiacal Dust

    Science.gov (United States)

    Roberge, A.; Noecker, M. C.; Glassman, T. M.; Oakley, P.; Turnbull, M. C.

    2009-01-01

    Dust coming from asteroids and comets will strongly affect direct imaging and characterization of terrestrial planets in the Habitable Zones of nearby stars. Such dust in the Solar System is called the zodiacal dust (or 'zodi' for short). Higher levels of similar dust are seen around many nearby stars, confined in disks called debris disks. Future high-contrast images of an Earth-like exoplanet will very likely be background-limited by light scattered of both the local Solar System zodi and the circumstellar dust in the extrasolar system (the exozodiacal dust). Clumps in the exozodiacal dust, which are expected in planet-hosting systems, may also be a source of confusion. Here we discuss the problems associated with imaging an Earth-like planet in the presence of unknown levels of exozodiacal dust. Basic formulae for the exoplanet imaging exposure time as function of star, exoplanet, zodi, exozodi, and telescope parameters will be presented. To examine the behavior of these formulae, we apply them to the New Worlds Observer (NWO) mission. NWO is a proposed 4-meter UV/optical/near-IR telescope, with a free flying starshade to suppress the light from a nearby star and achieve the high contrast needed for detection and characterization of a terrestrial planet in the star's Habitable Zone. We find that NWO can accomplish its science goals even if exozodiacal dust levels are typically much higher than the Solar System zodi level. Finally, we highlight a few additional problems relating to exozodiacal dust that have yet to be solved.

  17. The Search for Habitable Worlds. 1. The Viability of a Starshade Mission

    Science.gov (United States)

    Turnbull, Margaret C.; Glassman, Tiffany; Roberge, Aki; Cash, Webster; Noecker, Charley; Lo, Amy; Mason, Brian; Oakley, Phil; Bally, John

    2012-01-01

    As part of NASA's mission to explore habitable planets orbiting nearby stars, this article explores the detection and characterization capabilities of a 4 m space telescope plus 50 m starshade located at the Earth-Sun L2 point, known as the New Worlds Observer (NWO). Our calculations include the true spectral types and distribution of stars on the sky, an iterative target selection protocol designed to maximize efficiency based on prior detections, and realistic mission constraints. We conduct simulated observing runs for a wide range in exozodiacal background levels (epsilon = 1-100 times the local zodi brightness) and overall prevalence of Earth-like terrestrial planets (eta(sub solar halo))0.1-1). We find that even without any return visits, the NWO baseline architecture (IWA = 65 mas, limiting FPB = 4 x 10(exp -11) can achieve a 95% probability of detecting and spectrally characterizing at least one habitable Earth-like planet and an expectation value of approximately 3 planets found, within the mission lifetime and delta V budgets, even in the worst-case scenario (eta(sub solar halo) = 0.1 and = epsilon = 100 zodis for every target). This achievement requires about 1 yr of integration time spread over the 5 yr mission, leaving the remainder of the telescope time for UV-NIR general astrophysics. Cost and technical feasibility considerations point to a "sweet spot" in starshade design near a 50 m starshade effective diameter. with 12 or 16 petals, at a distance of 70,000-100,000 km from the telescope.

  18. Systems astrobiology for a reliable biomarker on exo-worlds

    Science.gov (United States)

    Chela Flores, Julian

    2013-04-01

    Although astrobiology is a science midway between biology and astrophysics, it has surprisingly remained largely disconnected from recent trends in certain branches of both of these disciplines. Aiming at discovering how systems properties emerge has proved valuable in chemistry and in biology and should also yield insights into astrobiology. This is feasible since new large data banks in the case of astrobiology are of a geophysical/astronomical kind, rather than the also large molecular biology data that are used for questions related firstly, to genetics in a systems context and secondly, to biochemistry. The application of systems biology is illustrated for our own planetary system, where 3 Earth-like planets are within the habitable zone of a G2V star and where the process of photosynthesis has led to a single oxygenic atmosphere that was triggered during the Great Oxidation Event some 2,5 billion years before the present. The significance of the biogenic origin of a considerable fraction of our atmosphere has been discussed earlier (Kiang et al., 2007). Bonding of O2 ensures that it is stable enough to accumulate in a world's atmosphere if triggered by a living process. The reduction of F and Cl deliver energy release per e+-transfer, but unlike O2 the weaker bonding properties inhibit large atmospheric accumulation (Catling et al., 2005). The evolution of O2-producing photosynthesis is very likely on exo-worlds (Wolstencroft and Raven, 2002). With our simplifying assumption of evolutionary convergence, we show how to probe for a reliable biomarker in the exo-atmospheres of planets, or their satellites, orbiting stars of different luminosities and ages (Chela-Flores, 2013). We treat the living process as a system of exo-environments capable of radically modifying their geology and atmospheres, both for exo-planets, and especially for exo-moons, the presence of which can be extracted from the Kepler data (Kipping et al., 2012). What we are learning about the

  19. When Virtual Worlds Expand

    Science.gov (United States)

    Bainbridge, William Sims

    The future of a virtual world depends on whether it can grow in subjective size, cultural content, and numbers of human participants. In one form of growth, exemplified by Second Life, the scope of a world increases gradually as new sponsors pay for new territory and inhabitants create content. A very different form of growth is sudden expansion, as when World of Warcraft (WoW) added entire new continents in its Burning Crusade and Lich King expansions (Lummis and Kern 2006, 2008; Corneliussen and Rettberg 2008; Sims et al. 2008). Well-established gamelike worlds have often undergone many expansions. Both the pioneer science fiction game Anarchy Online, which was launched in 2001, and Star Wars Galaxies dating from 2003, have had three, and EVE Online also from 2003 has had nine, although smaller ones. This chapter reports research on WoW's 2008 Lich King expansion, using both quantitative and qualitative methods, in order to develop theoretical ideas of the implications of expansion for virtual worlds.

  20. The Africana world

    DEFF Research Database (Denmark)

    diaspora in order for the unity and renaissance dreamed of to become a reality. The chapters in Africana World: From Fragmentation to Unity and Renaissance address colonial and postcolonial African realities with a view to present a holistic and transcontinental appraisal of questions, issues...... and challenges that confront the continent. Contributors are drawn from different parts of the world - Africa, Europe and the Americas - and it is this eclectic range of scholarly views that lends a rich historicity to the meaning of Africanity. The book contains multidisciplinary and transdisciplinary...... engagements with Africa's rich cultural heritage, its lingering contemporary challenges, its multifaceted systems of knowledge and its future in the exciting context of the twenty-first century. Africana World: From Fragmentation to Unity and Renaissance is put together in order to help develop the study...

  1. Surfing the quantum world

    CERN Document Server

    Levin, Frank S

    2017-01-01

    The ideas and phenomena of the quantum world are strikingly unlike those encountered in our visual world. Surfing the Quantum World shows why and how this is so. It does this via a historical review and a gentle introduction to the fundamental principles of quantum theory, whose core concepts and symbolic representations are used to explain not only "ordinary" microscopic phenomena like the properties of the hydrogen atom and the structure of the Periodic Table of the Elements, but also a variety of mind-bending phenomena. Readers will learn that particles such as electrons and photons can behave like waves, allowing them to be in two places simultaneously, why white dwarf and neutron stars are gigantic quantum objects, how the maximum height of mountains has a quantum basis, and why quantum objects can tunnel through seemingly impenetrable barriers. Included among the various interpretational issues addressed is whether Schrodinger's cat is ever both dead and alive.

  2. The Africana world

    DEFF Research Database (Denmark)

    diaspora in order for the unity and renaissance dreamed of to become a reality. The chapters in Africana World: From Fragmentation to Unity and Renaissance address colonial and postcolonial African realities with a view to present a holistic and transcontinental appraisal of questions, issues...... engagements with Africa's rich cultural heritage, its lingering contemporary challenges, its multifaceted systems of knowledge and its future in the exciting context of the twenty-first century. Africana World: From Fragmentation to Unity and Renaissance is put together in order to help develop the study...... and challenges that confront the continent. Contributors are drawn from different parts of the world - Africa, Europe and the Americas - and it is this eclectic range of scholarly views that lends a rich historicity to the meaning of Africanity. The book contains multidisciplinary and transdisciplinary...

  3. World energy insight 2011

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    The World Energy Insight 2011 is the official publication of the World Energy Council. It includes interviews, articles and case studies from a distinguished panel of World Energy Council Officers, CEOs, government ministers, academics and opinion formers from all areas of the energy sector and provides perspectives from around the globe. Government, industry and NGO's offer both policy and technology perspectives. The insights within this publication add to the work that WEC is doing to provide the forum for energy leaders, along with the on-going WEC studies and programmes on Energy Policies, 2050 Energy Scenarios, Energy Resources & Technologies, Energy for Urban Innovation, Rules Of Energy Trade and Global Energy Access.

  4. The "Ghostly" Quantum Worlds

    CERN Document Server

    Dugic, M

    2011-01-01

    The quantum Universe can be decomposed into subsystems in different ways. We consider the global linear-canonical-transformations-based decompositions (structures) of the Universe. These structures bear the same physical time and the common the fundamental physical law--the Schrodinger law. The Universe quantum state is unique in every instant of time yet bearing the different forms for the different structures of the Universe. This simple corollary of the universally valid quantum mechanics points out that the intelligent agents in a structure may (globally) affect the other structures--the other "worlds". Locally considered non-spontaneous, such effects may seem "ghostly" within the alternative worlds. This picture of the one and the unique quantum Universe is competitive with both the Everett MWI as well as with the Bohmian pilot-wave interpretation, not yet being inconsistent with the "state collapse" interpretation of quantum mechanics. The "ghostly worlds" interpretation here we introduce may prove irre...

  5. Designing Virtual Worlds

    DEFF Research Database (Denmark)

    Gürsimsek, Remzi Ates

    2014-01-01

    The online social platforms known as virtual worlds present their users various affordances for avatar based co-presence, social interaction and provide tools for collaborative content creation, including objects, textures and animations. The users of these worlds navigate their avatars as personal...... mediators in 3D virtual space to collaborate and co-design the digital content. These co-designers are also the residents of these worlds, as they socialize by building inworld friendships. This article presents a social semiotic analysis of the three-dimensional virtual places and artifacts in the virtual...... the audio-visual characteristics of designing in multi-user virtual environments generate experiential, interpersonal and textual meaning potentials....

  6. The world's biggest gamble

    Science.gov (United States)

    Rockström, Johan; Schellnhuber, Hans Joachim; Hoskins, Brian; Ramanathan, Veerabhadran; Schlosser, Peter; Brasseur, Guy Pierre; Gaffney, Owen; Nobre, Carlos; Meinshausen, Malte; Rogelj, Joeri; Lucht, Wolfgang

    2016-10-01

    The scale of the decarbonisation challenge to meet the Paris Agreement is underplayed in the public arena. It will require precipitous emissions reductions within 40 years and a new carbon sink on the scale of the ocean sink. Even then, the world is extremely likely to overshoot. A catastrophic failure of policy, for example, waiting another decade for transformative policy and full commitments to fossil-free economies, will have irreversible and deleterious repercussions for humanity's remaining time on Earth. Only a global zero carbon roadmap will put the world on a course to phase-out greenhouse gas emissions and create the essential carbon sinks for Earth-system stability, without which, world prosperity is not possible.

  7. The Emerging World Order

    Directory of Open Access Journals (Sweden)

    PETER COLLECOTT

    2014-05-01

    Full Text Available It is common ground amongst almost all commentators that the world has changed radically over the past 25 years – the 25 years since the fall of the Berlin Wall heralded the ending of the Cold War, the reunification of a tragically divided Europe, and the acceleration of the process of globalisation which has its only comparable period in the decades leading up to the First World War in 1914. When analyzing the Emerging World Order it is important to cover more than Brazil economy or any other individual BRICs or other Emerging Powers. Instead, our analysis will provide a global view about the economic and political global power structures which are evolving and forming before our eyes, and then to talk about the challenges these emerging realities pose for us in Europe, and in the West in general.

  8. World Energy Future

    Energy Technology Data Exchange (ETDEWEB)

    Forbes, A.; Van der Linde, C.; Nicola, S.

    2009-03-15

    In the section World Energy Future of this magazine two articles, two interviews and one column are presented. The article 'A green example to the world' refers briefly to the second World Future Energy Summit in Abu Dhabi, which was held from 18-21 January, 2009. The second article, 'Green Utopia in the desert' attention is paid to the Abu Dhabi government-driven Masdar Initiative. The two interviews concern an interview with BP Alternative Energy ceo Vivienne Cox, and an interview with the founder and CEO of New Energy Finance Michael Liebreich. The column ('An efficient response') focuses on the impact of the economic crisis on energy policy.

  9. The new world disorder.

    Science.gov (United States)

    Checa, Nicolas; Maguire, John; Barney, Jonathan

    2003-08-01

    On January 1, 1995, representatives from 76 countries signed the World Trade Organization charter, which for years had been part of a temporary trade agreement. The WTO's emergence as a fully empowered supranational body seemed to reflect the triumph of what the first President Bush had described as the "new world order." That order was based on two assumptions: that a healthy economy and a sound financial system make for political stability, and that countries in business together do not fight each other. The number one priority of U.S. foreign policy was thus to encourage the former Communist countries of Europe and the developing nations in Latin America, Asia, and Africa to adopt business-friendly policies. Private capital would flow from the developed world into these countries, creating economic growth. It sounded too good to be true, and so it proved. The new world order of Bush père and his successor, Bill Clinton, has been replaced by the new world disorder of Bush fils. Under the second Bush's administration, the economic and political rationale-behind the Washington consensus of the 1990s has unraveled, forcing a radical change in our perceptions of which countries are safe for business. Negotiating this new environment will require companies to more rigorously evaluate political events and more carefully assess the links between political, economic, and financial risk factors. They'll need to be more selective about which markets to enter, and they'll need to think differently about how to position themselves in those markets. The geopolitical events of the past year, the Bush administration's global war on terror, as well as ongoing convulsions in traditional political and economic relationships must be understood and managed by corporate leaders worldwide. With careful analysis, business leaders can increase their companies' visibility and better respond to the uncertainties of the new world disorder.

  10. The world of Edgerank

    DEFF Research Database (Denmark)

    Carlsen, Hjalmar Alexander Bang; Birkbak, Andreas

    2016-01-01

    marketing blogs about how to handle the algorithm in practice. Based on these events, we construct an ‘internalistic’ account of the rhetoric of Edgerank, opening for an exploration of its moral grammar and the world or dwelling place it assumes and enacts. We find that the world of Edgerank is ordered...... do so by examining three specific situations where the operations of Edgerank have been critiqued and defended: First, Facebook’s own response to the critique that social media produce echo chambers. Second, Facebook’s presentation of the main variables in the Edgerank algorithm. Third, social media...

  11. The World of Wars

    DEFF Research Database (Denmark)

    Harste, Gorm

    2014-01-01

    The world of the future will not be one without wars. The many hopes we have about a future peace governed by a more or less confederal state will not make wars obsolete. Regular wars and irregular wars will continue and probably about different subjects than we are used to. The article proposes...... that the form of war will be more about temporalities, i.e. fast interchanges or, rather, more risky protracted wars of attrition and exhaustion and less about tactical well defined territories. The West can neither dominate such wars nor establish one world that is ruled or even governed. The risk is that we...

  12. World championship in negotiation?

    DEFF Research Database (Denmark)

    Smolinski, Remigiusz; Kesting, Peter

    2013-01-01

    The last decade has seen the emergence of several new negotiation competitions around the world.We think the two major drivers of this development are a general trend toward the increasing internationalization of higher education and a recognition of the specific benefits of competitions for nego......The last decade has seen the emergence of several new negotiation competitions around the world.We think the two major drivers of this development are a general trend toward the increasing internationalization of higher education and a recognition of the specific benefits of competitions...

  13. Inside-My-World

    Directory of Open Access Journals (Sweden)

    Clemens Fessler

    2012-03-01

    Full Text Available Inside-My-World ist die erste Offline-Plattform, auf der man Freundinnen und Freunde kennenlernen, sich im Chat oder in Foren unterhalten, spannende Games spielen oder ganz einfach das eigene Profil gestalten und auf die Pinnwand seiner Freundinnen und Freunde schreiben kann.Diese Plattform hat den Vorteil, dass zum Einstieg keine Computer und keine Internetverbindung notwendig sind, da sie in jedem Raum, z.B. in einem Klassenzimmer, entstehen kann. Denn Inside-My-World ist ein Soziales Netzwerk in Form eines Rollenspiels für Gruppen, z.B. SchülerInnen, LehrerInnen oder Eltern.

  14. [Towards an urban world].

    Science.gov (United States)

    1991-12-01

    It has been estimated that by the year 2006, the proportion of the world's population residing in cities will for the 1st time exceed 50%. The entire urban population will be living on 1% of the earth's surface. Rapid growth of cities is largely limited to developing countries, where about 9/10 of urban growth is expected to occur in coming decades. Urban growth in developing countries is due to high fertility as well as inmigration of poor peasants seeking a better life. The current growth rate of Third World cities is 3.6% annually, which signifies doubling of the population in 20 years. Paris required over a century to grow from 547,000 to 3 million, but Lagos grew from 700,000 to 5.6 million in 20 years and Cairo grew by 6.5 million in 34 years. Immoderate population growth places a great strain on cities attempting to provide basic services. Only a few authoritarian governments have succeeded in limiting immigration to their metropolitan areas. Rapidly growing cities have become symbols not only of poverty and social deterioration, but of ecological destruction, contamination, and lack of health. Air pollution, waste management, and the water supply are 3 of the most serious problems of hygiene and sanitation in the world's cities. Air pollution is caused by various factors including car exhausts and coal burning. According to World Health Organization data, less than 60% of Third World housing has access to an adequate sanitary system. 90% of sewage is not treated before elimination. And millions of persons with no potable water supply are obliged to consume contaminated water or to use their scarce resources to buy water. Many cities lose up to 60% of their scarce water supplies through leaking pipes. If these pipes were repaired, and the loss amounted to the 12% typical of the US and Great Britain, this single measure would double the volume of potable water available. The lack of social balance is at the root of urban problems in the Third World. 600

  15. Engaged World-Making

    DEFF Research Database (Denmark)

    Robertson, Maria Louise Bønnelykke; Rubow, Cecilie

    2013-01-01

    Drawing on fieldwork in Kiribati and the Cook Islands, this chapter shows how atoll islands and tropical lagoons, considered highly vulnerable to present and future sea level rise, are extraordinary malleable socio-natural worlds. Revolving around sacred islands submerged by sea water, ancient fish...... traps, whales, coastal protection devices, and scientific findings of sand sedimentation processes and sea level rise, we demonstrate how the island worlds are constantly made and remade by social and natural forces, and somewhat surprisingly, how the rising sea is conspicuously absent at many island...

  16. The World of Rice

    Institute of Scientific and Technical Information of China (English)

    VALERIE SARTOR

    2010-01-01

    @@ Pilafs, risottos, soups, snacks, paellas,stuffing, vinegars, wines and desserts-rice is used all over the world in myriad ways as food and drink.Although rice is one of the world's most ancient foods and it is impossible to know exactly where and when cultivation of this marvelous grain began, China is popularly acknowledged as the homeland of rice. Chinese people have many legends about rice. Some describe a benevolent goddess in silk robes whose gown accidentally picked up stray rice grains, which she dropped from the heavens to humans below. It's also said that Shennong, the Divine Farmer in Chinese myth, sowed the first rice on earth.

  17. Suicide in the World

    Directory of Open Access Journals (Sweden)

    Peeter Värnik

    2012-03-01

    Full Text Available Introduction: Over the past 20 years the WHO has considerably improved world mortality data. There are still shortcomings but more countries now report data and world-wide estimates are regularly made. Methods: Data about mortality have been retrieved from the WHO world database. Worldwide injury mortality estimates for 2008 as well as trends of the suicide rate from 1950 to 2009 were analysed. Results: Suicides in the world amount to 782 thousand in 2008 according to the WHO estimate, which is 1.4% of total mortality and 15% of injury mortality. The suicide rate for the world as a whole is estimated at 11.6 per 100,000 inhabitants. The male–female rate ratio of suicide is estimated to be highest in the European Region (4.0 and the lowest in the Eastern Mediterranean region (1.1. Among males the highest suicide rate in the 15–29 age group is in the SE Asian region, in the 45–59 age group in European males and for ages above 60 in the Western Pacific region. Females from SE Asia have a remarkably high suicide rate among 15–29-year-olds and from age 45 in the Western Pacific region. The leading country is currently Lithuania, with a suicide rate of 34.1 per 100,000 inhabitants. Also among males the suicide rate is the highest in Lithuania at 61.2. Among females South Korea with 22.1 is at the top of world suicide rates. Conclusions: During the past six decades, according to the WHO Japan, Hungary, and Lithuania have topped the list of world countries by suicide rate, but if the current trends continue South Korea will overtake all others in a few years. The heart of the problem of suicide mortality has shifted from Western Europe to Eastern Europe and now seems to be shifting to Asia. China and India are the biggest contributors to the absolute number of suicides in the world.

  18. Real-World Experiences

    Science.gov (United States)

    Borja, Rhea R.

    2006-01-01

    This article presents IISME, a U.S. program that can give educators a real-world experience and that can deepen their subject-matter knowledge. It also presents the experiences of some teachers who are into this program. IISME's summer-fellowship program started out with 40 teachers and 12 companies. The group's growth picked up in 2001, when it…

  19. To Impress The World

    Institute of Scientific and Technical Information of China (English)

    ZHANG ZHIPING

    2010-01-01

    @@ An Exhibition of Fine Works of Seal Engraving Art was held in the Cultural Center of the World Expo in Shanghai in mid-August. The exhibition was organized by the Chinese Academy of Seal Engraving of the Chinese Academy of Arts.

  20. Entertaining the whole world

    NARCIS (Netherlands)

    Cheok, Adrian David; Nijholt, Anton; Romão, Teresa

    2014-01-01

    Entertainment media are entertainment products and services that rely on digital technology. Mostly the digital entertainment industry is focused on the developed world such as USA, Europe, and Japan. However, due to the decreasing cost of computer and programming technologies, developing countries

  1. World wide biomass resources

    NARCIS (Netherlands)

    Faaij, A.P.C.

    2012-01-01

    In a wide variety of scenarios, policy strategies, and studies that address the future world energy demand and the reduction of greenhouse gas emissions, biomass is considered to play a major role as renewable energy carrier. Over the past decades, the modern use of biomass has increased rapidly in

  2. French in Culinary World

    Directory of Open Access Journals (Sweden)

    Rila Hilma

    2011-09-01

    Full Text Available More than million foods have been made by people from all over the world in the latest years. People now try to create new cooks and make some creativity on it. Then, cooking which the field is culinary has become an art because it needs an artistic value to decorate the food, a good taste and proper technique in processing delicious food in order to make it a masterpiece. French culinary is as famous as the Eiffel tower in the heart of the country, Paris. Most of fine dining international restaurants apply the French menu and cooking. This article presents an overview about the French element in culinary world; starts from its history, kitchen organization, French menu spelling, and French cooking vocabulary. The discussion proceeds library research to compile the data. Later, the art of culinary is interesting to be learned because it contains the classical history of world civilization, in this case French civilization. The issue of cooking trend nouvelle cuisine was a masterpiece of one of the greatest chef in his time, Escoffier. French culinary is widely well-known in all over the world because of innovation, creativity, and proud. Those are spirits that we must learn.

  3. Brane world scenarios

    Indian Academy of Sciences (India)

    Dileep P Jatkar

    2003-02-01

    We review proposals of brane world models which attempt to combine gauge theories with gravity at TeV scale by confining the gauge theory to a three-brane embedded in higher dimensional bulk. Gravity, however, propagates in the directions transverse to the brane as well.

  4. Withdrawn Amidst the World

    DEFF Research Database (Denmark)

    Bruun, Mette Birkedal; Nørgaard, Lars Cyril; Nagelsmit, Eelco

    2017-01-01

    The pious Élisabeth d'Orléans, Mme de Guise, had a vivid correspondence with Armand-Jean de Rancé, abbot of the Cistercian abbey of La Trappe in Normandy. Rancé was considered a champion of unconditional isolation from the world by his contemporaries, but in fact he recommended quite diverse forms...... in remarkable detail how the Duchess should balance her obligations to God and human beings by being a model of withdrawal. To this end she must constantly, in action and demeanour, display to the world her withdrawal from the world. Rancé's spiritual advice to Mme de Guise throws new light on the devotional...... horizon of Gaston d'Orléans's daughter and the pastoral practice of the abbot of La Trappe. Above all, it shows the intricacies and modulations of the withdrawal from the world prescribed to late seventeenth-century aristocratic dévots and, especially, dévotes....

  5. Affective World Literature

    DEFF Research Database (Denmark)

    Vilslev, Annette Thorsen

    The PhD dissertation compares the literary theory and novels of modern Japanese writer Natsume Sōseki. It reads Sōseki’s Theory of Literature (2009, Bungakuron, 1907) as an inherently comparative and interdisciplinary approach to theorizing feelings in world literature. More broadly, the disserta......The PhD dissertation compares the literary theory and novels of modern Japanese writer Natsume Sōseki. It reads Sōseki’s Theory of Literature (2009, Bungakuron, 1907) as an inherently comparative and interdisciplinary approach to theorizing feelings in world literature. More broadly......, the dissertation investigates the critical negotiation of the novel as a travelling genre in Japan in the beginning of the 20th century, and, more specifically, Sōseki’s work in relation to world literature and affect theory. Sōseki’s work is highly influential in Japan and East Asia, and his novels widely...... circulated beyond Japan. Using Sōseki’s theory as an example, and by comparing it to other theories, the dissertation argues that comparative literature needs to include not only more non-Western literature but also more non-Western literary theories in the ongoing debate of world literature. Close...

  6. World beyond Pluto

    CERN Document Server

    Marlowe, Stephen

    2014-01-01

    What happens when a hardened criminal on the run for his life gets mixed up with an all-girl symphony traveling between lesser-populated planets in a futile attempt to bring culture to their rowdy inhabitants? Well, to put it mildly, hijinks ensue. Read Stephen Marlowe's thoroughly entertaining World Beyond Pluto to find out the rest.

  7. World Security and Equity

    NARCIS (Netherlands)

    J. Tinbergen (Jan)

    1990-01-01

    textabstractA very neat illustration of the skilful use of small, manageable, world models to consider pressing policy questions of great current relevance. Ron Smith, The Economic Journal" Jan Tinbergen, in this book as in his earlier work, has the courage to address central issues. Dietrich

  8. Dancing With the World

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Ballet, the dance created for court performances in Renaissance Europe that reached into the world of high art in early 17th century France, has long been loved by Chinese. As early as the 1920s, andinto the 1950s and 1960s when the country was alienated from the

  9. Globalization and world trade

    Science.gov (United States)

    Peter J. Ince; Joseph Buongiorno

    2007-01-01

    This chapter discusses economic globalization and world trade in relation to forest sector modeling for the US/North American region. It discusses drivers of economic globalization and related structural changes in US forest product markets, including currency exchange rates and differences in manufacturing costs that have contributed to the displacement of global...

  10. Exploring New Geometric Worlds

    Science.gov (United States)

    Nirode, Wayne

    2015-01-01

    When students work with a non-Euclidean distance formula, geometric objects such as circles and segment bisectors can look very different from their Euclidean counterparts. Students and even teachers can experience the thrill of creative discovery when investigating these differences among geometric worlds. In this article, the author describes a…

  11. French in Culinary World

    Directory of Open Access Journals (Sweden)

    Rila Hilma

    2011-10-01

    Full Text Available More than million foods have been made by people from all over the world in the latest years. People now try to create new cooks and make some creativity on it. Then, cooking which the field is culinary has become an art because it needs an artistic value to decorate the food, a good taste and proper technique in processing delicious food in order to make it a masterpiece. French culinary is as famous as the Eiffel tower in the heart of the country, Paris. Most of fine dining international restaurants apply the French menu and cooking. This article presents an overview about the French element in culinary world; starts from its history, kitchen organization, French menu spelling, and French cooking vocabulary. The discussion proceeds library research to compile the data. Later, the art of culinary is interesting to be learned because it contains the classical history of world civilization, in this case French civilization. The issue of cooking trend “nouvelle cuisine” was a masterpiece of one of the greatest chef in his time, Escoffier. French culinary is widely well-known in all over the world because of innovation, creativity, and proud. Those are spirits that we must learn.   

  12. Mapping a Changing World.

    Science.gov (United States)

    Stoltman, Joseph P.

    1992-01-01

    Addresses the importance of maps for instruction in both history and geography. Suggests that maps have gotten recent attention because of the rapid political changes occurring in Europe and the quincentenary of Columbus' voyage. Discusses different map projections and the importance of media and satellite display of real pictures of the world.…

  13. World wide biomass resources

    NARCIS (Netherlands)

    Faaij, A.P.C.

    2012-01-01

    In a wide variety of scenarios, policy strategies, and studies that address the future world energy demand and the reduction of greenhouse gas emissions, biomass is considered to play a major role as renewable energy carrier. Over the past decades, the modern use of biomass has increased rapidly in

  14. World Collection of Cotton

    Institute of Scientific and Technical Information of China (English)

    KHAKIMJON Saydaliyev; ALISHER Amanturdiev; MALOXAT Halikova

    2008-01-01

    @@ Achievements of selection and other theoretical researches on cotton not only in our country,but also world-wide depend on the presence of genetic resources.Uzbek Scientific Research Institute of Selection and Seed Growing of Cotton is a leading center of science on breeding and production of cotton across Central Asia.

  15. Searching for world domination

    CERN Multimedia

    Quillen, E

    2004-01-01

    "Optimists might believe Microsoft suffered a setback last week that will impede its progress toward world domination, but I suspect the company has already found a way to prevail. At issue before the European Union was Microsoft's bundling of its Windows Media Player with its operating system" (1 page)

  16. World Database of Happiness

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1995-01-01

    textabstractABSTRACT The World Database of Happiness is an ongoing register of research on subjective appreciation of life. Its purpose is to make the wealth of scattered findings accessible, and to create a basis for further meta-analytic studies. The database involves four sections:
    1.

  17. The World of Wars

    DEFF Research Database (Denmark)

    Harste, Gorm

    2014-01-01

    The world of the future will not be one without wars. The many hopes we have about a future peace governed by a more or less confederal state will not make wars obsolete. Regular wars and irregular wars will continue and probably about different subjects than we are used to. The article proposes ...

  18. World Heart Day

    Centers for Disease Control (CDC) Podcasts

    2009-09-01

    For World Heart Day, learn more about what heart-healthy steps you can take in the workplace.  Created: 9/1/2009 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 9/9/2009.

  19. World Security and Equity

    NARCIS (Netherlands)

    J. Tinbergen (Jan)

    1990-01-01

    textabstractA very neat illustration of the skilful use of small, manageable, world models to consider pressing policy questions of great current relevance. Ron Smith, The Economic Journal" Jan Tinbergen, in this book as in his earlier work, has the courage to address central issues. Dietrich Fisher

  20. World wide biomass resources

    NARCIS (Netherlands)

    Faaij, A.P.C.

    2012-01-01

    In a wide variety of scenarios, policy strategies, and studies that address the future world energy demand and the reduction of greenhouse gas emissions, biomass is considered to play a major role as renewable energy carrier. Over the past decades, the modern use of biomass has increased

  1. World Database of Happiness

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1995-01-01

    textabstractABSTRACT The World Database of Happiness is an ongoing register of research on subjective appreciation of life. Its purpose is to make the wealth of scattered findings accessible, and to create a basis for further meta-analytic studies. The database involves four sections:
    1. Bib

  2. World Database of Happiness

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1995-01-01

    textabstractABSTRACT The World Database of Happiness is an ongoing register of research on subjective appreciation of life. Its purpose is to make the wealth of scattered findings accessible, and to create a basis for further meta-analytic studies. The database involves four sections:
    1. Bib

  3. Worlds of Meaning.

    Science.gov (United States)

    Perlin, Ruth R.

    1998-01-01

    Summarizes the lives and pursuits of four U.S. artists: Winslow Homer, John Frederick Peto, George Bellows, and Joan Mitchell. Explains the concepts apparent in the four works of art and shows how the artists created these works through expressing their perceptions of the world around them. Lists questions for further exploration. (CMK)

  4. An interdependent world

    Institute of Scientific and Technical Information of China (English)

    金碚

    2009-01-01

    The financial crisis that first struck the United States is unfolding into a worldwide economic recession.When the U.S.coughs,the world catches a cold,now a once-in-acentury cold.This is unexpected to most people,including most economists.It is often said that everything in the

  5. The World Science Festival

    Science.gov (United States)

    Pazmino, J.

    2012-06-01

    (Abstract only) New York City in the late 20th century rose to be a planetary capital for the sciences, not just astronomy. This growth was mainly in the academic sector but a parallel growth occurred in the public and home field. With the millennium crossing, scientists in New York agitated for a celebration of the City as a place for a thriving science culture. In 2008 they began World Science Festival. 2011 is the fourth running, on June 1-5, following the AAVSO/AAS meetings. World Science Festival was founded by Dr. Brian Greene, Columbia University, and is operated through the World Science Foundation. The Festival is "saturation science" all over Manhattan in a series of lectures, shows, exhibits, performances. It is staged in "science" venues like colleges and musea, but also in off-science spaces like theaters and galleries. It is a blend from hard science, with lectures like those by us astronomers, to science-themed works of art, dance, music. Events are fitted for the public, either for free or a modest fee. While almost all events are on Manhattan, effort has been made to geographically disperse them, even to the outer boroughs. The grand finale of World Science Festival is a street fair in Washington Square. Science centers in booths, tents, and pavilions highlight their work. In past years this fair drew 100,000 to 150,000 visitors. The entire Festival attracts about a quarter-million attendees. NYSkies is a proud participant at the Washington Square fair. It interprets the "Earth to the Universe" display, debuting during IYA-2009. Attendance at "Earth..." on just the day of the fair plausibly is half of all visitors in America. The presentation shows the scale and scope of World Science Festival, its relation to the City, and how our astronomers work with it.

  6. Economics: An Emerging Small World?

    NARCIS (Netherlands)

    S. Goyal (Sanjeev); M.J. van der Leij (Marco); J.L. Moraga-Gonzalez (José Luis)

    2004-01-01

    textabstractThis paper examines the small world hypothesis. The first part of the paper presents empirical evidence on the evolution of a particular world: the world of journal publishing economists during the period 1970-2000. We find that in the 1970's the world of economics was a collection of is

  7. Learning Experience with Virtual Worlds

    Science.gov (United States)

    Wagner, Christian

    2008-01-01

    Virtual worlds create a new opportunity to enrich the educational experience through media-rich immersive learning. Virtual worlds have gained notoriety in games such as World of Warcraft (WoW), which has become the most successful online game ever, and in "general purpose" worlds, such as Second Life (SL), whose participation levels (more than 10…

  8. Virtual World Astrosociology

    Science.gov (United States)

    Bainbridge, William Sims

    2010-01-01

    This essay introduces the opportunity for theory development and even empirical research on some aspects of astrosociology through today's online virtual worlds. The examples covered present life on other planets or in space itself, in a manner that can be experienced by the user and where the user's reactions may simulate to some degree future human behavior in real extraterrestrial environments: Tabula Rasa, Anarchy Online, Entropia Universe, EVE Online, StarCraft and World of Warcraft. Ethnographic exploration of these computerized environments raises many questions about the social science both of space exploration and of direct contact with extraterrestrials. The views expressed in this essay do not necessarily represent the views of the National Science Foundation or the United States.

  9. World energy outlook 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-11-07

    The World Energy Outlook 2006 sets out the IEA's latest projections of world energy supply and demand to 2030 for oil, gas, coal, renewables, nuclear and electricity, plus projections on energy-related CO{sub 2} emissions. The publication is in three parts. Part A: The reference scenario has chapters entitled: Key assumptions; Global Energy Trends; Oil market outlook; Gas market outlook; Coal market outlook; and Power sector outlook. Part B: The alternative policy scenario contains chapters on: Mapping a new energy future; Assessing the cost-effectiveness of alternative policies; Deepening the analysis results by sector; and Getting to and going beyond the alternative policy scenario. Part C: Focus on key topics contains: The impact of higher energy prices; Current trends in oil and gas investment; Prospects for nuclear power; The outlook for biofuels; Energy for coking in developing countries; and Focus on Brazil. 224 figs., 84 tabs., 5 annexes.

  10. World Class Facilities Management

    DEFF Research Database (Denmark)

    Malmstrøm, Ole Emil; Jensen, Per Anker

    2013-01-01

    Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet.......Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet....

  11. World energy insight

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-15

    The 21st World Energy Congress offers a unique opportunity for all stake-holders of the energy sector to meet and exchange visions, strategies and practices, during four days of very intensive and interesting sessions, round-tables and exhibitions. More than 3,000 energy leaders gather from around the world from both developed and developing countries, from all types of energy, from public and private companies and government organisations, in order to think together about how to bring about a sustainable and acceptable energy future. The truth is that nobody has the choice any longer. All energy leaders have to take decisions every day, and they need to have a clear analysis of what is at stake, what the risks are, and what the solutions can be.

  12. Militarism and world health.

    Science.gov (United States)

    Kiefer, C W

    1992-04-01

    Militarism is a rapidly growing factor in that complex network of social, political and economic causes of ill health among the world's poor. This complex of causes is driving a spiral of class inequality, political instability, and military repression in many less developed nations. These nations share a uniform security doctrine, which has major health impacts. Here five impacts are noted: diversion of resources, suppression of dissent, military classism, environment damage, and crime and terrorism. The demand stimulated by the recent Persian Gulf War for expensive, high-technology weapons may deepen Third World debt and fuel the cycle of poverty, ill health, social unrest, and military oppression. International health workers need to take account of the causes and effects of militarism in their studies of health problems. Their work could be aided by organizations that promote disarmament and environment preservation.

  13. World Class Facilities Management

    DEFF Research Database (Denmark)

    Malmstrøm, Ole Emil; Jensen, Per Anker

    2013-01-01

    Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet.......Alle der med entusiasme arbejder med Facilities Management drømmer om at levere World Class. DFM drømmer om at skabe rammer og baggrund for, at vi i Danmark kan bryste os at være blandt de førende på verdensplan. Her samles op på, hvor tæt vi er på at nå drømmemålet....

  14. Brave nuclear world

    Energy Technology Data Exchange (ETDEWEB)

    Pockley, P

    1999-05-01

    Two announcements have confirmed that the current Australian government intends to realize the unfulfilled dream of the Menzies era for Australia to become a `nuclear nation` by approving a new `research reactor` and a new uranium mine. Meanwhile, the government is working hard to overturn UNESCO`s recommendation to stop the development of the Jabiluka uranium mine. And, an international proposal to store in Australia stockpiles of high level waste from the world`s power stations and decommissioned nuclear weapons has finally come into the open with the revelation that Pangea Resources Australia Pty Ltd has presented a summary proposal to the government. Though rejected, the plan remains active. Central to the rush to capitalise on Australia`s uranium resources is Environment Minister, Senator Robert Hill, whose formal approvals for the reactor and the mine have been legally essential

  15. World Development Report 2004

    OpenAIRE

    World Bank

    2003-01-01

    Too often, services fail poor people in access, in quality, and in affordability. But the fact that there are striking examples where basic services such as water, sanitation, health, education, and electricity do work for poor people means that governments and citizens can do a better job of providing them. Learning from success and understanding the sources of failure, this year’s World Development Report, argues that services can be improved by putting poor people at the center of service ...

  16. Modeling the World

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Chinese models still have a long way to go A Chinese debutante garnered most of the limelight at the annual Victoria’s Secret Fashion Show in New York in November last year. He Sui, a newcomer to the modeling world, was the focus of many photographers as the dark haired beauty walked down the runway in a mermaid inspired ensemble.He was followed by another Chinese

  17. The world of particles

    CERN Document Server

    Southworth, Brian

    1991-01-01

    What is our Universe made of? Where does it come from? Why does it behave as it does? We do not have all the answers to these questions but in recent years we have uncovered a lot of information about the Universe which surrounds us. This search has revealed that, beyond the evidence of our eyes, there is a seething world of tiny particles and messengers which pass between them...

  18. World Presidents Organization

    Science.gov (United States)

    2010-01-01

    Members of the World Presidents' Organization take a try at 'piloting' a mock-up of the space shuttle cockpit during a Jan. 26 visit to StenniSphere, the museum and visitor center at NASA's John C. Stennis Space Center. WPO members from several states spent the day touring Stennis facilities and learning about the work of the nation's premier rocket engine testing site.

  19. WORLD MERCHANDISE TRADE

    Directory of Open Access Journals (Sweden)

    Serghei MĂRGULESCU

    2017-05-01

    Full Text Available This article is mainly based on the most recent statistical data of the World Trade Organization and some aspects related to the evolution of world merchandise trade, in terms of volume and value, in 2015. The volume of world merchandise trade continued to grow slowly in 2015 while the dollar value of it declined sharply as exports fell 14 per cent to US$ 16 trillion, down from US$ 19 trillion in the previous year. It presents also the contribution of the volume change and of the change in unit values (which account for fluctuations in prices and exchange rates to the value trade growth (in current dollar terms. The discrepancy between trade growth in 2015 in terms of volume and value was mostly attributable to swings in commodity prices and exchange rates The course of economic globalization is also shortly looked on based on some data and considerations of Credit Suisse analysts. Three different scenarios were taken into account in this respect. First one in which globalization continues in the form we know it over the past thirty years, second one in which a multipolar world is a better representation of the state of affairs and third, a scenario in which globalization ends due to the rise of anti-globalization political movements. The second scenario seems to provide a better reflection of reality today, despite the fact that a certain slowdown is observable when taking into account the diminishing growth rate of physical trade, the slower penetration of foreign assets of the developed market companies and signs of reshoring of some business back home. Globalization remains intact in terms of consumption and marketing patterns, while companies seem more reluctant to invest abroad.

  20. People in the World

    Institute of Scientific and Technical Information of China (English)

    方岩

    2004-01-01

    “When in Rome, do as the Romans do.”is a famous saying about customs. But what exactly do the Romans and other people do that is so different? Where do women wear tings in their noses to show they are married, for example? Where do people greet each other with a bow rather than a handshake? Here are some other ways people behave and beautify themselves around the world.

  1. World Development Report 2015

    OpenAIRE

    World Bank Group

    2014-01-01

    Every policy relies on explicit or implicit assumptions about how people make choices. Those assumptions typically rest on an idealized model of how people think, rather than an understanding of how everyday thinking actually works. This year’s World Development Report argues that a more realistic account of decision-making and behavior will make development policy more effective. The Report emphasizes what it calls 'the three marks of everyday thinking.' In everyday thinking, people use...

  2. World Presidents Organization

    Science.gov (United States)

    2010-01-01

    Members of the World Presidents' Organization enjoy a buffet luncheon during a Jan. 26 visit to NASA's John C. Stennis Space Center. WPO members from several states toured Stennis facilities during a daylong visit that included a river ride with Special Boat Team 22, the U.S. Navy's elite boat warriors group that trains at Stennis. Visiting president also had an opportunity to learn about the ongoing work of the nation's premier rocket engine testing site.

  3. Diamantina: World Cultural Heritage

    Directory of Open Access Journals (Sweden)

    Fernanda de Alencar Machado Albuquerque

    2012-11-01

    Full Text Available Awareness on preservation of cultural values in Brazil has been characterized as a current trend, and local communities play an important role in this process. The country’s preservationist policy has emerged with the Institute of National Historical and Artistic Heritage that aims at identifying and preserving the historical, cultural and artistic heritage. In the Brazilian scene the city of Diamantina/MG stands out for its remarkable cultural heritage, considered by UNESCO a World Cultural Heritage.

  4. Trust and virtual worlds

    DEFF Research Database (Denmark)

    Ess, Charles; Thorseth, May

    2011-01-01

    We collect diverse philosophical analyses of the issues and problems clustering around trust online with specific attention to establishing trust in virtual environments. The book moves forward important discussions of how virtual worlds and virtuality are to be defined and understood; the role o...... by virtuality, such as virtual child pornography. The introduction further develops a philosophical anthropology, rooted in Kantian ethics, phenomenology, virtue ethics, and feminist perspectives, that grounds a specific approach to ethical issues in virtual environments....

  5. World Natural Gas Model

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-01

    RAMSGAS, the Research and Development Analysis Modeling System World Natural Gas Model, was developed to support planning of unconventional gaseoues fuels research and development. The model is a scenario analysis tool that can simulate the penetration of unconventional gas into world markets for oil and gas. Given a set of parameter values, the model estimates the natural gas supply and demand for the world for the period from 1980 to 2030. RAMSGAS is based on a supply/demand framwork and also accounts for the non-renewable nature of gas resources. The model has three fundamental components: a demand module, a wellhead production cost module, and a supply/demand interface module. The demand for gas is a product of total demand for oil and gas in each of 9 demand regions and the gas share. Demand for oil and gas is forecast from the base year of 1980 through 2030 for each demand region, based on energy growth rates and price-induced conservation. For each of 11 conventional and 19 unconventional gas supply regions, wellhead production costs are calculated. To these are added transportation and distribution costs estimates associated with moving gas from the supply region to each of the demand regions and any economic rents. Based on a weighted average of these costs and the world price of oil, fuel shares for gas and oil are computed for each demand region. The gas demand is the gas fuel share multiplied by the total demand for oil plus gas. This demand is then met from the available supply regions in inverse proportion to the cost of gas from each region. The user has almost complete control over the cost estimates for each unconventional gas source in each year and thus can compare contributions from unconventional resources under different cost/price/demand scenarios.

  6. View on world market

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, J. [Vestas Wind Systems A/S, Lem (Denmark)

    1996-12-31

    Opinions on the world market for wind power are presented in this paper. Reasons contributing to a potential growth in wind power are cited. Increased demand is expected to arise due to increased energy needs and environmental concerns. Barriers, primarily political, to the development of wind energy are assessed. Development is predicted to occur first in countries with a demand for new capacity and political decisions to protect the environment.

  7. The world's children.

    Science.gov (United States)

    Niimi, R

    1997-01-01

    World leaders from 159 countries agreed at the 1990 World Summit for Children to specific goals which would reduce levels of child and maternal mortality, and give every child access to basic education, clean water, and proper sanitation by 2000. Major progress has since been achieved in most countries, with more than 80% of the world's children now immunized against diphtheria, tetanus, and pertussis. Moreover, the deaths of over 1 million children annually are being averted through the increased use of oral rehydration therapy against diarrheal dehydration, poliomyelitis and guinea worm have almost been eradicated, the consumption of iodized salt is protecting approximately 12 million infants annually from iodine deficiency, and access to safe drinking water is on the rise. Scientific developments in pediatrics, the strengthening of national health services, and the use of cost-effective primary health care approaches such as immunization, oral rehydration therapy, the promotion of breast feeding, and growth monitoring have helped reduce the national rate of infant mortality (IMR) in Turkey to 42 per 1000 live births compared to the urban IMR in Turkey during the 1940s of 300-350/1000. Developments in public health, the Convention on the Rights of the Child (CRC), education and child development, and child protection and the CRC are discussed.

  8. General Environment Of World

    Directory of Open Access Journals (Sweden)

    Dr. Mohammed Viquaruddin

    2012-11-01

    Full Text Available This paper is an attempt regarding the general social/economical/ecological/political and more environments of world certainly with multidisciplinary/interdisciplinary approach. It is discussed that the problems of fore further can besolved through facts/reasoning/science/environment/social sciences etc. As beinga student of political science even peace science a try that can come into existenceor can be practiced only through many dimensions. The philosophy is developedto resist with whatever means we have in hand and are willing to fight for a betterscenario which would be something out of our reach! But can achieve through apositive and plural system not certainly perfect but different in its approach.Achievement to the threats and problems to the liberal vision are pervasive and thesystem is in much greater problematic that is commonly supposed. Protecting/Preserving/ Commanding it in the coming century and beyond will be easier saidthan done! We do not foresee the renaissance of any type we should be sure aboutthat alternative World Multidimensional System (WMS could reasonably competewith the present multidimensional system on theoretical or practical grounds. It isnot enough that this system display substantial practical advantages and genuinetheoretical coherence. No one can deny that world get profit from present system.

  9. Intersecting Brane Worlds

    CERN Document Server

    Aldazabal, G; Ibáñez, L E; Rabadan, Raul; Uranga, Angel M

    2001-01-01

    It is known that chiral fermions naturally appear at certain intersections of branes at angles. Motivated by this fact, we propose a string scenario in which different standard model gauge interactions propagate on different (intersecting) brane worlds, partially wrapped in the extra dimensions. Quarks and leptons live at brane intersections, and are thus located at different positions in the extra dimensions. Replication of families follows naturally from the fact that the branes generically intersect at several points. Gauge and Yukawa couplings can be computed in terms of the compactification radii. Hierarchical Yukawa couplings appear naturally, since amplitudes involving three different intersections are proportional to exp(-A_{ijk}), where A_{ijk} is the area of a string world-sheet extending among the intersections. The models are non-supersymmetric but the string scale may be lowered down to 1-10 TeV. The proton is however stable due to a set of discrete symmetries arising from world-sheet selection r...

  10. World Standards Day and Its Contribution to the World

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The World Standards Day began in 1970.From 1986,ISO President started to deliver a speech to the world onthe World Standards Day.From 1988,IEC President and ISO President jointly delivered the speech for the World Standards Day.From 1993,the ITU SecretaryGeneral also joined them for the speech on World Standards Day.The 3 most influential international standardization organizations have jointly promoted the World Standards Day,and the theme of every year's speech clearly suggests the development course and trend of standardization.

  11. The World Heritage Centr

    Directory of Open Access Journals (Sweden)

    Ayman G. Abdel Tawab

    2014-09-01

    Full Text Available New Gourna Village, which is located inside one of the World Heritage Sites in Egypt, has never been recognized as an element contributing to the site’s Outstanding Universal Value. The recognition of the village as a contributing element is reliant on the successful assessment of its authenticity and integrity. Responding to the dramatically declining integrity of the village, the World Heritage Centre has carried out an architectural study to guide the potential conservation works in the property. The study has recommended that a group of objectives and two approaches to the conservation of the village should be adopted. One of these two approaches has been concerned with the conservation of the village according to the architect’s original intentions and principles. The previous approach can be called the principles-based approach. The main aim of this study was to examine the agreement of the World Heritage Centre’s objectives and their proposed principles-based approach to the conservation of the village with the aim to improve its chance in meeting the conditions of authenticity and integrity. The study approached the previous aim by assessing, by means of a proposed methodology; the level of significance, authenticity and integrity of the property. Based on the previous assessment, a list of conservation interventions was proposed to improve the property’s chance in meeting the conditions of authenticity and integrity. Finally, the World Heritage Centre’s recommended approaches and objectives were examined against the previous proposed conservation interventions. The findings indicated the possibility to adopt the principles-based approach to the conservation of New Gourna Village, as well as the other World Heritage Centre’s objectives, without limiting the property’s chance in meeting the conditions of authenticity and integrity. The study recommends to carry out further studies that are concerned with the identification

  12. World Energy Outlook 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-11-07

    The 2008 report provides invaluable analysis to help policy makers around the world assess and address the challenges posed by worsening oil supply prospects, higher energy prices and rising emissions of greenhouse gases. In the WEO-2008 Reference Scenario, which assumes no new government policies, world primary energy demand grows by 1.6% per year on average between 2006 and 2030 - an increase of 45%. This is slower than projected last year, mainly due to the impact of the economic slowdown, prospects for higher energy prices and some new policy initiatives. Demand for oil rises from 85 million barrels per day now to 106 mb/d in 2030 - 10 mb/d less than projected last year. Demand for coal rises more than any other fuel in absolute terms, accounting for over a third of the increase in energy use. Modern renewables grow most rapidly, overtaking gas to become the second-largest source of electricity soon after 2010. China and India account for over half of incremental energy demand to 2030 while the Middle East emerges as a major new demand centre. The share of the world's energy consumed in cities grows from two-thirds to almost three-quarters in 2030. Almost all of the increase in fossil-energy production occurs in non-OECD countries. These trends call for energy-supply investment of $26.3 trillion to 2030, or over 1 trillion US dollars/year. Yet the credit squeeze could delay spending, potentially setting up a supply-crunch that could choke economic recovery. In addition to providing a comprehensive update of long-term energy projections to 2030, WEO-2008 takes a detailed look at the prospects for oil and gas production. Oil will remain the world's main source of energy for many years to come, even under the most optimistic of assumptions about the development of alternative technology. But the sources of oil, the cost of producing it and the prices that consumers will have to pay for it are extremely uncertain. It is far from certain that companies

  13. [Tl(III)(dota)](-): An Extraordinarily Robust Macrocyclic Complex.

    Science.gov (United States)

    Fodor, Tamás; Bányai, István; Bényei, Attila; Platas-Iglesias, Carlos; Purgel, Mihály; Horváth, Gábor L; Zékány, László; Tircsó, Gyula; Tóth, Imre

    2015-06-01

    The X-ray structure of {C(NH2)3}[Tl(dota)]·H2O shows that the Tl(3+) ion is deeply buried in the macrocyclic cavity of the dota(4-) ligand (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate) with average Tl-N and Tl-O distances of 2.464 and 2.365 Å, respectively. The metal ion is directly coordinated to the eight donor atoms of the ligand, which results in a twisted square antiprismatic (TSAP') coordination around Tl(3+). A multinuclear (1)H, (13)C, and (205)Tl NMR study combined with DFT calculations confirmed the TSAP' structure of the complex in aqueous solution, which exists as the Λ(λλλλ)/Δ(δδδδ) enantiomeric pair. (205)Tl NMR spectroscopy allowed the protonation constant associated with the protonation of the complex according to [Tl(dota)](-) + H(+) ⇆ [Tl(Hdota)] to be determined, which turned out to be pK(H)Tl(dota) = 1.4 ± 0.1. [Tl(dota)](-) does not react with Br(-), even when using an excess of the anion, but it forms a weak mixed complex with cyanide, [Tl(dota)](-) + CN(-) ⇆ [Tl(dota)(CN)](2-), with an equilibrium constant of Kmix = 6.0 ± 0.8. The dissociation of the [Tl(dota)](-) complex was determined by UV-vis spectrophotometry under acidic conditions using a large excess of Br(-), and it was found to follow proton-assisted kinetics and to take place very slowly (∼10 days), even in 1 M HClO4, with the estimated half-life of the process being in the 10(9) h range at neutral pH. The solution dynamics of [Tl(dota)](-) were investigated using (13)C NMR spectroscopy and DFT calculations. The (13)C NMR spectra recorded at low temperature (272 K) point to C4 symmetry of the complex in solution, which averages to C4v as the temperature increases. This dynamic behavior was attributed to the Λ(λλλλ) ↔ Δ(δδδδ) enantiomerization process, which involves both the inversion of the macrocyclic unit and the rotation of the pendant arms. According to our calculations, the arm-rotation process limits the Λ(λλλλ) ↔ Δ(δδδδ) interconversion.

  14. Extraordinarily Stretchable All-Carbon Collaborative Nanoarchitectures for Epidermal Sensors

    KAUST Repository

    Cai, Yichen

    2017-06-16

    Multifunctional microelectronic components featuring large stretchability, high sensitivity, high signal-to-noise ratio (SNR), and broad sensing range have attracted a huge surge of interest with the fast developing epidermal electronic systems. Here, the epidermal sensors based on all-carbon collaborative percolation network are demonstrated, which consist 3D graphene foam and carbon nanotubes (CNTs) obtained by two-step chemical vapor deposition processes. The nanoscaled CNT networks largely enhance the stretchability and SNR of the 3D microarchitectural graphene foams, endowing the strain sensor with a gauge factor as high as 35, a wide reliable sensing range up to 85%, and excellent cyclic stability (>5000 cycles). The flexible and reversible strain sensor can be easily mounted on human skin as a wearable electronic device for real-time and high accuracy detecting of electrophysiological stimuli and even for acoustic vibration recognition. The rationally designed all-carbon nanoarchitectures are scalable, low cost, and promising in practical applications requiring extraordinary stretchability and ultrahigh SNRs.

  15. How two-dimensional bending can extraordinarily stiffen thin sheets

    Science.gov (United States)

    Pini, V.; Ruz, J. J.; Kosaka, P. M.; Malvar, O.; Calleja, M.; Tamayo, J.

    2016-07-01

    Curved thin sheets are ubiquitously found in nature and manmade structures from macro- to nanoscale. Within the framework of classical thin plate theory, the stiffness of thin sheets is independent of its bending state for small deflections. This assumption, however, goes against intuition. Simple experiments with a cantilever sheet made of paper show that the cantilever stiffness largely increases with small amounts of transversal curvature. We here demonstrate by using simple geometric arguments that thin sheets subject to two-dimensional bending necessarily develop internal stresses. The coupling between the internal stresses and the bending moments can increase the stiffness of the plate by several times. We develop a theory that describes the stiffness of curved thin sheets with simple equations in terms of the longitudinal and transversal curvatures. The theory predicts experimental results with a macroscopic cantilever sheet as well as numerical simulations by the finite element method. The results shed new light on plant and insect wing biomechanics and provide an easy route to engineer micro- and nanomechanical structures based on thin materials with extraordinary stiffness tunability.

  16. Extraordinarily Prolonged Disease Recurrence in a Granulosa Cell Tumor Patient

    Directory of Open Access Journals (Sweden)

    Lisa N. Abaid

    2010-09-01

    Full Text Available Background: Granulosa cell tumors are rare sex cord stromal lesions that comprise approximately 3% of all ovarian neoplasms. The vast majority of granulosa cell tumors are considered indolent but in spite of aggressive management, delayed recurrence is of significant concern. Case Report: We describe a case involving a 67-year-old woman who presented with abdominal pain, bloody stools, and mild nausea. Following a CT scan of the abdomen and pelvis, a 19-cm pelvic mass was identified. Her prior medical history included a hysterectomy for uterine fibroids 40 years ago and a bilateral salpingo-oophorectomy for a presumed granulosa cell tumor 20 years ago. Final pathology revealed granulosa cell tumor with small bowel mesentery involvement. The patient underwent surgical resection and adjuvant chemotherapy; she is currently doing well. Conclusion: Granulosa cell tumors are considered to be of low malignant potential but they have the capacity to recur, even several years following initial patient management. This case exemplifies the disease’s capacity for prolonged recurrence and further accentuates the significance of long-term follow-up in these patients.

  17. World Bioenergy 2012. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    The conference of 2012 had contributions on the following themes: A: World Pellets 2012, B: Market outlook, C: Energy systems, D: Transportation, E: World biorefinery 2012, F: Sustainable bioenergy day. 52 contributions in A - D. A: World Pellets 2012 is an integrated part of World Bioenergy 2012. A three day 'conference in the conference' covering all aspects of pellets: raw material potentials, innovative pellets production systems, torrefaction, new combustion technologies, trade and market development, health and safety aspects, etc. B) Market outlook: Policy and targets for renewable energy to find an alternative to fossil energy are being put in place, increasing the demand for sustainable modern bioenergy. Global trade and improved logistics open up to the markets. To facilitate international trade in bioenergy commodities, new trading places and indexes are needed, as well as generally accepted standards. Supply and demand must meet to guarantee stable prices. In this session you learn all about current market development, including drivers like incentives and policies. C) Energy Systems: Modern bioenergy is a young industry. Therefore, technical development is rapid, with many new innovations. This session focuses on technical development in the whole bioenergy chain, from harvesting of forest residues to combustion technologies and co-firing. Optimal use of biomass through district heating or cooling - small scale and large scale - and CHP technology for electricity production. D) Transportation: Sustainable transports are one of the key challenges of tomorrow. Can we transport biomass as well as other products sustainably and at what costs? Which are the future fuels for transports and when will biofuels be viewed as profitable? Biofuels for transport are under rapid development with new methods, producers and feedstock entering the markets. The future biofuels will be produced in biorefineries, to increase profitability and optimize feed

  18. Antiretrovirals for developing world.

    Science.gov (United States)

    Adler, M W

    1998-01-24

    The most recent UNAIDS figures indicate that approximately 30 million people are infected with HIV worldwide, 5.8 million of whom were newly infected during 1997. At the 10th International Conference on AIDS and Sexually Transmitted Diseases in Africa, the President and Secretary of Health of France called upon developed countries to establish a Therapeutic Assistance Fund to make antiretrovirals available to people with HIV/AIDS in sub-Saharan Africa. While the annual per capita health budget in most African countries is less than US$10, triple antiretroviral therapy against AIDS in the developed world costs $12,000-14,000 per patient per year. Calculations based upon a lower per patient cost of $7000, and treating all 1.4 million African AIDS cases, would cost US$10 billion per year for drugs alone, more than 30 times the amount currently spent annually by international donors for AIDS programs in the entire developing world. Basic infrastructural requirements would have to be met were antiretrovirals made widely available, ranging from HIV screening and counseling to the provision of clean water with which to consume the required 20-30 tablets per day. High program costs will challenge long-term sustainability. Universal access to care and treatment for HIV infection and AIDS is not a reality in the developed world, let alone feasible in developing countries. Given the competing health care priorities in developing countries, the high costs of antiretroviral agents, poor infrastructure, and inability to sustain such a program, the French initiative is ill-advised and foolish public health practice.

  19. World Ocean Circulation Experiment

    Science.gov (United States)

    Clarke, R. Allyn

    1992-01-01

    The oceans are an equal partner with the atmosphere in the global climate system. The World Ocean Circulation Experiment is presently being implemented to improve ocean models that are useful for climate prediction both by encouraging more model development but more importantly by providing quality data sets that can be used to force or to validate such models. WOCE is the first oceanographic experiment that plans to generate and to use multiparameter global ocean data sets. In order for WOCE to succeed, oceanographers must establish and learn to use more effective methods of assembling, quality controlling, manipulating and distributing oceanographic data.

  20. Naturally Connecting the World

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ During China International Trade Fair for Home Textiles and Accessories held in Shanghai 2010(on Aug.25th the second day of the fair),Cotton Council International(CCI)hosted an exchange meeting targeted the COTTON USATM home textile licenses,taking"Naturally Connecting the World-Opportunities for Sourcing and Collaboration with Cotton-Made Home Textiles"as the theme of the meeting.CCI's representative institution in China invited the domestic famous home textile brands,enterprises and their customers to participate in the exchange which aims to introduce the current development trend of the global cotton textile industry through CCI,the powerful platform of communication.

  1. Key World Energy Statistics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The IEA produced its first handy, pocket-sized summary of key energy data in 1997. This new edition responds to the enormously positive reaction to the book since then. Key World Energy Statistics produced by the IEA contains timely, clearly-presented data on supply, transformation and consumption of all major energy sources. The interested businessman, journalist or student will have at his or her fingertips the annual Canadian production of coal, the electricity consumption in Thailand, the price of diesel oil in Spain and thousands of other useful energy facts. It exists in different formats to suit our readers' requirements.

  2. Dancing With the World

    Institute of Scientific and Technical Information of China (English)

    JIANG WANDI

    2010-01-01

    @@ Ballet, the dance created for court performances in Renaissance Europe that reached into the world of high art in early 17th century France, has long been loved by Chinese. As early as the 1920s, and into the 1950s and 1960s when the country was alienated from the West and its people were mired in poverty, some urban Chinese parents sent their daughters to ballet class after school, believing that this Western genre of art was the epitome of beauty and an educa-tional requirement for young ladies who held great expectations.

  3. World Technology Usage Lags

    OpenAIRE

    Diego A. Comin; Bart Hobijn; Emilie Rovito

    2006-01-01

    We present evidence on the differences in the intensity with which ten major technologies are used in 185 countries across the world. We do so by calculating how many years ago these technologies were used in the U.S. at the same intensity as they are used in the countries in our sample. We denote these time lags as technology usage lags and compare them with lags in real GDP per capita. We find that (i) technology usage lags are large, often comparable to lags in real GDP per capita, (ii) us...

  4. Black Brane World Scenarios

    CERN Document Server

    Moon, S H

    2001-01-01

    We consider a brane world residing in the interior region inside the horizon of extreme black branes. In this picture, the size of the horizon can be interpreted as the compactification size. The large mass hierarchy is simply translated into the large horizon size, which is provided by the magnitude of charges carried by the black branes. Hence, the macroscopic compactification size is a quantity calculable from the microscopic theory which has only one physical scale, and its stabilization is guaranteed from the charge conservation.

  5. Magic and Magical Worlds

    DEFF Research Database (Denmark)

    Børch, Marianne

    2013-01-01

    The article argues that where as Harry POtter lacks the " sense of the numinous" found in Tolkien and Pratchett, it has a special magic that plays upon the fantastic potential of language. Everyday language is full of metaphors, personifications, and strata of archaic beliefs; it has diversified...... discourse types (the use of Latin; technical terminology; class characteristics); and carries a great deal of associative cultural goods. Rowling is an expert in exploiting this - truly maical - aspect of human experience and thus shows how, merely in virtue of words, we all move in a magical world....

  6. World helicopter market study

    Science.gov (United States)

    Cleary, B.; Pearson, R. W.; Greenwood, S. W.; Kaplan, L.

    1978-01-01

    The extent of the threat to the US helicopter industry posed by a determined effort by foreign manufacturers, European companies in particular, to supply their own domestic markets and also to penetrate export markets, including the USA is assessed. Available data on US and world markets for civil and military uses are collated and presented in both graphic and tabular form showing the past history of production and markets and, where forecasts are available, anticipated future trends. The data are discussed on an item-by-item basis and inferences are drawn in as much depth as appears justified.

  7. World Cup television

    OpenAIRE

    2012-01-01

    In the last year of the first decade of the 21st century, in the verge of breaking into the era of digital television, it is important to know what kind of television model is available in Portugal. The analysis of the news coverage of the FIFA 2010 World Cup will certainly help in finding the answers. In this article, we present a study that centers its focus on news formats related to this great media event, broadcasted in both generalist as well as cable news networks between the 11th of J...

  8. The World of Comets

    Science.gov (United States)

    Guillemin, Amédée; Glaisher, James

    2010-10-01

    1. Beliefs and superstitions relative to comets; 2. Cometary astronomy up to the time of Newton; 3. The motions and orbits of comets; 4. Periodical comets; 5. Periodical comets; 6. The world of comets and cometary systems; 7. Physical and chemical constitution of comets; 8. Physical transformations of comets; 9. Mass and density of comets; 10. The light of comets; 11. Theory of cometary phenomena; 12. Comets and shooting stars; 13. Comets and the earth; 14. Physical influences of comets; 15. Some questions about comets; Tables.

  9. World Governments Focus

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    HEALTH was once a matter only doctors were concerned about. But in recent years, women’s health issues have been a part of the women’s movement. A woman’s right to health and health care is now the concern of society. In the 1990s, it is becoming apparent that quality of life is of foremost importance. At the World Summit for Children held in September 1990 in New York, government leaders from over 140 countries gathered for the first time to

  10. Belief in a Just World

    Directory of Open Access Journals (Sweden)

    Sibel Kilinc

    2011-01-01

    Full Text Available Belief in a just world hypothesis is defined as the belief that the world is a just place where people generally get what they deserve. It states that individuals have a need to believe that they live in a just world; they believe in a world where people get what they deserve and where people deserve what they get. Individuals believe that who work hard or who perform good acts obtain rewards for their actions, while the sinners and the laggards receive punishments instead. Similarly, individuals want to believe that positive outcomes, whether money, success, or happiness, are obtained only by good people and, conversely, that negative outcomes only happen to bad persons. Justice beliefs have been hypothesized as adaptive for dealing with day-to-day stres. Just world beliefs protect individuals from the daily negative psychological consequences of living in what is realistically an unjust world. In addition, just world beliefs are thought to enhance feelings of security to the extent that if the individual satisfies the conditions for being "good," he or she is protected from injustice. The belief in a just world, like other positive illusions, should contribute to the maintenance of one's mental health. Belief in a just world's is discussed in two ways: personal belief in a just world's answers the question “how much justly is the world to me?”, whereas the belief in a just world's in general answers the question “how much justly is the world?”

  11. World Area Forecast System (WAFS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The World Area Forecast System (WAFS) is a worldwide system by which world area forecast centers provide aeronautical meteorological en-route forecasts in uniform...

  12. Approaching the nano world

    Science.gov (United States)

    Stemmer, Andreas; Jacobs, Heiko; Knapp, Helmut F.

    1996-12-01

    At the interface of micro and macro world, vision plays a fundamental role in localizing targets and positioning micro- or nanorobots relative to them. Traditionally, far- field optics are used to achieve this task. However, in most practical applications optical diffraction limits resolution to the micrometer-range although image processing may provide us relative accuracies on the order of several nanometers in a few special cases. At ambient pressure, capillary condensation of water vapor severely hampers reproducible and reversible manipulations of micrometer- sized or smaller objects since the resulting adhesive forces between tool and object easily exceed the object's weight. The size of objects also dictates the useful dimensions of sensors and actuators and generally necessitates integration of several sensing and/or actuation functions into a single device. To overcome above mentioned difficulties in accessing the micro and nano world, sensing and actuating principles derived from scanning probe microscopies such as atomic force or optical near-field provide us with the necessary extension of the capabilities offered by traditional far-field systems. A fluid environment also prevents those hard-to-control effects of capillary forces.

  13. World Biofuels Study

    Energy Technology Data Exchange (ETDEWEB)

    Alfstad,T.

    2008-10-01

    This report forms part of a project entitled 'World Biofuels Study'. The objective is to study world biofuel markets and to examine the possible contribution that biofuel imports could make to help meet the Renewable Fuel Standard (RFS) of the Energy Independence and Security Act of 2007 (EISA). The study was sponsored by the Biomass Program of the Assistant Secretary for Energy Efficiency and Renewable Energy (EERE), U.S. Department of Energy. It is a collaborative effort among the Office of Policy and International Affairs (PI), Department of Energy and Oak Ridge National Laboratory (ORNL), National Renewable Energy Laboratory (NREL) and Brookhaven National Laboratory (BNL). The project consisted of three main components: (1) Assessment of the resource potential for biofuel feedstocks such as sugarcane, grains, soybean, palm oil and lignocellulosic crops and development of supply curves (ORNL). (2) Assessment of the cost and performance of biofuel production technologies (NREL). (3) Scenario-based analysis of world biofuel markets using the ETP global energy model with data developed in the first parts of the study (BNL). This report covers the modeling and analysis part of the project conducted by BNL in cooperation with PI. The Energy Technology Perspectives (ETP) energy system model was used as the analytical tool for this study. ETP is a 15 region global model designed using the MARKAL framework. MARKAL-based models are partial equilibrium models that incorporate a description of the physical energy system and provide a bottom-up approach to study the entire energy system. ETP was updated for this study with biomass resource data and biofuel production technology cost and performance data developed by ORNL and NREL under Tasks 1 and 2 of this project. Many countries around the world are embarking on ambitious biofuel policies through renewable fuel standards and economic incentives. As a result, the global biofuel demand is expected to grow very

  14. Becoming Citizens of the World

    Science.gov (United States)

    Stewart, Vivien

    2007-01-01

    The globalization of economies, the digitization of work, pressing health and security issues, and changing demographics have dramatically changed our world. Unlike previous generations, U.S. high school graduates will routinely buy from the world, sell to the world, work for international companies, manage employees from other cultures and…

  15. Diving into Real World Challenges

    Science.gov (United States)

    Saldana, Matt; Rodden, Leslie

    2012-01-01

    In this article, the authors discuss how educators can engage students in real world learning using their academic knowledge and technical skills. They describe how school districts have discovered that the world of robotics can help students use technical skills to solve simulated problems found in the real world, while understanding the…

  16. New Wonders of the World

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    New Seven Wonders of the World is a contemporary attempt to create analternative to historical lists of the Seven Wonders of the World.The result of a worldwide popularity poll was organized by the private,non-profit New Open World Corporation(NOWC).Its final list was announced on

  17. World Energy Outlook 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-11-07

    The 2008 report provides invaluable analysis to help policy makers around the world assess and address the challenges posed by worsening oil supply prospects, higher energy prices and rising emissions of greenhouse gases. In the WEO-2008 Reference Scenario, which assumes no new government policies, world primary energy demand grows by 1.6% per year on average between 2006 and 2030 - an increase of 45%. This is slower than projected last year, mainly due to the impact of the economic slowdown, prospects for higher energy prices and some new policy initiatives. Demand for oil rises from 85 million barrels per day now to 106 mb/d in 2030 - 10 mb/d less than projected last year. Demand for coal rises more than any other fuel in absolute terms, accounting for over a third of the increase in energy use. Modern renewables grow most rapidly, overtaking gas to become the second-largest source of electricity soon after 2010. China and India account for over half of incremental energy demand to 2030 while the Middle East emerges as a major new demand centre. The share of the world's energy consumed in cities grows from two-thirds to almost three-quarters in 2030. Almost all of the increase in fossil-energy production occurs in non-OECD countries. These trends call for energy-supply investment of $26.3 trillion to 2030, or over 1 trillion US dollars/year. Yet the credit squeeze could delay spending, potentially setting up a supply-crunch that could choke economic recovery. In addition to providing a comprehensive update of long-term energy projections to 2030, WEO-2008 takes a detailed look at the prospects for oil and gas production. Oil will remain the world's main source of energy for many years to come, even under the most optimistic of assumptions about the development of alternative technology. But the sources of oil, the cost of producing it and the prices that consumers will have to pay for it are extremely uncertain. It is far from certain that companies

  18. Confronting world hunger.

    Science.gov (United States)

    Huddleston, B

    1983-01-01

    In 1980, per capita food supplies were less than adequate in 53 developing countries. More than half of these were the predominantly rural, low income countries of South Asia, China, and Sub-Saharan Africa. Finding the proper balance between satisfying immediate human needs and building political and economic systems in which individuals can in the future acquire the means to satisfy their own requirements is the central issue facing those in the fight against world hunger. At the international level, developed countries have responded to world hunger by raising the minimum level of food aid provided when supplies are scarce and by creating a financing facility for cereal imports. The food and agriculture sector is receiving a highe priority than before in the allocation of international development assistance, and more attention is being given to the effects of both general food subsidies and targeted nutrition programs on future agricultural output. At the national level, over 40 developing countries have requested assistance from the World Food Council for the preparation of food sector strategies. Although such measures are important, they do not directly address local problems and individual needs. For example, dietary intake tends to be lower in urban than in rural households in Latin America at the same level of income. These urban groups require health and nutrition interventions that simultaneously address their immediate need for food, clean water, and health care and their more longterm need for employment. Longterm economic development that provides adequate income to all segments of the population is the best means to combat hunger, and income security also reduces incentives for large family size. The contribution of the international community should remain the transfer of resources and the provision of technical assistance. At the individual level, the need for targeted food distribution programs continues. Greater benefit can be obtained from

  19. A Creepy World

    CERN Document Server

    Sornette, Didier

    2014-01-01

    Using the mechanics of creep in material sciences as a metaphor, we present a general framework to understand the evolution of financial, economic and social systems and to construct scenarios for the future. In a nutshell, highly non-linear out-of-equilibrium systems subjected to exogenous perturbations tend to exhibit a long phase of slow apparent stable evolution, which are nothing but slow maturations towards instabilities, failures and changes of regimes. With examples from history where a small event had a cataclysmic consequence, we propose a novel view of the current state of the world via the logical scenarios that derive, avoiding the traps of an illusionary stability and simple linear extrapolation. The endogenous scenarios are "muddling along", "managing through" and "blood red abyss". The exogenous scenarios are "painful adjustment" and "golden east".

  20. Real-world outcomes

    DEFF Research Database (Denmark)

    2012-01-01

    analyses during one specific meeting. An important element of the latter is to assess whether the discussion of our results gives rise to respondents’ reflection, resistance, acceptance, rejection, or indifference, and whether this leads to changes in respondents’ views on culture and organizational......When working with discourse-based research in professional settings, one question invariably arises: How do we, as researchers, ensure that our findings are taken up by the professionals with whom analyses are carried out, leading to change in their social practices? The answer is that quite often...... of research findings may take place to ensure the creation of real-world outcomes for practitioners. The discussion will be centered around the interview study of the discursive constructions of culture in a Danish cross-border company and the possible implications of this for organizational collaboration...

  1. WORLD OF INNOVATION

    CERN Document Server

    Nikodem, Jan; Innovative Technologies in Management and Science

    2015-01-01

    This carefully edited book presents recent research in Innovative Technologies in Management and Science, representing a widely spread interdisciplinary research area with many applications in various disciplines including engineering, medicine, technology, or environment, among others. It consists of eleven invited and scholarly edited chapters written by respectable researchers and experts in the fields that integrate ideas and novel concepts in Intelligent Systems and Informatics. Most of the chapters were selected from the initial contributions to the World of Innovation Conference held on April 3, 2012 in Wroclaw, Poland. The contributions are focusing on research and development of the latest IT technologies, in the field of Cloud Computing, IT modeling, as well as optimization problems. The chapters presented can be grouped into three categories: Innovation supported by Clouds Technology, Innovation proposals in management area, and Theoretical refinement for innovative solutions.  

  2. The World Stress Map

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Knowledge of the stress field in the Earth's crust is a key issue for the understanding of geodynamic processes,seismic hazard assessment, and stability of underground openings such as waste disposals, tunnels, mines or wells, and reservoir management. The World Stress Map project is a collaborative project of academia,industry and governmental organizations that aims to understand the states and sources of tectonic stresses in the Earth's crust. We present the Worm Stress Map at 1:46,000,000 scale as a result of more than two decades of international collaboration. The map reveals that the first-order pattern of stress is of plate-wide scale, indicating that plate boundary forces are the major control of the stress orientations and the tectonic regime.

  3. World nuclear outlook 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-29

    As part of the EIA program to provide energy information, this analysis report presents the current status and projections through 2015 of nuclear capacity, generation, and fuel cycle requirements for all countries in the world using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the uranium market. Long-term projections of US nuclear capacity, generation, and spent fuel discharges for two different scenarios through 2040 are developed for the Department of Energy`s Office of Civilian Radioactive Waste Management (OCRWM). In turn, the OCRWM provides partial funding for preparation of this report. The projections of uranium requirements are provided to the Organization for Economic Cooperation and Development (OECD) for preparation of the Nuclear Energy Agency/OECD report, Summary of Nuclear Power and Fuel Cycle Data in OECD Member Countries.

  4. World energy outlook 2014

    CERN Document Server

    International Energy Agency. Paris

    2014-01-01

    The global energy landscape is evolving at a rapid pace, reshaping long-held expectations for our energy future. The 2014 edition of the World Energy Outlook (WEO) will incorporate all the latest data and developments to produce a comprehensive and authoritative analysis of medium- and longer-term energy trends. It will complement a full set of energy projections – which extend from today through, for the first time, the year 2040 – with strategic insights into their meaning for energy security, the economy and the environment. Oil, natural gas, coal, renewables and energy efficiency will be covered, along with updates on trends in energy-related CO2 emissions, fossil-fuel and renewable energy subsidies, and universal access to modern energy services.

  5. Landscape as World Picture

    DEFF Research Database (Denmark)

    Wamberg, Jacob

    Age, among the powers-that-be. The topic of Volume II is the breakthrough of the modern landscape image and its new perspectival vistas, transient time and cultivated - or completely deserted - terrains. This post-medieval paradigm shift is construed as the mature stage in the evolution of self......-consciousness, with an urban individual contemplating nature at an aesthetic distance. Apart from being structurally equivalent with the new Copernican cosmos and the colonial expansion of Western culture, the new territorial landscape image is shown to develop in close interaction with the early modern work ethic...... from Palaeolithic cave paintings through to 19th-century modernity. A structuralist comparison between this pattern and three additional fields of analysis - self-consciousness, socially-determined perception of nature, and world picture - reveals a fascinating insight into culture's macrohistorical...

  6. Landscape as World Picture

    DEFF Research Database (Denmark)

    Wamberg, Jacob

    -consciousness, with an urban individual contemplating nature at an aesthetic distance. Apart from being structurally equivalent with the new Copernican cosmos and the colonial expansion of Western culture, the new territorial landscape image is shown to develop in close interaction with the early modern work ethic......This book presents a new and comprehensive theory concerning the manner in which landscapes in Western pictorial art may be interpreted in relation to the cultures that created them. Its point of departure is a hitherto unexplored developmental pattern that characterises landscape representation...... from Palaeolithic cave paintings through to 19th-century modernity. A structuralist comparison between this pattern and three additional fields of analysis - self-consciousness, socially-determined perception of nature, and world picture - reveals a fascinating insight into culture's macrohistorical...

  7. World nuclear outlook 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-01

    As part of the EIA program to provide energy information, this analysis report presents the current status and projections through 2010 of nuclear capacity, generation, and fuel cycle requirements for all countries in the world using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the uranium market. Long-term projections of US nuclear capacity, generation, and spent fuel discharges for three different scenarios through 2040 are developed for the Department of Energy`s Office of Civilian Radioactive Waste Management (OCRWM). In turn, the OCRWM provides partial funding for preparation of this report. The projections of uranium requirements are provided to the Organization for Economic Cooperation and Development (OECD) for preparation of the Nuclear Energy Agency/OECD report, Summary of Nuclear Power and Fuel Cycle Data in OECD Member Countries.

  8. Jupiter's Water Worlds

    Science.gov (United States)

    Pappalardo, R. T.

    2004-01-01

    When the twin Voyager spacecraft cruised past Jupiter in 1979, they did more than rewrite the textbooks on the giant planet. Their cameras also unveiled the astounding diversity of the four planet-size moons of ice and stone known as the Galilean satellites. The Voyagers revealed the cratered countenance of Callisto, the valleys and ridges of Ganymede, the cracked face of Europa, and the spewing volcanoes of Io. But it would take a spacecraft named for Italian scientist Galileo, who discovered the moons in 1610, to reveal the true complexity of these worlds and to begin to divulge their interior secrets. Incredibly, the Galileo data strongly suggest that Jupiter's three large icy moons (all but rocky Io) hide interior oceans.

  9. World Energy Outlook 2010

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-11-09

    The world appears to be emerging from the worst economic crisis in decades. Many countries have made pledges under the Copenhagen Accord to reduce greenhouse-gas emissions. Commitments have also been made by the G-20 and APEC to phase out inefficient fossil-fuel subsidies. Are we, at last, on the path to a secure, reliable and environmentally sustainable energy system? Updated projections of energy demand, production, trade and investment, fuel by fuel and region by region to 2035 are provided in the 2010 edition of the World Energy Outlook (WEO). It includes, for the first time, a new scenario that anticipates future actions by governments to meet the commitments they have made to tackle climate change and growing energy insecurity. WEO-2010 shows: what more must be done and spent to achieve the goal of the Copenhagen Accord to limit the global temperature increase to 2 deg. C and how these actions would impact on oil markets; how emerging economies -- led by China and India -- will increasingly shape the global energy landscape; what role renewables can play in a clean and secure energy future; what removing fossil-fuel subsidies would mean for energy markets, climate change and state budgets; the trends in Caspian energy markets and the implications for global energy supply; the prospects for unconventional oil; and how to give the entire global population access to modern energy services. With extensive data, projections and analysis, this publication provides invaluable insights into how the energy system could evolve over the next quarter of a century. The book is essential reading for anyone with a stake in the energy sector.

  10. Other Worlds, Other Earths

    Science.gov (United States)

    Sunbury, Susan; Gould, R. R.

    2011-05-01

    The Harvard-Smithsonian Center for Astrophysics is developing a two-to-three week NSF-funded program for middle and high school students using telescope-based investigations of real world cutting edge scientific questions. The goal is to reveal and enhance students' understanding of core concepts in the physical sciences as well as to develop their proficiency in the practice of scientific inquiry. Specifically, students and teachers are joining scientists in the search for habitable worlds by exploring transiting exoplanets. Using robotic telescopes, image processing software and simulations, students take images and then measure the brightness of their target star to create a portrait of a transiting planet including how large it is; the tilt of its orbit; how far it is from its star and what its environment might be like. Once classes collect and analyze their own data, they can begin to compare, combine, and communicate their findings with others in the community. Interactive models help students predict what they might expect to find and interpret what they do find. During the past two years, the Center for Astrophysics has tested the concept in fifty middle-and high-school classrooms, enrichment classes and after school science clubs in 13 states across the United States. To date, astronomy, earth science, and physics students have successfully detected Jupiter-sized planets transiting stars such as TRES-3, HATP-10, and HATP-12. Preliminary results indicate that learning of core concept did occur. Gains in content were most significant in middle school students as this project delivered new information to them while it served primarily as a review of concepts and application of skills for advanced placement classes. A significant change also occurred in students’ self reported knowledge of exoplanets. There was also an increase in students’ awareness of exoplanets and attitudes about science after participating in this project.

  11. Ocean worlds exploration

    Science.gov (United States)

    Lunine, Jonathan I.

    2017-02-01

    Ocean worlds is the label given to objects in the solar system that host stable, globe-girdling bodies of liquid water-"oceans". Of these, the Earth is the only one to support its oceans on the surface, making it a model for habitable planets around other stars but not for habitable worlds elsewhere in the solar system. Elsewhere in the solar system, three objects-Jupiter's moon Europa, and Saturn's moons Enceladus and Titan-have subsurface oceans whose existence has been detected or inferred by two independent spacecraft techniques. A host of other bodies in the outer solar system are inferred by a single type of observation or by theoretical modeling to have subsurface oceans. This paper focusses on the three best-documented water oceans beyond Earth: those within Europa, Titan and Enceladus. Of these, Europa's is closest to the surface (less than 10 km and possibly less than 1 km in places), and hence potentially best suited for eventual direct exploration. Enceladus' ocean is deeper-5-40 km below its surface-but fractures beneath the south pole of this moon allow ice and gas from the ocean to escape to space where it has been sampled by mass spectrometers aboard the Cassini Saturn Orbiter. Titan's ocean is the deepest-perhaps 50-100 km-and no evidence for plumes or ice volcanism exist on the surface. In terms of the search for evidence of life within these oceans, the plume of ice and gas emanating from Enceladus makes this the moon of choice for a fast-track program to search for life. If plumes exist on Europa-yet to be confirmed-or places can be located where ocean water is extruded onto the surface, then the search for life on this lunar-sized body can also be accomplished quickly by the standards of outer solar system exploration.

  12. Reciprocity, World Prices and Welfare

    DEFF Research Database (Denmark)

    Raimondos-Møller, Pascalis; Woodland, Alan D.

    We examine in detail the circumstances under which reciprocity, as defined in Bagwell and Staiger (1999), leads to fixed world prices. We show that a change of tariffs satisfying reciprocity does not necessarily imply constant world prices in a world of many goods and countries. While...... it is possible to find tariff reforms that are consistent with both reciprocity and constant world prices, these reforms do not follow from the reciprocity condition, but rather from the requirement of unchanged world prices. We propose an alternative reciprocity rule that is guaranteed to raise the welfare...

  13. Learning from the World and Learning for the World: An Essay on World Schools

    Science.gov (United States)

    McKenzie, Malcolm

    2012-01-01

    This essay draws on the author's personal experiences as a head of school on three continents, over 20 years, as well as on some of his recent writings and talks. From Martin Luther King Jr's idea of a world house is derived the concept of a "world school". This project charts a way for national schools to develop world-minded graduates. It is…

  14. IMMANUEL WALLERSTEIN'S WORLD SYSTEM THEORY

    Directory of Open Access Journals (Sweden)

    Cosma Sorinel

    2010-12-01

    Full Text Available World-systems analysis is not a theory, but an approach to social analysis and social change developed, among others by the Immanuel Wallerstein. Professor Wallerstein writes in three domains of world-systems analysis: the historical development of the modern world-system; the contemporary crisis of the capitalist world-economy; the structures of knowledge. The American anlyst rejects the notion of a "Third World", claiming there is only one world connected by a complex network of economic exchange relationship. Our world system is characterized by mechanisms which bring about a redistribution of resources from the periphery to the core. His analytical approach has made a significant impact and established an institutional base devoted to the general approach.

  15. Regular Small-World Network

    Institute of Scientific and Technical Information of China (English)

    ZOU Zhi-Yun; MAO Bao-Hua; HAO Hai-Ming; GAO Jian-Zhi; YANG Jie-Jiao

    2009-01-01

    According to the deficiencies in Watts and Strogatz's small-world network model, we present a new regular model to establish the small-world network. Besides the property of the small-world, this model has other properties such as accuracy in controlling the average shortest path length L, and the average clustering coefficient C, also regular network topology as well as enhanced network robustness. This method improves the construction of the small-world network essentially, so that the regular small-world network closely resembles the actual network. We also present studies on the relationships among the quantities of a variety of edges, L and C in regular small-world network in detail. This research lays the foundation for the establishment of the regular small-world network and acts as a good guidance for further research of this model and its applications.

  16. 75 FR 49525 - World Color (USA), LLC Formerly Known as Quebecor World World Color Covington Including On-Site...

    Science.gov (United States)

    2010-08-13

    ... Employment and Training Administration World Color (USA), LLC Formerly Known as Quebecor World World Color... to workers of World Color (USA), LLC, formerly known as Quebecor World, World Color Covington... IH Services were employed on-site at the Covington, Tennessee, location of World Color (USA),...

  17. World news; Actualite international

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2005-06-01

    The 21. of April 2005, was held in Paris the 6. international petroleum meeting whose main theme was: the supply and demand. The participants of this summit have in majority argued for a greater opening of the productive countries to the international investments which are indispensable to face with a world demand of oil in full expansion. Total has announced the approval by the British authorities of the development of the gas and condensates deposit of north Forvie, located at about 440 km at the nord-east of Aberdeen. Technip and Kerr-McGee Oil and Gas Corp., have received the prestigious price of the Offshore Technology Conference 2005. The Norway and the United Kingdom have signed a cooperation treaty for stimulating the development of petroleum and natural gas deposits in North sea. The petroleum groups Royal Dutch Shell and ExxonMobil think to sale their shares in three fields in the North sea. Total and Lubrifin, one of the main manufacturers and distributors of lubricants and greases on the Romanian market, have just finalize an agreement for the establishment of a common firm: Total Lubrifin. The IEA has published a study for the governments to rapidly reduce the petroleum consumption in transports in the case of crisis or breakdown of the supply. In order to avoid an accident risk which could have disastrous environmental consequences, by the important transit in the Bosphore pass, a plan (dating from 1995) provides that the petroleum of the Caspian sea transiting by the Russian harbour of Novorossiisk, on North sea, be conveyed by sea way to the Bulgarian harbour of Bourgas, to be transported by pipeline on 320 km to the Alexandroupolis harbour. Vladimir Poutine has received last April to the Kremlin John Browne, general director of the British firm BP, came ask for its investment in Russia in the common firm: TNK-BP. The Algerian petroleum firm Sonatrach is in the 12. world place among the hundred first petroleum firms in the world. Shell Ivory Coast

  18. A world in balance.

    Science.gov (United States)

    Westing, A H

    1981-01-01

    The objectives of this paper are to define the scope of global population growth within the uncompromising everyday realities of technology, economies, and politics and to demonstrate the intimate between the human population problem and the increasing problem of Nature's destruction. It is hoped that the human species will come to its sense in time to create an adequate standard of living of all of its members in peace and environmental balance. The number of people the world can support is considered in terms of 1) the provision for a standard of living adequate for everyone's health and wellbeing, 2) consideration for wildlife and nature, and 3) reliance on existing levels of technology and politics. Standards of living are suggested for the affluent and the austere. The focus on the discussion is on standards of living, global carrying capacity, the imperatives of population control and respect for nature, humans versus wildlife, and the need for a universal declaration of respect for nature. Carrying capacity is determined by total land area, cultivated land area, forest land area, cereals (grain), and wood. Use per capita of each of the 5 essentials is determined for the affluent or austere standard of living. An affluent standard means that world population would be limited to 2 billion, which is 50% of the current population. An austere standard of living means a limit of 3 billion, or 33% less than the existing population. The unfortunate reality is that today's total population of 4.5 billion is increasing at an annual rate of 1.9% and is not expected to level off until it has increased 3 times. This population growth occurs at the expense of wildlife. Of the total terrestrial animal biomass, humans constitute 4% and domestic livestock 15%, which, in 40 years, will reach a combined 40% and lead to more species extinction. One species of bird or mammal will become extinct for each increase of 220 million people, which happens every 3 years. The solution is

  19. WORLD HEALTH DAY THEMES

    Directory of Open Access Journals (Sweden)

    S C Saxena

    2003-06-01

    Full Text Available 1970     - Early Detection of Cancer Saves Life.1971     - A Full Life Despite Diabetes.1972     - Your Heart is Your Health.1973     - Health Begins at Home.1974     - Better Food for a Healthier World.1975     - Small Pox - Point of no Return.1976     - Foresight Prevents Blindness.1977     - Immunise and Protect Your Child.1978     - Down With High Blood Pressure.1979     - A Health Child-A Sure Future.1980     - Smoking or Health - The Choice is Yours.1981     - Health for all for by the Year 2000.1982     - Add Years to Life.1983     - Health for all by 2000 - The Count Down has Begun1984     - Children’s Health: Tomorrows Wealth.1985     - Health Youth : Our best Resource.1986     - Health Living - Everyone a Winner.1987     - Immunisation - A Chance for Every Child.1988     - Health For All - All for Health.1989-Let’s Talk Health.1990    - Our Planet - Ourhealth; Think Globally, Act Locally.1991    - Should Disaster Strike - Be Prepared.1992    - Health Beat - The Rhythm of Life.1993    - Handle Life with Care - Prevent Violence and Negligence.1994    - Our Health for a Healthy Life.1995    - Target - 2000 - A World Without Polio.1996    - Healthy Cities for Better Life.1997    - Emerging Infectious Diseases.1998    - Safe Motherhood.1999    - Active Ageing Makes the Difference.2000     - Be a Life Saver, Be a Blood Doner; Blood Saves Life.2001     - Stop Exclusion, Dare to Care.2002     - Move for Health.- Shape the Future of Life, Healthy Environments for Children

  20. A WORLD BEYOND HUMAN

    Directory of Open Access Journals (Sweden)

    David Abram

    2013-12-01

    Full Text Available From an initial project to investigate the relationship between magic and traditional medicine as practiced by shamans in Southern rural Asia, the focus of attention gradually shifted to an awareness of the negotiation traditional medicine people or shamans exert between the human community and the larger community of beings. This attentiveness to a more-than-human world does not occur at a supernatural domain above nature or inside her personal self but is the result of the shaman’s special ability to project her consciousness horizontally to other forms of sensibility with which human existence is interwoven. The ecological function of the shaman is to maintain a constant balance between what is taken and what is given from the human community to the larger community. The spirits of indigenous cultures are not defined in opposition to materiality but are essentially those modes of intelligence or awareness that do not possess a human form. By exploring different landscapes, and the sensibility living in them, a new sensitivity is awoken that allows for communication with those intelligences. However, the drowning of these other voices in Western culture, which reduces otherness to an object, creates an uneasiness that is hardly perceived except as an inability to interact with anything more-than-human and its dire consequences in the form of “civilization’s” destructive behavior.

  1. Brane-World Multigravity

    CERN Document Server

    Papazoglou, A

    2001-01-01

    In this thesis, we discuss the idea of multigravity, namely the possibility that a significant component of gravity that we feel at intermediate distances (1 mm < r < 10^26 cm) is due to massive but ultralight gravitons. We demonstrate how this phenomenon can be realized in brane-world models in a spacetime with more than four dimensions and discuss how modifications of gravity at cosmological scales emerge as a consequence. Firstly, we consider five dimensional multigravity models with flat branes. We see how the existence of freely moving negative tension branes gives rise to ultralight graviton Kaluza-Klein states. Secondly, we study the moduli corresponding to the position of the branes and the size of the extra dimension, the radions and the dilaton respectively. We show that the radions corresponding to negative tension branes have wrong sign kinetic term. We also derive a stabilization condition for the dilaton in a brane model with general bulk scalar field dynamics. Thirdly, we show how we can ...

  2. World Energy Outlook 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Industry and government decision-makers and others with a stake in the energy sector all benefit from the contents of World Energy Outlook (WEO) 2012. It presents authoritative projections of energy trends through to 2035 and insights into what they mean for energy security, environmental sustainability and economic development. Oil, coal, natural gas, renewables and nuclear power are all covered, together with an update on climate change issues. Global energy demand, production, trade, investment and carbon dioxide emissions are broken down by region or country, by fuel and by sector. Special strategic analyses cover: What unlocking the purely economic potential for energy efficiency could do, country by country and sector by sector, for energy markets, the economy and the environment; The Iraqi energy sector, examining both its importance in satisfying the country’s own needs and its crucial role in meeting global oil and gas demand; The water-energy nexus, as water resources become increasingly stressed and access more contentious; Measures of progress towards providing universal access to modern energy services. There are many uncertainties, but many decisions cannot wait. The insights of this publication are invaluable to those who must shape our energy future.

  3. World Energy Outlook 2013

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    In a world where big differences in regional energy prices impact competitiveness, who are the potential winners and losers? Huge volumes of oil are needed to meet growing demand and offset declines in existing fields. Where will it all come from? What could trigger a rapid convergence in natural gas prices between Asia, Europe and North America, and how would it affect energy markets? Is the growth in renewable energy self-sustaining and is it sufficient to put us on track to meet global climate goals? How much progress is being made in phasing out fossil-fuel subsidies and expanding access to modern energy services to the world’s poor? The answers to these and many other questions are found in WEO-2013, which covers the prospects for all energy sources, regions and sectors to 2035. Oil is analysed in-depth: resources, production, demand, refining and international trade. Energy efficiency – a major factor in the global energy balance – is treated in much the same way as conventional fuels: Its prospects and contribution are presented in a dedicated chapter. And the report examines the outlook for Brazil's energy sector in detail and the implications for the global energy landscape.

  4. New Worlds Airship

    Science.gov (United States)

    Harness, Anthony; Cash, Webster; Shipley, Ann; Glassman, Tiffany; Warwick, Steve

    2013-09-01

    We review the progress on the New Worlds Airship project, which has the eventual goal of suborbitally mapping the Alpha Centauri planetary system into the Habitable Zone. This project consists of a telescope viewing a star that is occulted by a starshade suspended from an airship. The starshade suppresses the starlight such that fainter planetary objects near the star are revealed. A visual sensor is used to determine the position of the starshade and keep the telescope within the starshade's shadow. In the first attempt to demonstrate starshades through astronomical observations, we have built a precision line of sight position indicator and flew it on a Zeppelin in October (2012). Since the airship provider went out of business we have been redesigning the project to use Vertical Takeoff Vertical Landing rockets instead. These Suborbital Reusable Launch Vehicles will serve as a starshade platform and test bed for further development of the visual sensor. We have completed ground tests of starshades on dry lakebeds and have shown excellent contrast. We are now attempting to use starshades on hilltops to occult stars and perform high contrast imaging of outer planetary systems such as the debris disk around Fomalhaut.

  5. Impossible Worlds and Logical Omniscience

    DEFF Research Database (Denmark)

    Bjerring, Jens Christian Krarup

    2013-01-01

    the use of impossible worlds where the truths of logic can be false. As we shall see, if we admit impossible worlds where “anything goes” in modal space, it is easy to model extremely non-ideal agents that are incapable of performing even the most elementary logical deductions. A much harder...... falsehoods, they are nevertheless able to rule out blatantly impossible worlds that verify obvious logical falsehoods. To model moderately ideal agents, I argue, the job is to construct a modal space that contains only possible and non-trivially impossible worlds where it is not the case that “anything goes......In this paper, I investigate whether we can use a world-involving framework to model the epistemic states of non-ideal agents. The standard possible-world framework falters in this respect because of a commitment to logical omniscience. A familiar attempt to overcome this problem centers around...

  6. Security in the Third World

    OpenAIRE

    Özgediz, Gülden

    2004-01-01

    Ankara : The Department of International Relations, Bilkent Univ., 2004. Thesis (Master's) -- Bilkent University, 2004. Includes bibliographical references leaves 134-144. This thesis traces the development of thinking about security in the Third World from its Cold War past to its post-Cold War present. For this purpose, it examines three main approaches (traditional. Third World and critical) to the study of security in the Third World. It begins with a critical overview o...

  7. World Expo and Exhibition Industry

    Institute of Scientific and Technical Information of China (English)

    Guo Liqin

    2010-01-01

    @@ February 8 witnessed the construction of 2010 World Expo's China Pavilion completed after two years' work. The pavilion, in the shape of an oriental crown,showcases the spirit of traditional Chinese culture. It is significant since all other nation's pavilion constructed only for temporary exhibition, but China's Pavilion will be lasting architecture as the symbol of world civilization. Another similar famous case is Eiffel Tower which was built as the entrance of the world expo held in. 1889.

  8. Corporate Training in Virtual Worlds

    Directory of Open Access Journals (Sweden)

    Charles Nebolsky

    2004-12-01

    Full Text Available This paper presents virtual training worlds that are relatively low-cost distributed collaborative learning environments suitable for corporate training. A virtual training world allows a facilitator, experts and trainees communicating and acting in the virtual environment for practicing skills during collaborative problem solving. Using these environments is beneficial to both trainees and corporations. Two system prototypes – the sales training and the leadership training virtual worlds – are described. The leadership training course design is discussed in details.

  9. The future dynamic world model

    Science.gov (United States)

    Karr, Thomas J.

    2014-10-01

    Defense and security forces exploit sensor data by means of a model of the world. They use a world model to geolocate sensor data, fuse it with other data, navigate platforms, recognize features and feature changes, etc. However, their need for situational awareness today exceeds the capabilities of their current world model for defense operations, despite the great advances of sensing technology in recent decades. I review emerging technologies that may enable a great improvement in the spatial and spectral coverage, the timeliness, and the functional insight of their world model.

  10. Food and My World: My Health My World.

    Science.gov (United States)

    Tharp, Barbara; Dresden, Judith; Denk, James; Moreno, Nancy

    This curriculum guide for students in grades K-4 is part of the My Health My World Series. It explores environmental issues, focusing on food and the environment. The unit includes (1) an activities guide for teachers entitled, "Food and My World," which presents activity-based lessons that entice students to discover concepts in…

  11. Creating a Social World

    Science.gov (United States)

    Kendler, Kenneth S.; Jacobson, Kristen C.; Gardner, Charles O.; Gillespie, Nathan; Aggen, Steven A.; Prescott, Carol A.

    2014-01-01

    Context Peer-group deviance is strongly associated with externalizing behaviors. We have limited knowledge of the sources of individual differences in peer-group deviance. Objective To clarify genetic and environmental contributions to peer-group deviance in twins from mid-childhood through early adulthood. Design Retrospective assessments using a life-history calendar. Analysis by biometric growth curves. Setting General community. Participants Members of male-male pairs from the population-based Virginia Twin Registry personally interviewed in 1998–2004 (n=1802). Main Outcome Measure Self-reported peer-group deviance at ages 8 to 11, 12 to 14, 15 to 17, 18 to 21, and 22 to 25 years. Results Mean and variance of peer-group deviance increased substantially with age. Genetic effects on peer-group deviance showed a strong and steady increase over time. Family environment generally declined in importance over time. Individual-specific environmental influences on peer-group deviance levels were stable in the first 3 age periods and then increased as most twins left home. When standardized, the heritability of peer-group deviance is approximately 30% at ages 8 to 11 years and rises to approximately 50% across the last 3 time periods. Both genes and shared environment contributed to individual differences in the developmental trajectory of peer-group deviance. However, while the correlation between childhood peer-group deviance levels and the subsequent slope of peer-group deviance over time resulting from genetic factors was positive, the same relationship resulting from shared environmental factors was negative. Conclusions As male twins mature and create their own social worlds, genetic factors play an increasingly important role in their choice of peers, while shared environment becomes less influential. The individual specific environment increases in importance when individuals leave home. Individuals who have deviant peers in childhood, as a result of genetic vs

  12. The Origin of the World

    Institute of Scientific and Technical Information of China (English)

    李梦遥

    2010-01-01

    @@ The world came into being① thousands of years ago.For a long time,it grew,changed,and developed to be what we see it today.However,at the very beginning,how did our world emerge? Different cultures provide various explanations.

  13. Regular Numbers and Mathematical Worlds

    Science.gov (United States)

    Whitacre, Ian; Bouhjar, Khalid; Bishop, Jessica Pierson; Philipp, Randolph; Schappelle, Bonnie P.

    2016-01-01

    Rather than describing the challenges of integer learning in terms of a transition from positive to negative numbers, we have arrived at a different perspective: We view students as inhabiting distinct mathematical worlds consisting of particular types of numbers (as construed by the students). These worlds distinguish and illuminate students'…

  14. World's finest tech sites immortalised

    CERN Multimedia

    2008-01-01

    They may have transformed man's understanding of the universe but the monumental impact of the world's first large radio telescope and the planet's largest particle physics lab has never been fully recognised. Now both Jodrell Bank and CERN are among the technological landmarks that could be immortalised alongside the pyramids of Egypt and Taj Mahal on UNESCO's World Heritage Site (WHS) list.

  15. Alice in the Real World

    Science.gov (United States)

    Parker, Tom

    2012-01-01

    As a fifth-grade mathematics teacher, the author tries to create authentic problem-solving activities that connect to the world in which his students live. He discovered a natural connection to his students' real world at a computer camp. A friend introduced him to Alice, a computer application developed at Carnegie Mellon, under the leadership of…

  16. Making “World Machines”

    DEFF Research Database (Denmark)

    Light, Ann; Bardzell, Jeffrey; Bardzell, Shaowen;

    2015-01-01

    be combined and turned to crowd-sourcing public engagement with shared world issues - as an alternative to business-as-usual in the context of developing and deploying networked technology. We combine theoretical aspects of world machines, such as what a political entity of this kind might seek to do...

  17. Organising, Educating... Changing the World

    Science.gov (United States)

    Grayson, John

    2005-01-01

    Over the past few years a constellation of social movements and organisations concerned with issues of globalisation and world poverty have exploded onto the world stage. They have mobilised demonstrations, organised mass gatherings and conferences, created e-networks and websites and become major players in international political lobbying and…

  18. Ethnography in a Virtual World

    Science.gov (United States)

    Shumar, Wesley; Madison, Nora

    2013-01-01

    This article situates the discussion of virtual ethnography within the larger political/economic changes of twenty-first century consumer capitalism and suggests that increasingly our entire social world is a virtual world and that there were very particular utopian and dystopian framings of virtual community growing out of that history. The…

  19. Natural Dyes. Third World Science.

    Science.gov (United States)

    Jones, Natalie; Hughes, Wyn

    This unit, developed by the Third World Science Project, is designed to add a multicultural element to existing science syllabi (for students aged 11-16) in the United Kingdom. The project seeks to develop an appreciation of the: boundless fascination of the natural world; knowledge, skills, and expertise possessed by men/women everywhere;…

  20. World Reaction to Virtual Space

    Science.gov (United States)

    1999-01-01

    DRaW Computing developed virtual reality software for the International Space Station. Open Worlds, as the software has been named, can be made to support Java scripting and virtual reality hardware devices. Open Worlds permits the use of VRML script nodes to add virtual reality capabilities to the user's applications.

  1. Space exploration and world peace

    Science.gov (United States)

    Mercieca, C.

    1972-01-01

    The possibility of using space exploration as an instrument in procuring world peace is studied. Suggestions for obtaining such a peace, utilizing space programs, include removal of worldwide educational and communication barriers, building of an emotionally and socially stable society, creation of a unit or whole world rather than the mine and yours concept, and reevaluation and reorientation of human relations and values.

  2. Clay Pots. Third World Science.

    Science.gov (United States)

    Jones, Natalie; Hughes, Wyn

    This unit, developed by the Third World Science Project, is designed to add a multicultural element to existing science syllabi (for students aged 11-16) in the United Kingdom. The project seeks to develop an appreciation of the: boundless fascination of the natural world; knowledge, skills, and expertise possessed by men/women everywhere;…

  3. Our Brave New World Today

    Science.gov (United States)

    Stivers, Richard

    2010-01-01

    Aldous Huxley is perhaps the only author to have written a work of science fiction and a work of nonfiction to ascertain whether fiction had become reality. Both "Brave New World" and "Brave New World Revisited" are discussed and compared with Jacques Ellul's work on technology.

  4. Canada and the Third World.

    Science.gov (United States)

    Burghardt, Andrew F.

    1984-01-01

    Canada did not develop strong ties with the Third World until well after World War II. Three factors that have channeled and limited Canada's relationships with developing nations--location, history, and internal political relationships--are discussed. Also examined are patterns of Canadian foreign aid and investment and peace-seeking efforts. (RM)

  5. Methane Digestors. Third World Science.

    Science.gov (United States)

    Jones, Natalie; Hughes, Wyn

    This unit, developed by the Third World Science Project, is designed to add a multicultural element to existing science syllabi (for students aged 11-16) in the United Kingdom. The project seeks to develop an appreciation of the: boundless fascination of the natural world; knowledge, skills, and expertise possessed by men/women everywhere;…

  6. The World of Sports Medicine

    Science.gov (United States)

    Emeagwali, N. Susan

    2008-01-01

    Soon, the best athletes in the world will face each other at the Summer Olympics in Beijing. Many of them will sustain injuries, or seek to prevent them, and will be thankful that among their entourages are some of the best sports medicine professionals in the world. When an athlete collapses from fatigue, or something else, there will be a group…

  7. The metaphors of virtual worlds

    DEFF Research Database (Denmark)

    Reinhard, CarrieLynn D.

    The analysis of recollections of experiencing two types of virtual worlds where the recollections were in the form of metaphors.......The analysis of recollections of experiencing two types of virtual worlds where the recollections were in the form of metaphors....

  8. Worlds in the Everett Interpretation

    CERN Document Server

    Wallace, D

    2001-01-01

    This is a discussion of how we can understand the world-view given to us by the Everett interpretation of quantum mechanics, and in particular the role played by the concept of `world'. The view presented is that we are entitled to use `many-worlds' terminology even if the theory does not specify the worlds in the formalism; this is defended by means of an extensive analogy with the concept of an `instant' or moment of time in relativity, with the lack of a preferred foliation of spacetime being compared with the lack of a preferred basis in quantum theory. Implications for identity of worlds over time, and for relativistic quantum mechanics, are discussed.

  9. World Assessment Unit Geological Characterizations, 2000 World Petroleum Assessment

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapfile includes arcs and polygons that describe U.S. Geological Survey defined petroleum resource Assessment Units of the World. Each assessment unit is...

  10. Xinjiang Girl World Super Model

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Leading Chinese model Yue Mei won thetitle of World Super Model at the ’98 WorldSuper Model Competition held in FranceSeptember 6 - 17. Yue, a university studentfrom the Xinjiang Uygur AutonomousRegion, had won the top title at ’98 ChinaSuper Model Competition held in Beijingone month earier.After that, she underwentone month’s professional modeling trainingwith the New Silk Road ModelingManagement Company before setting off forthe world competition. In France, Yueimpressed the judges with her strikingfeatures, and display of oriental elegance and

  11. Women Swimmers Win World Recognition

    Institute of Scientific and Technical Information of China (English)

    JANE; SHAW

    1995-01-01

    THE Seventh World Webfoot Swimming Championships concluded with the women’s 4x100-meter relay event. Chinese swimmers took all 12 gold medals in the women’s events. China has taken part in four world championships and has won the team championship three times in eight years. Diving competitions began in 1959 in China. The Chinese Women’s Diving Team impressed audiences with its fighting spirit in rivers, lakes and the sea. But the "cultural revolution" discontinued the development of diving as well as many other sports. It was not until 1975 that diving was resumed. In 1984, Yu Jianling, from Hubei Province, broke two world records three times

  12. Rockets in World War I

    Science.gov (United States)

    2004-01-01

    World War I enlisted rockets once again for military purposes. French pilots rigged rockets to the wing struts of their airplanes and aimed them at enemy observation balloons filled with highly inflammable hydrogen.

  13. American Nurses Association Nursing World

    Science.gov (United States)

    ... ANA Staff Nurses Advanced Practice Nurses Nurse Managers Nursing Research Student Nurses Educators What is Nursing? NursingWorld About ... Online Course Alert! The Ins and Outs of Nursing Research 11/09/16 ANA Ready to Work with ...

  14. World Ocean Atlas 2005, Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  15. World Ocean Atlas 2005, Temperature

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  16. Tomorrow`s solar world

    Energy Technology Data Exchange (ETDEWEB)

    Leitch, Meg

    1996-12-31

    The largest privately funded solar power installation in the world is at the Florida Walt Disney World. It is the Universe of Energy exhibit at the Experimental Prototype Community of the World. The Universe of Energy shows the development and exploitation of energy sources and how energy is used and includes a recreation of the primeval world from which coal and oil deposits were formed. Visitors travel through two giant theatres in electrically powered cars. Most of the ride system is powered by a solar cell array on the roof of the building. The array is composed of 2,200 modules each made up of 36 cells and can generate 70kW of DC power which is fed through an inverter to convert it to AC. (UK)

  17. Big, Fat World of Lipids

    Science.gov (United States)

    ... Science Home Page The Big, Fat World of Lipids By Emily Carlson Posted August 9, 2012 Cholesterol ... ways to diagnose and treat lipid-related conditions. Lipid Encyclopedia Just as genomics and proteomics spurred advances ...

  18. World Ocean Atlas 2005, Salinity

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  19. World Ocean Atlas 2005, Salinity

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World Ocean Atlas 2005 (WOA05) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen...

  20. Quantum Small-world Networks

    CERN Document Server

    Wei, Zong-Wen; Han, Xiao-Pu

    2011-01-01

    Quantum networks are critical to quantum communication and distributed quantum computing. Here we propose a small-world model of large-scale quantum repeater networks, where "small-world" is a fundamental concept rooted in complex networks, which describe a broad range of real systems. The core of the model is to relate the hierarchical fashion of measurements to coarse-graining process, when quantum repeater protocols are implemented. We demonstrate that quantum repeater networks with fractal structure can be enlarged with certain length scale in geographic space, while preserving topology by performing renormalization. Actually, renormalization here serves as an organizing principle determining the distribution of long-range entangled links over quantum networks, which gives rise to fractal to small-world transition. Furthermore, by iterative implementation of renormalization on the former coarse-grained network, we eventually obtain an onion-like, hierarchical quantum small-world network, where the distanc...

  1. ENHANCING SPIRITUALISM IN VIRTUAL WORLD

    Directory of Open Access Journals (Sweden)

    Kiran Lata DANGWAL

    2012-04-01

    Full Text Available Spiritualism is one word which puts man on the highest plinth of life. Spirituality is the way we find meaning, hope, comfort and inner peace in life. Spirituality in the virtual World is generally known as Virtual Spirituality. A goldmine of wisdom from all kinds of religious and spiritual philosophies, traditions and practices can be found in virtual World now. Technology and Spirituality together forms the material to which man can incline on to and work for the development of a globe in which war will be considered a taboo and violence a rejected dogma. Therefore there is an urgent nee to made the world a safe place to live in and the spiritual reconstruction can help us in achieving this.Spiritualism, Virtual World, Online Technology.

  2. World of Forensic Laboratory Testing

    Science.gov (United States)

    ... Global Sites Search Help? The World of Forensic Laboratory Testing Share this page: Was this page helpful? ... made-for-television lab scenario, real-life forensic laboratories' analyses of evidence are much slower. For example, ...

  3. Woman Precision Parachuting World Champion

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    1. Twenty-four-year-old Sheng Jun won three gold medals at the 22nd World Parachuting Championships. one for women’s group total score title. one for women’s group precision landing title and the other for women’s individual precision landing title. She also created the women’s individual precision landing record of the World Championships by scoring 0.00 ten times.

  4. Language learning in virtual worlds

    OpenAIRE

    Saba, Riad

    2013-01-01

    Language Learning has utilized technology for decades, and while world-wide social dynamics place more demands for language learning, there has not been a widespread use of a specific technology as the dominant medium for language learning. In the meanwhile, Virtual Worlds technology emerged during the last two decades as an immersive technology that offers an online representation of reality, allowing user interaction with the surrounding environment including objects and other users through...

  5. Distributed Pervasive Worlds: The Case of Exergames

    Science.gov (United States)

    Laine, Teemu H.; Sedano, Carolina Islas

    2015-01-01

    Pervasive worlds are computing environments where a virtual world converges with the physical world through context-aware technologies such as sensors. In pervasive worlds, technology is distributed among entities that may be distributed geographically. We explore the concept, possibilities, and challenges of distributed pervasive worlds in a case…

  6. The Future of Virtual Worlds

    Science.gov (United States)

    Bainbridge, William Sims; Lutters, Wayne; Rhoten, Diana; Lowood, Henry

    This book, like the May 2008 conference in World of Warcraft, ends with projections toward what the future might hold for virtual worlds. Every chapter thus far has included speculations about future directions, even while standing on data from the past. This last chapter, like the final session of the conference on which it is based, incorporates comments from dozens of participants into a stream of ideas. We have edited selected comments together with the panel's contributions. Our intention is to provide a portal from this book into a wider virtual community comprising researchers and residents in virtual worlds. The discussion surveys many recent lines of development, some of which have already been surveyed in scientific and historical literature, or by journalists (Au 2008; Castronova 2007; Guest 2007; Ludlow and Wallace 2007). Yet, many of the topics here have not received such attention. Considered as a set of socio-technical innovations, virtual worlds are not just about technical possibilities; they also inspired the participants to consider the economic bases for investing in those possibilities and the novel cultural, social, and artistic forms virtual worlds might offer.

  7. Microenterprise in the First and Third Worlds

    OpenAIRE

    Mark Schreiner

    2001-01-01

    Sparked by examples from the third world, hundreds of microenterprise programmes have been started in the first world. Will they be successful? This paper reviews the evidence and concludes that microenterprise development is more difficult in the first world. For example, the microenterprise sector in the first world is smaller because most people can get wage jobs and because of the public safety net. Unlike third-world entrepreneurs, first-world entrepreneurs are more often constrained by ...

  8. Microenterprise in the First and Third Worlds

    OpenAIRE

    Mark Schreiner

    2001-01-01

    Sparked by examples from the third world, hundreds of microenterprise programmes have been started in the first world. Will they be successful? This paper reviews the evidence and concludes that microenterprise development is more difficult in the first world. For example, the microenterprise sector in the first world is smaller because most people can get wage jobs and because of the public safety net. Unlike third-world entrepreneurs, first-world entrepreneurs are more often constrained by ...

  9. Wikipedia ranking of world universities

    Science.gov (United States)

    Lages, José; Patt, Antoine; Shepelyansky, Dima L.

    2016-03-01

    We use the directed networks between articles of 24 Wikipedia language editions for producing the wikipedia ranking of world Universities (WRWU) using PageRank, 2DRank and CheiRank algorithms. This approach allows to incorporate various cultural views on world universities using the mathematical statistical analysis independent of cultural preferences. The Wikipedia ranking of top 100 universities provides about 60% overlap with the Shanghai university ranking demonstrating the reliable features of this approach. At the same time WRWU incorporates all knowledge accumulated at 24 Wikipedia editions giving stronger highlights for historically important universities leading to a different estimation of efficiency of world countries in university education. The historical development of university ranking is analyzed during ten centuries of their history.

  10. World-line perturbation theory

    CERN Document Server

    van Holten, Jan-Willem

    2016-01-01

    The motion of a compact body in space and time is commonly described by the world line of a point representing the instantaneous position of the body. In General Relativity such a world-line formalism is not quite straightforward because of the strict impossibility to accommodate point masses and rigid bodies. In many situations of practical interest it can still be made to work using an effective hamiltonian or energy-momentum tensor for a finite number of collective degrees of freedom of the compact object. Even so exact solutions of the equations of motion are often not available. In such cases families of world lines of compact bodies in curved space-times can be constructed by a perturbative procedure based on generalized geodesic deviation equations. Examples for simple test masses and for spinning test bodies are presented.

  11. Being in a Virtual World

    DEFF Research Database (Denmark)

    Walther-Hansen, Mads; Grimshaw, Mark

    2016-01-01

    We present a theoretical framework by which virtual world sound designers may work towards the attainment of presence. Drawing on the study of cognitive metaphors and the view that sound is an emergent perception we offer an account of the environment as a salient and dynamic construct that funct......We present a theoretical framework by which virtual world sound designers may work towards the attainment of presence. Drawing on the study of cognitive metaphors and the view that sound is an emergent perception we offer an account of the environment as a salient and dynamic construct...... that functions as a synecdoche for the nonself. Separating environment from world, we discuss the role of sound in the forming of the environment and argue that it is this environment that establishes the means for presence because it is the process behind the construction of the environment that individuates...

  12. SYMMETRY IN WORLD TRADE NETWORK

    Institute of Scientific and Technical Information of China (English)

    Hui WANG; Guangle YAN; Yanghua XIAO

    2009-01-01

    Symmetry of the world trade network provides a novel perspective to understand the world-wide trading system. However, symmetry in the world trade network (WTN) has been rarely studied so far. In this paper, the authors systematically explore the symmetry in WTN. The authors construct WTN in 2005 and explore the size and structure of its automorphism group, through which the authors find that WTN is symmetric, particularly, locally symmetric to a certain degree. Furthermore, the authors work out the symmetric motifs of WTN and investigate the structure and function of the symmetric motifs, coming to the conclusion that local symmetry will have great effect on the stability of the WTN and that continuous symmetry-breakings will generate complexity and diversity of the trade network. Finally, utilizing the local symmetry of the network, the authors work out the quotient of WTN, which is the structural skeleton dominating stability and evolution of WTN.

  13. Virtual Laboratories and Virtual Worlds

    CERN Document Server

    Hut, Piet

    2007-01-01

    Since we cannot put stars in a laboratory, astrophysicists had to wait till the invention of computers before becoming laboratory scientists. For half a century now, we have been conducting experiments in our virtual laboratories. However, we ourselves have remained behind the keyboard, with the screen of the monitor separating us from the world we are simulating. Recently, 3D on-line technology, developed first for games but now deployed in virtual worlds like Second Life, is beginning to make it possible for astrophysicists to enter their virtual labs themselves, in virtual form as avatars. This has several advantages, from new possibilities to explore the results of the simulations to a shared presence in a virtual lab with remote collaborators on different continents. I will report my experiences with the use of Qwaq Forums, a virtual world developed by a new company (see http://www.qwaq.com)

  14. World Health Organization encourages traditional medicine in the third world.

    Science.gov (United States)

    Ozorio, P

    1979-01-01

    The executive board of WHO (World Health Organization) recently passed a resolution calling on countries 1) to promote the role of traditional practitioners in the health care systems of developing countries and 2) to allocate more financial support for the development of traditional medical systems. The board also urged the medical profession not to undervalue the traditional medical system. WHO recognizes that modern medical care is unavailable to the majority of the world's poor residents and that traditional birth attendants deliver 2/3 of the world's babies. To fulfill the primary health needs of all the world's inhabitants it will be necessary to utilize both the Western and the traditional medical system. In some countries, such as Sri Lanka, India, and China the traditional health system is legally recognized. WHO also advocates utilizing those medicinal plants and remedies used by traditional practitioners to effectively treat their patients. Example of some of these plants are 1) Ammi visnage, a Mediterranean plant, used to treat angina pectoris; 2) Cymbopogan proximus, an Egyptian plant, used to remove urinary tract stones; 3) the root of Combretum, used in Ghana to treat guinea-worm; 4) bitter leaf, a Nigerian plant which kills mouth bacteria; and 5) Desmodium adcendens, Thonningia sanguinea, and Deinbollia pinnata used in various combinations to treat bronchial asthma.

  15. World Culture in the Capitalist World-System in Transition

    Science.gov (United States)

    Griffiths, Tom G.; Arnove, Robert F.

    2015-01-01

    World culture theory (WCT) offers an explanatory framework for macro-level comparative analyses of systems of mass education, including their structures, accompanying policies and their curricular and pedagogical practices. WCT has contributed to broader efforts to overcome methodological nationalism in comparative research. In this paper, we…

  16. World Culture in the Capitalist World-System in Transition

    Science.gov (United States)

    Griffiths, Tom G.; Arnove, Robert F.

    2015-01-01

    World culture theory (WCT) offers an explanatory framework for macro-level comparative analyses of systems of mass education, including their structures, accompanying policies and their curricular and pedagogical practices. WCT has contributed to broader efforts to overcome methodological nationalism in comparative research. In this paper, we…

  17. Inclusion in a Polarised World

    OpenAIRE

    Freeman, Alan

    2005-01-01

    This paper on inclusion was presented to the at the 2005 summer school of DEEEP (Development Education Exchange in Europe Project), Härnösand - Sweden, 5 - 12 June 2005. It addresses the significance of the concept of world civilisation. It assesses how meaning may be attached to the concept of inclusion in an economically polarised world. It develops a critique of the conception of economic inclusion, by means of an exploration of linguistic inclusion and the notion of ‘disability’. ‘...

  18. The USGS World Energy Program

    Science.gov (United States)

    Ahlbrandt, Thomas S.

    1997-01-01

    The world has recently experienced rapid change to market-driven economies and increasing reliance on petroleum supplies from areas of political instability. The interplay of unprecedented growth of the global population, increasing worldwide energy demand, and political instability in two major petroleum exporting regions (the former Soviet Union and the Middle East) requires that the United States maintains a current, reliable, objective assessment of the world's energy resources. The need is compounded by the environmental implications of rapid increases in coal use in the Far East and international pressure on consumption of fossil fuels.

  19. WORLD DELTAS AND THEIR EVOLUTION

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In August 1998, an international symposium on the world deltas was held in New Orleans, Louisiana, USA. This symposium attracted discussion about more than 25 deltas from around the world with emphasis placed on those that are most densely populated and impacted by humans. Keynote papers printed details about the physical, biological, engineering and socioeconomic aspects of six deltas including the Mississippi, Nile, Ganges-Brahmaputra, Rhine-Meuse, Changjiang and Po. The main purpose of this symposium was to inform scientists, engineers and decision-makers about information that is currently available and to provide them a basis for working in such environments.

  20. New Threat to World Economy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The aggregate amount of money and credit in the global economy has risen sharply over the past 30 years,with its growth rate and stock far exceeding that of the real economy or real assets of the world.This is the view of Xiang Songzuo,professor at the Huazhong University of Science and Technology,whose opinion was first published in a recent article in China Business News.Xiang said this situation is a real threat to the world economy.Excerpts of his article are reprinted below:

  1. Population and the World Bank.

    Science.gov (United States)

    Sankaran, S

    1973-12-01

    The World Bank Group regards excessive population growth as the single greatest obstacle to economic and social advance in the underdeveloped world. Since 1969 the Bank and the International Development Agency have provided countries with technical assistance through education, fact-finding, and analysis and given 65.7 million dollars for population projects. These projects, in India, Indonesia, Iran, Jamaica, and Malaysia provide training centers, population education, research, and evaluation as well as actual construction of clinics and mobile units. Because population planning touches sensitive areas of religion, caste, race, morality, and politics, the involved nation's political commitment to plan population growth is critical to the success of any program.

  2. Being in a Virtual World

    DEFF Research Database (Denmark)

    Walther-Hansen, Mads; Grimshaw, Mark

    2016-01-01

    We present a theoretical framework by which virtual world sound designers may work towards the attainment of presence. Drawing on the study of cognitive metaphors and the view that sound is an emergent perception we offer an account of the environment as a salient and dynamic construct that funct......We present a theoretical framework by which virtual world sound designers may work towards the attainment of presence. Drawing on the study of cognitive metaphors and the view that sound is an emergent perception we offer an account of the environment as a salient and dynamic construct...

  3. WORLD

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    1. THE UNITED STATES U.S. President Barack Obama, Israeli Prime Minister Benjamin Netanyahu and President of the Palestinian National Authority Mahmoud Abbas confer during trilateral negotiations on Middle East peace on September 22 in New York

  4. WORLD

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    RUSSIA President Vladimir Putin answers questions during his annua press conference in Moscow on December 18,2014,where he expressed confidence in the nation’s economic prospects FRANCE Police officers inspect the van a driver used to plough into a market thatI resulted in the injuries of at least 10 people before the perpetrator

  5. World

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    USA&EU 美欧新谈判6月17日,美同总统奥巴马与欧盟领导人在英国北爱尔兰厄恩湖举行的八国峰会上联合宣布,美欧正式启动《跨大西洋贸易和投资伙伴关系协定》(TTIP)谈判,并将于今年7月8日举行首轮谈判。

  6. World

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    美联储想“退”了据媒体5月11日报道,关联储正在筹划退出“量比宽松”政策,并将根据就业市场和通胀变化不断调整购债计划。其实,今年2月公布的美联储1月货币政策会议纪要显示,

  7. World

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Russia普京归来弗拉基米尔·普京赢得了自己的第三个俄罗斯总统任期。据报道,俄罗斯中央选举委受会5日在莫斯科公布的初步统计结果显示,在对全国100%选票进行统计后,总统候选人、现任总理普京得票率为63.6%。其他几位候选人的得票率分别如俄罗斯共产党候选人久加诺夫以17.18%的得票率位居第二、独立候选人普罗霍罗夫得票率为7.98%、自由民主党候选人日里诺夫斯基得票率为6.22%、公正俄罗斯党候选人米罗诺夫的得票率为3.85%。

  8. WORLD

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    伦敦吃霸王餐泛滥在伦敦高档餐厅享用霸王餐如今成为一些食客的消费宝典。吃霸王餐的行为在去年11月引起英国民众的关注。除了普通食客,名人也来蹭霸王餐。如电影制片人简尼斯·诺兹在伦敦9家高级餐厅享用了价值约6000英镑的美食后落跑,而最终被警方抓获。事后他除了被罚付清所欠账单以外,还被明令禁止踏入伦敦的各大高档餐馆。

  9. World

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    Sweden 世纪洪水6月初以来,连续的强降雨袭击中东欧地区,德国、奥地利、捷克、匈牙利等国的很多河流水位暴涨,泛滥成灾,部分河流的水位甚至达到了近400年来的峰值。截举6月9日,洪灾已造成至少20人遇难,数万人被迫撤离家同。有媒体将这次洪灾称为“世纪洪水”,多国宣布进入“紧急状态”。

  10. World

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    瑞典女王储大婚5万份中国陶瓷做国礼32岁的瑞典女王储、未来的瑞典女王维多利亚公主与"平民"出身的未婚夫、36岁的韦斯特林前不久在瑞典首都举行婚礼,这场婚礼是近年来欧洲最大的王室盛事,来自世界各地的王室成员和政府首脑悉数列席。王室公布逾950名

  11. World

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    福布斯最富有王室排名公布泰王以300亿美元居首金融危机的若即若离,让各国王室的日子也有好有坏。近日,美国著名的《福布斯》杂志就公布全球最富有王室的最新排名。虽然泰国政治环境动荡不安,但泰国国王普密蓬仍然以300亿美元的资产连续第三年位列王室富豪排行榜之首。

  12. World

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    USA 美国的欧洲时刻过去三年间,美国领导人一直以几乎不加掩饰的蔑视态度旁观欧洲对欧元危机的处理。但从近来美国政客们避免财政悬崖灾难的表现来看,

  13. World

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    欧盟2012首次峰会:通过“财政契约”草案近日,继达沃斯世界经济论坛后,欧盟于布鲁塞尔再开峰会寻求解困方案。与过去10多次峰会相同,这次峰会欧盟领袖持续倡议强化财政纪律足解决欧债危机的唯一途径。

  14. World

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    碳价狂跌从最高峰时的15~20欧元,跌到现在的0.7~0.8欧元一吨,四年时间阁际碳交易价格直跌至“白菜价”。作为《京都议定书》中规定的三个灵活履约机制之一,CDM(清沽发展机制)允许发达国家通过在发展中国家实施具有温室气体减排效果的项目,

  15. World

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    金砖褪色从2010年初至今,巴西工业产出就一直止步不前,3年来倒退了近3%,伴随着工业生产的萎靡不振,投资增速也大幅放缓.政府对保增长的忧虑更是与日俱增。

  16. Teaching World Cultures through Artifacts

    Science.gov (United States)

    Hauf, James E.

    2010-01-01

    Teaching world cultures in the middle-level geography classroom presents challenges both because of the complexity of culture and because of the characteristics of students of this age. One effective way to teach about a culture is through the use of cultural artifacts. This article discusses how to collect and use cultural artifacts in the…

  17. Sustainability in a multipolar world

    NARCIS (Netherlands)

    Basha i Novosejt, A.; Weterings, R.; Ridder, M. de; Frinking, E.

    2010-01-01

    In its 30-Year Update of the well-known publication ‘The Limits to growth’ the Club of Rome stressed that the once debated notion of a physically limited world growth is becoming apparent in many well-documented studies. Three decades ago, the Brundtland Commission on Development and Environment ini

  18. World Input-Output Network.

    Directory of Open Access Journals (Sweden)

    Federica Cerina

    Full Text Available Production systems, traditionally analyzed as almost independent national systems, are increasingly connected on a global scale. Only recently becoming available, the World Input-Output Database (WIOD is one of the first efforts to construct the global multi-regional input-output (GMRIO tables. By viewing the world input-output system as an interdependent network where the nodes are the individual industries in different economies and the edges are the monetary goods flows between industries, we analyze respectively the global, regional, and local network properties of the so-called world input-output network (WION and document its evolution over time. At global level, we find that the industries are highly but asymmetrically connected, which implies that micro shocks can lead to macro fluctuations. At regional level, we find that the world production is still operated nationally or at most regionally as the communities detected are either individual economies or geographically well defined regions. Finally, at local level, for each industry we compare the network-based measures with the traditional methods of backward linkages. We find that the network-based measures such as PageRank centrality and community coreness measure can give valuable insights into identifying the key industries.

  19. Savior of the World Economy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The credit crunch and generally tightened monetary policy caused by the subprime crisis in the United States are still being widely assessed around the globe.Worries are that a further downturn of the U.S.market in the coming year will intensify cash flow shortages and spur more economic losses,resulting in a complete decline of the U.S.market and therefore slowing down the world economy.Another theory has surfaced assuming that China and the United States are the double-barreled engines of the world economy.As China’s influence spreads,it will have to complement the United States to rid the world of this crisis. Ding Yifan,Deputy Director of the Institute of World Development under the Development Research Center of the State Council,has made clear China’s growing impact on the global economy.However,as Ding wrote to the Global Times,a Beijing-based daily publication,the knockdown effect of the mortgage crisis is apparent,and emerging markets look even more vulnerable because of it.Excerpts follow:

  20. Teenagers and their digital world

    NARCIS (Netherlands)

    dr. Guus Wijngaards; Dr. Jos Fransen; Pieter Swager

    2006-01-01

    The Internet and computers increasingly determine our daily lives. This goes for almost everyone in the Netherlands. Still, it is mostly teenagers who are well informed on how to use all the possibilities of new technologies. They are building a digital world of their own that parents usually know

  1. World Input-Output Network

    Science.gov (United States)

    Cerina, Federica; Zhu, Zhen; Chessa, Alessandro; Riccaboni, Massimo

    2015-01-01

    Production systems, traditionally analyzed as almost independent national systems, are increasingly connected on a global scale. Only recently becoming available, the World Input-Output Database (WIOD) is one of the first efforts to construct the global multi-regional input-output (GMRIO) tables. By viewing the world input-output system as an interdependent network where the nodes are the individual industries in different economies and the edges are the monetary goods flows between industries, we analyze respectively the global, regional, and local network properties of the so-called world input-output network (WION) and document its evolution over time. At global level, we find that the industries are highly but asymmetrically connected, which implies that micro shocks can lead to macro fluctuations. At regional level, we find that the world production is still operated nationally or at most regionally as the communities detected are either individual economies or geographically well defined regions. Finally, at local level, for each industry we compare the network-based measures with the traditional methods of backward linkages. We find that the network-based measures such as PageRank centrality and community coreness measure can give valuable insights into identifying the key industries. PMID:26222389

  2. Achieving world class maintenance status

    Energy Technology Data Exchange (ETDEWEB)

    Tomlingson, P.D. [Paul D. Tomingson Associates (United States)

    2007-08-15

    The article written by a management consultant, discusses the art of successful planning and operation of maintenance in mines considering factors such as benchmaking, key performance indices (KPIs) and frequency of procedures which can help achieve 'world class maintenance'. 1 fig.

  3. Witches in the Atlantic World.

    Science.gov (United States)

    Breslaw, Elaine

    2003-01-01

    Presents a lesson plan that focuses on witchcraft in the Atlantic world. Describes each of the four sections of the lesson that encompasses learning about terms and religious views on witchcraft to the history of witchcraft in New England, in the United States, and the Salem (Massachusetts) witchcraft trials. (CMK)

  4. World Wide Web Homepage Design.

    Science.gov (United States)

    Tillman, Michael L.

    This paper examines hypermedia design and draws conclusions about how educational research and theory applies to various aspects of World Wide Web (WWW) homepage design. "Hypermedia" is defined as any collection of information which may be textual, graphical, visual, or auditory in nature and which may be accessed via a nonlinear route.…

  5. Key World Energy Statistics 2012

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Key World Energy Statistics contains timely, clearly-presented data on supply, transformation and consumption of all major energy sources. The interested businessman, journalist or student will have at his or her fingertips the annual Canadian production of coal, the electricity consumption in Thailand, the price of diesel oil in Spain and thousands of other useful energy facts.

  6. World AIDS Day PSA (:30)

    Centers for Disease Control (CDC) Podcasts

    2011-11-16

    December 1 is World AIDS Day. In this PSA, communities are encouraged to get tested for HIV.  Created: 11/16/2011 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 11/16/2011.

  7. Guidelines for a Changing World

    Science.gov (United States)

    Wood, Jo Nell; Brack, Karen

    2011-01-01

    This article investigates the issues surrounding teachers' use of social networking media and their First Amendment rights. It focuses on the need to develop a school district policy outlining specific guidelines for the use of technology and social networking. It also focuses on the changing world of technology and social networking as well as…

  8. PACS for the Developing World

    Directory of Open Access Journals (Sweden)

    Jeffrey B. Mendel

    2015-11-01

    Full Text Available Digital imaging is now firmly ensconced in the developed world. Its widespread adoption has enabled instant access to images, remote viewing, remote consultation, and the end of lost or misplaced film. Unfortunately, the current paradigm of Picture Archiving and Communication System (PACS, with advanced technology inseparable from high complexity, high purchase costs, and high maintenance costs, is not suited for the low-income developing world. Like the simple, easy to repair, 1950’s American cars still running on the streets of Havana, the developing world requires a PACS (DW-PACS that can perform basic functions and survive in a limited-resource environment. The purpose of this article is to more fully describe this concept and to present a blueprint for PACS tailored to the needs and resources of the developing world. This framework should assist both users looking for a vendor-supplied or open-source solutions and developers seeking to address the needs of this emerging market.

  9. World Energy Data Systems (WENDS).

    Science.gov (United States)

    Lareau, William E.

    The World Energy Data System (WENDS) allows qualified users on-line access to non-classified management level data on worldwide energy technology and research and development activities. Information is arranged on textual pages and available by means of a simple accessing procedure. Described in this report are the WENDS concept and approach, the…

  10. Water research for the world

    NARCIS (Netherlands)

    Van Halem, D.

    2013-01-01

    Let’s start with the United Nations Millennium Development Goals Report 2012. Remember the target? Halve, by 2015, the proportion of the population without sustainable access to safe drinking water and basic sanitation. Thanks to China and India the world has met the drinking water target in 2010, b

  11. "My World" with Neil Cavuto

    Science.gov (United States)

    Valenzano, Joseph, Jr.

    2006-01-01

    This article profiles Neil Cavuto, the host of "Your World with Neil Cavuto," who never seems to miss a beat as the poised and impeccably dressed TV journalist who delivers the latest business news, conducts guest interviews, and offers personal commentary. But this 47-year-old newsman has battled not only one, but two life-altering medical…

  12. Addressing the world water crisis

    Science.gov (United States)

    The world is facing an impinging crisis on water as population growth continues, energy use increases, and affluence (standard of living) increases all requiring more water. Agriculture must find ways to use water more productively while improving the impact of agriculture on the environment. Agri...

  13. A light-connected world

    Science.gov (United States)

    Haas, Harald

    2016-08-01

    The humble household light bulb - once a simple source of illumination - could soon be transformed into the backbone of a revolutionary new wireless communications network based on visible light. Harald Haas explains how this “LiFi” system works and how it could shape our increasingly data-driven world

  14. One world of veterinary medicine.

    Science.gov (United States)

    King, L J

    2009-08-01

    The veterinary profession finds itself in the midst of a new world order. Today veterinarians are part of a world that is exquisitely interconnected culturally, economically, socially, and professionally. As a consequence, societal needs and expectations of the profession are more demanding, critical and far-reaching. Veterinarians must play important roles in five intersecting domains of work: public health, bio-medical research, global food safety and security, ecosystem health and the more traditional role of caring for animals. To be successful in this broad and complex range of services and activities, veterinarians must possess an expanded knowledge base, acquire new skills, and develop a new mindset that will ensure their success and excellence in all these domains. The veterinary profession is becoming more fragmented and specialised, and it needs to be brought back together by a single sphere of knowledge or discipline that can serve as an intellectual foundation. The concept of One World of Veterinary Medicine can do just that. With this mindset veterinarians will become better connected to the world around and gain new public recognition and esteem. To achieve this, a special commitment by academic veterinary medicine is, of course, essential. Veterinary schools must lead an educational transformation that reaffirms the social contract of veterinarians and works to align diverse sectors, build a global community, find a common purpose and expand the 21st Century veterinary portfolio of services, activities, and new possibilities.

  15. Mathematics in the Real World.

    Science.gov (United States)

    Borenstein, Matt

    1997-01-01

    The abstract nature of algebra causes difficulties for many students. Describes "Real-World Data," an algebra course designed for students with low grades in algebra and provides multidisciplinary experiments (linear functions and variations; quadratic, square-root, and inverse relations; and exponential and periodic variation)…

  16. The World Bank's ECB Experience.

    Science.gov (United States)

    Mackay, Keith

    2002-01-01

    Focuses on the evaluation capacity building (ECB) outreach activities of the World Bank with regard to provision of advice and assistance to individual governments. The primary story is that of the ECB lessons learned through working with a range of governments; the secondary story is how ECB is becoming a recognized and valued activity within the…

  17. Real-world driving behaviour

    NARCIS (Netherlands)

    Rijkeboer, R.C.; Hendriksen, P.; Gense, N.L.J.

    2001-01-01

    With increasing complexity of engine management system there is a tendency for traditional driving cyles to become further and further removed from reality. So for a sensible evaluation of emissions and fuel consumption of road vehicles in the field there is an urgent need for 'real-world' driving p

  18. Black holes in brane worlds

    Indian Academy of Sciences (India)

    M S Modgil; S Panda; S Sengupta

    2004-03-01

    A Kerr metric describing a rotating black hole is obtained on the three brane in a five-dimensional Randall-Sundrum brane world by considering a rotating five-dimensional black string in the bulk. We examine the causal structure of this space-time through the geodesic equations.

  19. Iowa and World War I.

    Science.gov (United States)

    Hardesty, Carolyn, Ed.

    1989-01-01

    This issue of the children's quarterly magazine, "The Goldfinch," focuses on World War I. A brief discussion of how the United States came to enter the War is followed by a discussion of propaganda. An article on the use of posters to encourage citizens to participate in the war effort is illustrated with reproductions of several of…

  20. World Input-Output Network.

    Science.gov (United States)

    Cerina, Federica; Zhu, Zhen; Chessa, Alessandro; Riccaboni, Massimo

    2015-01-01

    Production systems, traditionally analyzed as almost independent national systems, are increasingly connected on a global scale. Only recently becoming available, the World Input-Output Database (WIOD) is one of the first efforts to construct the global multi-regional input-output (GMRIO) tables. By viewing the world input-output system as an interdependent network where the nodes are the individual industries in different economies and the edges are the monetary goods flows between industries, we analyze respectively the global, regional, and local network properties of the so-called world input-output network (WION) and document its evolution over time. At global level, we find that the industries are highly but asymmetrically connected, which implies that micro shocks can lead to macro fluctuations. At regional level, we find that the world production is still operated nationally or at most regionally as the communities detected are either individual economies or geographically well defined regions. Finally, at local level, for each industry we compare the network-based measures with the traditional methods of backward linkages. We find that the network-based measures such as PageRank centrality and community coreness measure can give valuable insights into identifying the key industries.

  1. Sustainability in a multipolar world

    NARCIS (Netherlands)

    Basha i Novosejt, A.; Weterings, R.; Ridder, M. de; Frinking, E.

    2010-01-01

    In its 30-Year Update of the well-known publication ‘The Limits to growth’ the Club of Rome stressed that the once debated notion of a physically limited world growth is becoming apparent in many well-documented studies. Three decades ago, the Brundtland Commission on Development and Environment ini

  2. Nanotechnology for the developing world

    Energy Technology Data Exchange (ETDEWEB)

    El Naschie, M. Saladin [Department of Physics, University of Alexandria (Egypt); Department of Astrophysics, Cairo University (Egypt); Department of Physics, Mansura University (Egypt)

    2006-11-15

    The letter discusses the indispensable importance of Nanotechnology for the scientific and economical revival of the developing world. Similar to the nuclear age, and maybe far more so, the nanoage will be something of a Hemingway line of demarcation between the have and the have nots.

  3. Teenagers and their digital world

    NARCIS (Netherlands)

    Wijngaards, Guus; Fransen, Jos; Swager, Pieter

    2006-01-01

    The Internet and computers increasingly determine our daily lives. This goes for almost everyone in the Netherlands. Still, it is mostly teenagers who are well informed on how to use all the possibilities of new technologies. They are building a digital world of their own that parents usually know v

  4. The Best of Both World

    DEFF Research Database (Denmark)

    Korsgaard, Steffen; Ferguson, Richard; Gaddefors, Johan

    2015-01-01

    impacts on their opportunity creation. Based on a multiple case study we find that rural entrepreneurs mix what we refer to as placial embeddedness – an intimate knowledge of and concern for the place – with strategically built non-local networks, i.e. the best of two worlds. Notably, the entrepreneurs...

  5. The best of both worlds

    NARCIS (Netherlands)

    Carola Simon; Lotte Vermeij; Anja Steenbekkers

    2007-01-01

    Original title: Het beste van twee werelden. In the eyes of many rural dwellers, the Dutch countryside combines the best of both worlds. They enjoy the peace and quiet, space and landscape around them every day and are happy to live in an environment where people still have time and attention

  6. A Word to the World

    Institute of Scientific and Technical Information of China (English)

    JOHN; BUTCHER

    2007-01-01

    English is undoubtedly the global language, but as China rises ever higher on the world stage, Mandarin is beginning to look like a potential challenger to that title. Satus—it means 'the beginning' in Latin, but how many people would know that?

  7. A Tale of TWO WORLDS

    Institute of Scientific and Technical Information of China (English)

    Gerard Lyons

    2010-01-01

    @@ The global economy is currently a tale of two worlds.A buoyant East contrasts with a fragile West.The difference is highlighted not just in the economic data but also in the monetary policies being pursued around the globe.

  8. Genocide in World History Textbooks.

    Science.gov (United States)

    Fleming, Dan

    1987-01-01

    Analyzes the treatment of genocide in secondary world history textbooks. Acknowledges that textbook space is limited, but argues that all should contain some reference to the subject. Concludes that the Armenian genocide, as well as the genocidal acts of Hitler, Stalin, and Mao Tse-tung should be presented in all survey texts. (GEA)

  9. Paint the World with Light

    Science.gov (United States)

    Gran, David

    2010-01-01

    Two classrooms on opposite sides of the world happened to be working on a very similar project at the same time. In both Shanghai, China, and Palm Springs, California, students were learning how to turn their flashlights and other light-emitting objects into paintbrushes. Light painting is a form of long-exposure photography in which the shutter…

  10. Sustainability in a multipolar world

    NARCIS (Netherlands)

    Basha i Novosejt, A.; Weterings, R.; Ridder, M. de; Frinking, E.

    2010-01-01

    In its 30-Year Update of the well-known publication ‘The Limits to growth’ the Club of Rome stressed that the once debated notion of a physically limited world growth is becoming apparent in many well-documented studies. Three decades ago, the Brundtland Commission on Development and Environment

  11. World Map of Scientific Misconduct.

    Science.gov (United States)

    Ataie-Ashtiani, Behzad

    2017-06-26

    A comparative world map of scientific misconduct reveals that countries with the most rapid growth in scientific publications also have the highest retraction rate. To avoid polluting the scientific record further, these nations must urgently commit to enforcing research integrity among their academic communities.

  12. The Real World Starts Here

    Science.gov (United States)

    Hill, Kimberly A.

    2012-01-01

    The author, principal at North Point High School of Science, Technology and Industry in Charles County, Maryland, describes how the school merges traditional academic classes with cutting-edge career and technical education courses to prepare students for the real world. Realizing that its traditional "vo-tech" model was undersubscribed…

  13. Defying Reality: Performing Reimagined Worlds

    Science.gov (United States)

    Intili, Amanda; Pembleton, Matthew; LaJevic, Lisa

    2015-01-01

    Art educators are concerned with exposing their students to contemporary art making practices. They aim to create fresh lessons that expand their understandings of art in today's world while highlighting the importance of imagination. With a personal interest in performance and street art (art forms that have gained popularity in recent years),…

  14. Prospect of World Petroleum production

    Institute of Scientific and Technical Information of China (English)

    Weng Wenbo

    1994-01-01

    @@ The two former models of world oil and gas production were published in 1984[1] in Chinese text.Almost a decade had now passed. It's time to review whether the 1984 models were still of value to the industry. Let us scrutinize the oil model first.

  15. Enhancing Spiritualism in Virtual World

    Science.gov (United States)

    Dangwal, Kiran Lata; Singh, Shireesh Pal

    2012-01-01

    Spiritualism is one word which puts man on the highest plinth of life. Spirituality is the way we find meaning, hope, comfort and inner peace in life. Spirituality in the virtual World is generally known as Virtual Spirituality. A goldmine of wisdom from all kinds of religious and spiritual philosophies, traditions and practices can be found in…

  16. Defying Reality: Performing Reimagined Worlds

    Science.gov (United States)

    Intili, Amanda; Pembleton, Matthew; LaJevic, Lisa

    2015-01-01

    Art educators are concerned with exposing their students to contemporary art making practices. They aim to create fresh lessons that expand their understandings of art in today's world while highlighting the importance of imagination. With a personal interest in performance and street art (art forms that have gained popularity in recent years),…

  17. World-Wide Information Networks.

    Science.gov (United States)

    Samuelson, Kjell A. H. W.

    The future paths of research and development towards world-wide, automated information networks in full operation are examined. From international networked planning and projects under way it appears that exploratory as well as normative approaches have been taken. To some extent adequate technolgical facilities have already come into existence…

  18. Global Science: Brave New World

    Science.gov (United States)

    Turner, Michael

    2005-04-01

    Scientists have always viewed their activity as one without borders, and they can be rightfully called first adapters of globalization. Be careful what you wish for! While there are great benefits to working together - e.g., tackling bigger problems, traveling to exotic places, and bringing the world closer together - there are challenges too - e.g., more approvals and longer timescales; larger, more diverse collaborations with different customs; meshing not only currencies but accounting systems. It is too late to go back - and I for one would not want to - and the rules have changed forever. In a small world with three similarly economically powerful regions, dominance is impossible - what's important in the Americas will soon become important to Europe and Asia; what's no longer important to Europe and Asia will soon no longer be important to the Americas. Cooperation is encouraged, competition is bad, and duplication cannot be afforded. The biggest challenge of all is coordination/formation of world projects without a ``World Science Foundation." I will use NSF examples to illustrate, including Gemini, IceCube, LHC, and ALMA.

  19. A microbial world within us

    NARCIS (Netherlands)

    Zoetendal, E.G.; Vaughan, E.E.; Vos, de W.M.

    2006-01-01

    The microbial world within us includes a vast array of gastrointestinal (GI) tract communities that play an important role in health and disease. Significant progress has been made in recent years in describing the intestinal microbial composition based on the application of 16S ribosomal RNA (rRNA)

  20. World Wind: NASA's Virtual Globe

    Science.gov (United States)

    Hogan, P.

    2007-12-01

    Virtual globes have set the standard for information exchange. Once you've experienced the visually rich and highly compelling nature of data delivered via virtual globes with their highly engaging context of 3D, it's hard to go back to a flat 2D world. Just as the sawbones of not-too-long-ago have given way to sophisticated surgical operating theater, today's medium for information exchange is just beginning to leap from the staid chalkboards and remote libraries to fingertip navigable 3D worlds. How we harness this technology to serve a world inundated with information will describe the quality of our future. Our instincts for discovery and entertainment urge us on. There's so much we could know if the world's knowledge was presented to us in its natural context. Virtual globes are almost magical in their ability to reveal natural wonders. Anyone flying along a chain of volcanoes, a mid-ocean ridge or deep ocean trench, while simultaneously seeing the different depths to the history of earthquakes in those areas, will be delighted to sense Earth's dynamic nature in a way that would otherwise take several paragraphs of "boring" text. The sophisticated concepts related to global climate change would be far more comprehensible when experienced via a virtual globe. There is a large universe of public and private geospatial data sets that virtual globes can bring to light. The benefit derived from access to this data within virtual globes represents a significant return on investment for government, industry, the general public, and especially in the realm of education. Data access remains a key issue. Just as the highway infrastructure allows unimpeded access from point A to point B, an open standards-based infrastructure for data access allows virtual globes to exchange data in the most efficient manner possible. This data can be either free or proprietary. The Open Geospatial Consortium is providing the leadership necessary for this open standards-based data access

  1. World-leading science with SPIRou - the nIR spectropolarimeter / high-precision velocimeter for CFHT

    CERN Document Server

    Delfosse, X; Kouach, D; Hébrard, G; Doyon, R; Artigau, E; Bouchy, F; Boisse, I; Brun, A S; Hennebelle, P; Widemann, T; Bouvier, J; Bonfils, X; Morin, J; Moutou, C; Pepe, F; Udry, S; Nascimento, J -D do; Alencar, S H P; Castilho, B V; Martioli, E; Wang, S Y; Figueira, P; Santos, N C

    2013-01-01

    SPIRou is a near-infrared (nIR) spectropolarimeter / velocimeter proposed as a new-generation instrument for CFHT. SPIRou aims in particular at becoming world-leader on two forefront science topics, (i) the quest for habitable Earth-like planets around very- low-mass stars, and (ii) the study of low-mass star and planet formation in the presence of magnetic fields. In addition to these two main goals, SPIRou will be able to tackle many key programs, from weather patterns on brown dwarf to solar-system planet atmospheres, to dynamo processes in fully-convective bodies and planet habitability. The science programs that SPIRou proposes to tackle are forefront (identified as first priorities by most research agencies worldwide), ambitious (competitive and complementary with science programs carried out on much larger facilities, such as ALMA and JWST) and timely (ideally phased with complementary space missions like TESS and CHEOPS). SPIRou is designed to carry out its science mission with maximum efficiency and ...

  2. World Engineer’s Convention 2011: Engineers Power the World

    CERN Multimedia

    Yi Ling Hwong (Knowledge Transfer) and Katarina Anthony

    2011-01-01

    Can the increasing global energy consumption be met without intensifying global warming? Do the necessary technical solutions exist, and is the switch to a low-carbon energy supply feasible and financially viable? These crucial questions and many others were dealt with at the 2011World Engineer’s Convention (WEC). CERN was invited to participate in the event, highlighting its significant contribution to global engineering with an exhibition space devoted to the LHC on the convention floor and a keynote speech delivered by CERN’s Director-General.   From 4 – 9 September 2011, more than 2000 engineers and researchers, as well as politicians and business representatives from about 100 countries gathered at the 2011World Engineer’s Convention (WEC). Held in Geneva, Switzerland, they met to discuss solutions for a sustainable energy future. Discussions looked at the development of engineering solutions through a variety of approaches, with ...

  3. Researchers making sense of virtual worlds

    DEFF Research Database (Denmark)

    Reinhard, CarrieLynn D.; Williams, Dmitri; Ho, Caroline

    Virtual worlds, from gaming worlds to social worlds, have gained increasing attention by academics, public organizations and private entrepreneurs.  Much has been said about what virtual worlds are and what they mean to people and society.  However, this panel is interested in how we come to know...

  4. Towards Role Detection in Virtual Worlds

    NARCIS (Netherlands)

    Eickhoff, C.; Lavrenko, V.P.

    2012-01-01

    Virtual worlds are a topic of steadily growing relevance. Some of the providers report user numbers that exceed the population of entire nations in the real world. Virtual worlds typically provide a high degree of complexity, which in some areas approaches the real world's richness of detail. Withou

  5. Unit 148 - World Wide Web Basics

    OpenAIRE

    133, CC in GIScience; Yeung, Albert K.

    2000-01-01

    This unit explains the characteristics and the working principles of the World Wide Web as the most important protocol of the Internet. Topics covered in this unit include characteristics of the World Wide Web; using the World Wide Web for the dissemination of information on the Internet; and using the World Wide Web for the retrieval of information from the Internet.

  6. Lessons from World War I

    Directory of Open Access Journals (Sweden)

    John Scales Avery

    2014-05-01

    Full Text Available The history of World War I is reviewed, starting with a discussion of the development of nationalist movements in Europe. It is pointed out that the global disaster started with a seemingly small operation by Austria, which escalated uncontrollably into an all-destroying conflagration. A striking feature of the war was that none of the people who started it had any idea of what it would be like. Technology had changed the character of war, but old patterns of thought remained in place. We also examine the roots of the war in industrial and colonial competition, and in an arms race. Finally, parallels with current events, and the important lessons for today’s world are discussed.

  7. VACCINES AND IMMUNIZATION: WORLD SITUATION

    Directory of Open Access Journals (Sweden)

    G.H. Brundtland

    2007-01-01

    Full Text Available The last issue of the report «vaccines and immunization: world situation» stresses considerable success in immunization at the global level since the mid 90 s — completely total eradication of poliomyelitis across the world, as well as the drastic reduction of the new measles and tetanus cases among mothers and newborns in some poor countries. The report also briefly describes the progress in the development and implementation of the new life saving vaccines, which may save millions of lives annually. The authors have explained some of the reasons, why the global community should invest in immunization, as well as the perspectives for the use of vaccines and immunization in future.Key words: vaccine, immunization, children.

  8. World's soils are under threat

    Science.gov (United States)

    Montanarella, Luca; Pennock, Daniel Jon; McKenzie, Neil; Badraoui, Mohamed; Chude, Victor; Baptista, Isaurinda; Mamo, Tekalign; Yemefack, Martin; Singh Aulakh, Mikha; Yagi, Kazuyuki; Hong, Suk Young; Vijarnsorn, Pisoot; Zhang, Gan-Lin; Arrouays, Dominique; Black, Helaina; Krasilnikov, Pavel; Sobocká, Jaroslava; Alegre, Julio; Henriquez, Carlos Roberto; de Lourdes Mendonça-Santos, Maria; Taboada, Miguel; Espinosa-Victoria, David; AlShankiti, Abdullah; Kazem AlaviPanah, Sayed; El Mustafa Elsheikh, Elsiddig Ahmed; Hempel, Jon; Camps Arbestain, Marta; Nachtergaele, Freddy; Vargas, Ronald

    2016-02-01

    The Intergovernmental Technical Panel on Soils has completed the first State of the World's Soil Resources Report. Globally soil erosion was identified as the gravest threat, leading to deteriorating water quality in developed regions and to lowering of crop yields in many developing regions. We need to increase nitrogen and phosphorus fertilizer use in infertile tropical and semi-tropical soils - the regions where the most food insecurity among us are found - while reducing global use of these products overall. Stores of soil organic carbon are critical in the global carbon balance, and national governments must set specific targets to stabilize or ideally increase soil organic carbon stores. Finally the quality of soil information available for policy formulation must be improved - the regional assessments in the State of the World's Soil Resources Report frequently base their evaluations on studies from the 1990s based on observations made in the 1980s or earlier.

  9. World Energy Roadmap - A Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Alharthi, A.A.; Alfehaid, M.A.

    2007-07-01

    The dialogue between energy consumers and producers that has been going on for the past fifteen years has revealed the basic parameters of the complex energy scene. While the consumers are concerned with security of supply, the producers have equal concern with access to markets. A common ground for the two groups is sustainable development because both aim at the continuous flow of oil to ensure continued economic growth. Both have valid concerns and share equal responsibility towards the world at large where competitive advantages available to both groups are employed to achieve global sustainable development. The key to achieving this goal in a world of competing and (to some extent) conflicting priorities is not only a sizable and irreversible investment by both groups, but also the desire to relax unwarranted regulations that have hindered progress in the energy industry. (auth)

  10. FISITA 2012 World Automotive Congress

    CERN Document Server

    2013-01-01

    Proceedings of the FISITA 2012 World Automotive Congress are selected from nearly 2,000 papers submitted to the 34th FISITA World Automotive Congress, which is held by Society of Automotive Engineers of China (SAE-China ) and the International Federation of Automotive Engineering Societies (FISITA). This proceedings focus on solutions for sustainable mobility in all areas of passenger car, truck and bus transportation. Volume 8: Vehicle Design and Testing (II) focuses on: •Automotive Reliability Technology •Lightweight Design Technology •Design for Recycling •Dynamic Modeling •Simulation and Experimental Validation •Virtual Design, Testing and Validation •Testing of Components, Systems and Full Vehicle Above all researchers, professional engineers and graduates in fields of automotive engineering, mechanical engineering and electronic engineering will benefit from this book.   SAE-China is a national academic organization composed of enterprises and professionals who focus on research, design a...

  11. Real-World Neuroimaging Technologies

    Science.gov (United States)

    2013-05-10

    specialists to develop and assess BCITs [23]. An important step towards this goal was the release of the commercial product, the Emotiv EPOC (San Francisco...Emotiv Epoc , Quasar DSI (San Diego, CA, USA)). However, there remain several interrelated technical hurdles that still must be overcome for real-world...that involve semi-rigid or stiff spring-based mechanisms for hold- ing electrodes in place, such as the Emotiv EPOC or Quasar DSI models. These

  12. Our love-saturated world

    Institute of Scientific and Technical Information of China (English)

    王盛夏

    2005-01-01

    From time to time,I am told that peple nowadays are more and more self-centered and utilitarian (功利主义的) than before,and the distanoe between hearts is farther.As a result,the world is not filled with are and love as before.Nevertheless,one incident that happened not long before smashes the view I was taught to hold.

  13. Beyond the World Food Summit.

    Science.gov (United States)

    Mulvany, P

    1997-08-01

    While most speakers at the 1996 World Food Summit expressed concern about the injustice that forces more than 800 million people worldwide to live with hunger, some sought solutions through economic and social development while others called for a more liberal marketplace. Among world leaders, only Fidel Castro raised issues and challenges that addressed some of the underlying causes of malnutrition. The Plan of Action that grew out of the Summit has only one measurable commitment, which is to halve the number of undernourished people by 2015. The other six commitments, while diluted, contain important objectives even though they give little emphasis to the underlying causes of poverty or hunger. The Summit process, however, did contribute to the fact that food-related issues are now placed higher on the world agenda because many of these issue were raised by civil service organizations (CSOs) at the Summit's parallel NGO (nongovernmental organization) forum. In fact, one of the most positive outcomes of the Summit may prove to be the increased effectiveness of the CSOs as a result of the creation of improved networks in preparation for the Summit. The CSOs contributed examples of how food security could be improved, published an active site on the World Wide Web, and challenged the statements of governments. In addition to raising trade issues, CSOs also lobbied for sustainable agriculture and agricultural biodiversity. In fact, CSOs may have to set a new action agenda for the formal sector to encourage development of new institutions and new global forums that give NGOs a place at the table.

  14. World Focus on the Moment

    Institute of Scientific and Technical Information of China (English)

    Audrey

    2008-01-01

    @@ Chinese people would never for-get the moment-14:28, on May 12, 2008, as the 8.0-magnitude earthquake shook the whole of Sichuan; at that moment the world's at-tention was focused on the southwest of China - the homeland of the Giant Panda. This rare yet catastrophic natural disaster has resulted in the heavy loss of lives and property throughout the region.

  15. World Hegemony or Maritime Power?

    Science.gov (United States)

    2012-04-10

    January 2012, 2). Fukuyama , Francis . State-Building: Governance and World Order in the 21st Century. Ithica: Cornell University Press, 2004. Gelb...J. Hill, USMC AYll-12 Mentor and Defense ’""’"’""·~ .. ·ttee ... ., ~~·"""·" . Dr. Francis H. Marlo Approved:_IL:::! ~~-::::-:_.J:.-,U

  16. System support for "multiple worlds"

    OpenAIRE

    Smith, Jonathan M.; Gerald Q. Maguire Jr.

    1989-01-01

    Concurrently computing alternative solutions to a problem can be used as a method to improve response time. In order to maintain internal consistency despite differences caused by alternative solution methods, "Multiple Worlds" are created. This paper examines the operating system requirements posed by such a method. Problems include (1) side-effects and (2) combinatorial expldsion in the amount of state which must be preserved. We solve these by process management and an application of "copy...

  17. Swine Flu Threatens the World

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The epidemic spreads from Mexico to other countries at an alarming rate How serious is the swine flu? It is so sensitive that the White House had to reassure reporters that U.S. President Barack Obama is still in good health after visiting Mexico in mid-April. Besides the United States and Canada, swine flu cases have appeared in Europe and Asia. The world now faces a "public health emergency of

  18. Sustainability in a multipolar world

    OpenAIRE

    Basha i Novosejt, A.; Weterings, R.; Ridder, M De; Frinking, E.

    2010-01-01

    In its 30-Year Update of the well-known publication ‘The Limits to growth’ the Club of Rome stressed that the once debated notion of a physically limited world growth is becoming apparent in many well-documented studies. Three decades ago, the Brundtland Commission on Development and Environment initiated an international momentum to secure the needs of both present and future generations through a joint policy agenda for sustainable development. Institutions such as the United Nations played...

  19. Serving the world's poor, profitably.

    Science.gov (United States)

    Prahalad, C K; Hammond, Allen

    2002-09-01

    By stimulating commerce and development at the bottom of the economic pyramid, multi-nationals could radically improve the lives of billions of people and help create a more stable, less dangerous world. Achieving this goal does not require MNCs to spearhead global social-development initiatives for charitable purposes. They need only act in their own self-interest. How? The authors lay out the business case for entering the world's poorest markets. Fully 65% of the world's population earns less than $2,000 per year--that's 4 billion people. But despite the vastness of this market, it remains largely untapped. The reluctance to invest is easy to understand, but it is, by and large, based on outdated assumptions of the developing world. While individual incomes may be low, the aggregate buying power of poor communities is actually quite large, representing a substantial market in many countries for what some might consider luxury goods like satellite television and phone services. Prices, and margins, are often much higher in poor neighborhoods than in their middle-class counterparts. And new technologies are already steadily reducing the effects of corruption, illiteracy, inadequate infrastructure, and other such barriers. Because these markets are in the earliest stages of economic development, revenue growth for multi-nationals entering them can be extremely rapid. MNCs can also lower costs, not only through low-cost labor but by transferring operating efficiencies and innovations developed to serve their existing operations. Certainly, succeeding in such markets requires MNCs to think creatively. The biggest change, though, has to come from executives: Unless business leaders confront their own preconceptions--particularly about the value of high-volume, low-margin businesses--companies are unlikely to master the challenges or reap the rewards of these developing markets.

  20. Why Disturb the World Outside?

    Science.gov (United States)

    Horwood, Bert

    There is an urgent need for young people to learn to know the natural world of which they are a part. Outdoor education is the only means by which people can recover their stone-age identity and discover that they are wildlife, no different in the basics of life than any other species. For most of their story, human beings lived in harmony with…

  1. World Reference Center for Arboviruses.

    Science.gov (United States)

    1985-01-01

    viruses from many parts of the world. 7 %, 1.1%vl ’ e- "., Distribution of reagents. The reference center distributed 970 ampoules of reference sera...eight pools of Culiseta melanura collected during 1984 as part of a field study on Lyme disease and other zoonoses in Connecticut. A ninth strain was...dense amorphous masses, were present also in the cytoplasm. Smooth-surfaced reticula occurred in the cytoplasm and contained viral particles in

  2. Trans World Tidal Gravity Profile.

    Science.gov (United States)

    1984-12-31

    America Curitiba (BraziZ) This station, situated at the Universidade Federal do Parana, in the Instituto de Ciencias Geod6sicas under Professor C...SUL COMPOSANTE VEPTICALE ERESIL 29 40 17S 53 49 22W H 700M P 2M 0 330KM DEPOTS SEDIMENTAIRES SUk BASALTE DEPT* DE INGENIERIA RURAL-UNIV. FED. DE SANTA...PRECAMBRIENIGNEISS * UNIVERSIDADE FEDERAL DO RIO GRANDE DO NORTE - DEPARTAMENTO DE FISICA TRANS WORLD TIDAL GRAVITY PROFILES P. MELCHIOR CENTRO POLITECNICO

  3. Emerging Technology Creator of Worlds

    Science.gov (United States)

    2016-01-01

    Studies Quarterly ♦ Fall 2016 5 Creator of Worlds It is in the fields of biology and medicine, however, that emerging technologies will make the...out of the planning stage and into the demon- stration and usage stages—with achievements in neuroscience, biology , and immunology. In the near future...ends. For example, a recent issue of Smithsonian Magazine asked the question, “The Last Mosquito ?” Scientists have the capabilities to eradicate

  4. Query Migration from Object Oriented World to Semantic World

    Directory of Open Access Journals (Sweden)

    Nassima Soussi

    2016-06-01

    Full Text Available In the last decades, object-oriented approach was able to take a large share of databases market aiming to design and implement structured and reusable software through the composition of independent elements in order to have programs with a high performance. On the other hand, the mass of information stored in the web is increasing day after day with a vertiginous speed, exposing the currently web faced with the problem of creating a bridge so as to facilitate access to data between different applications and systems as well as to look for relevant and exact information wished by users. In addition, all existing approach of rewriting object oriented languages to SPARQL language rely on models transformation process to guarantee this mapping. All the previous raisons has prompted us to write this paper in order to bridge an important gap between these two heterogeneous worlds (object oriented and semantic web world by proposing the first provably semantics preserving OQLto-SPARQL translation algorithm for each element of OQL Query (SELECT clause, FROM clause, FILTER constraint, implicit/ explicit join and union/intersection SELECT queries.

  5. Three Worlds of the Megalithic Observatory Kokino

    Science.gov (United States)

    Cenev, G.

    2011-06-01

    Mountain in its symbolic presentation can be considered as a world axis and place for alliance of three worlds: heavenly world, ours or middle world and underworld. Image of the three worlds represents also intellectual establishment, proportion and unity among Gods, Cosmos and Man. The three observation posts of the Megalithic Observatory Kokino actually are symbols of those three worlds in the ancient people's imagination, defining ritual activities. At the same time, they were used for organizing all agricultural and stock breeding activities of the early agricultural communities in the wider region surrounding the ancient observatory.

  6. STRATOSPHERIC TEMPERATURES AND WATER LOSS FROM MOIST GREENHOUSE ATMOSPHERES OF EARTH-LIKE PLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Kasting, James F.; Kopparapu, Ravi K. [Department of Geosciences, The Pennsylvania State University, State College, PA 16801 (United States); Chen, Howard, E-mail: jfk4@psu.edu, E-mail: hwchen@bu.edu [Department of Astronomy, Boston University, 725 Commonwealth Ave., Boston, MA 02215 (United States)

    2015-11-01

    A radiative-convective climate model is used to calculate stratospheric temperatures and water vapor concentrations for ozone-free atmospheres warmer than that of modern Earth. Cold, dry stratospheres are predicted at low surface temperatures, in agreement with recent 3D calculations. However, at surface temperatures above 350 K, the stratosphere warms and water vapor becomes a major upper atmospheric constituent, allowing water to be lost by photodissociation and hydrogen escape. Hence, a moist greenhouse explanation for loss of water from Venus, or some exoplanet receiving a comparable amount of stellar radiation, remains a viable hypothesis. Temperatures in the upper parts of such atmospheres are well below those estimated for a gray atmosphere, and this factor should be taken into account when performing inverse climate calculations to determine habitable zone boundaries using 1D models.

  7. Models of Polarized Light from Oceans and Atmospheres of Earth-like Extrasolar Planets

    CERN Document Server

    McCullough, P R

    2006-01-01

    Specularly reflected light, or glint, from an ocean surface may provide a useful observational tool for studying extrasolar terrestrial planets. Detection of sea-surface glints would differentiate ocean-bearing terrestrial planets, i.e. those similar to Earth, from other terrestrial extrasolar planets. The brightness and degree of polarization of both sea-surface glints and atmospheric Rayleigh scattering are strong functions of the phase angle of the extrasolar planet. We modify analytic expressions for the bi-directional reflectances previously validated by satellite imagery of the Earth to account for the fractional linear polarization of sea-surface reflections and of Rayleigh scattering in the atmosphere. We compare our models with Earth's total visual light and degree of linear polarization as observed in the ashen light of the Moon, or Earthshine. We predict the spatially-integrated reflected light and its degree of polarization as functions of the diurnal cycle and orbital phase of Earth and Earth-lik...

  8. Mapping Clouds and Terrain of Earth-like Planets from Photometric Variability

    CERN Document Server

    Kawahara, Hajime

    2011-01-01

    We develop an inversion technique of annual scattered light curves to sketch a two-dimensional albedo map of exoplanets. As a test-bed for future observations of extrasolar terrestrial planets, we apply this mapping technique to simulated light curves of a mock Earth-twin. A primary feature in recovered albedo maps traces the annual mean distribution of clouds. To extract information of other surface types, we attempt to reduce the cloud signal by taking difference of two bands. We find that the inversion of reflectivity difference between 0.8-0.9 and 0.4-0.5 micron bands roughly recover the continental distribution, except for high latitude regions persistently covered with clouds and snow. The inversion of the reflectivity difference across the red edge (0.8-0.9 and 0.6-0.7 micron) emphasizes the vegetation features near the equator. The planetary obliquity and equinox can be estimated simultaneously with the mapping under the presence of clouds. We conclude that the photometric variability of the scattered...

  9. The effects of refraction on transit transmission spectroscopy: application to Earth-like exoplanets

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Amit; Meadows, Victoria [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Crisp, Dave, E-mail: amit0@astro.washington.edu [NAI Virtual Planetary Laboratory, Seattle, WA (United States)

    2014-09-01

    We quantify the effects of refraction in transit transmission spectroscopy on spectral absorption features and on temporal variations that could be used to obtain altitude-dependent spectra for planets orbiting stars of different stellar types. We validate our model against altitude-dependent transmission spectra of the Earth from ATMOS and against lunar eclipse spectra from Pallé et al. We perform detectability studies to show the potential effects of refraction on hypothetical observations of Earth analogs with the James Webb Space Telescope NIRSPEC. Due to refraction, there will be a maximum tangent pressure level that can be probed during transit for each given planet-star system. We show that because of refraction, for an Earth-analog planet orbiting in the habitable zone of a Sun-like star only the top 0.3 bars of the atmosphere can be probed, leading to a decrease in the signal-to-noise ratio (S/N) of absorption features by 60%, while for an Earth-analog planet orbiting in the habitable zone of an M5V star it is possible to probe almost the entire atmosphere with minimal decreases in S/N. We also show that refraction can result in temporal variations in the transit transmission spectrum which may provide a way to obtain altitude-dependent spectra of exoplanet atmospheres. Additionally, the variations prior to ingress and subsequent to egress provide a way to probe pressures greater than the maximum tangent pressure that can be probed during transit. Therefore, probing the maximum range of atmospheric altitudes, and in particular the near-surface environment of an Earth-analog exoplanet, will require looking at out-of-transit refracted light in addition to the in-transit spectrum.

  10. Galactic cosmic rays on extrasolar Earth-like planets I. Cosmic ray flux

    CERN Document Server

    Grießmeier, J -M; Stadelmann, A; Grenfell, J L; Atri, D

    2015-01-01

    (abridged abstract) Theoretical arguments indicate that close-in terrestial exoplanets may have weak magnetic fields, especially in the case of planets more massive than Earth (super-Earths). Planetary magnetic fields, however, constitute one of the shielding layers that protect the planet against cosmic-ray particles. In particular, a weak magnetic field results in a high flux of Galactic cosmic rays that extends to the top of the planetary atmosphere. We wish to quantify the flux of Galactic cosmic rays to an exoplanetary atmosphere as a function of the particle energy and of the planetary magnetic moment. We numerically analyzed the propagation of Galactic cosmic-ray particles through planetary magnetospheres. We evaluated the efficiency of magnetospheric shielding as a function of the particle energy (in the range 16 MeV $\\le$ E $\\le$ 524 GeV) and as a function of the planetary magnetic field strength (in the range 0 ${M}_\\oplus$ $\\le$ {M} $\\le$ 10 ${M}_\\oplus$). Combined with the flux outside the planeta...

  11. DETECTING INDUSTRIAL POLLUTION IN THE ATMOSPHERES OF EARTH-LIKE EXOPLANETS

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Henry W. [Harvard College, Cambridge, MA 02138 (United States); Abad, Gonzalo Gonzalez; Loeb, Abraham, E-mail: henrylin@college.harvard.edu, E-mail: ggonzalezabad@cfa.harvard.edu, E-mail: aloeb@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

    2014-09-01

    Detecting biosignatures, such as molecular oxygen in combination with a reducing gas, in the atmospheres of transiting exoplanets has been a major focus in the search for alien life. We point out that in addition to these generic indicators, anthropogenic pollution could be used as a novel biosignature for intelligent life. To this end, we identify pollutants in the Earth's atmosphere that have significant absorption features in the spectral range covered by the James Webb Space Telescope. We focus on tetrafluoromethane (CF{sub 4}) and trichlorofluoromethane (CCl{sub 3}F), which are the easiest to detect chlorofluorocarbons (CFCs) produced by anthropogenic activity. We estimate that ∼1.2 days (∼1.7 days) of total integration time will be sufficient to detect or constrain the concentration of CCl{sub 3}F (CF{sub 4}) to ∼10 times the current terrestrial level.

  12. Modelling the circular polarisation of Earth-like exoplanets: constraints on detecting homochirality

    Science.gov (United States)

    Hogenboom, Michael; Stam, Daphne; Rossi, Loic; Snik, Frans

    2016-04-01

    The circular polarisation of light is a property of electromagnetic radiation from which extensive information can be extracted. It is oft-neglected due to its small signal relative to linear polarisation and the need for advanced instrumentation in measuring it. Additionally, numerical modelling is complex as the full Stokes vector must always be computed. Circular polarisation is commonly induced through the multiple scattering of light by aerosols te{hansen} and multiple reflections of light by rough surfaces te{circplanets}. Most interestingly, distinctive spectral circular polarimetric behaviour is exhibited by light reflected by organisms due to the homochiral molecular structure of all known organisms te{chiralbailey}. Especially fascinating is the unique circular polarimetric behaviour of light reflected by photosynthesising organisms at the absorption wavelength of the chlorophyll pigment te{circpolchar}. This presents the previously unexplored possibility of circular polarimetry as a method for identifying and characterising the presence of organisms, a method which could be applied in the hunt for extraterrestrial life. To date, few telescopes exist that measure circular polarisation and none that have been deployed in space. Observations of the circular polarisation reflected by other planets in the solar system have been made with ground-based telescopes, with significant results te{circplanets}. However, none of these observations have been made at the phase angles at which exoplanets will be observed. Also, none have been made of the Earth, which is the logical starting point for the study of biologically induced circular polarisation signals. This introduces the need for numerical modelling to determine the extent to which circular polarisation is present in light reflected by exoplanets or the Earth. In this study, we model the multiple scattering and reflection of light using the doubling-adding method te{dehaan}. We will present circular polarisation signals for both spatially resolved and spatially unresolved planets, using various atmospheric and surface properties and across a range of phase angles. As a test, the calculated degree of circular polarisation resulting from the multiple scattering of light in an atmosphere with varying properties was compared with results presented by Kawata te{circatmos} and was found to be in agreement. Initial modelling of the atmospheric scattering of light by a planetary disk has shown a presence of degree of circular polarisation in the order of 10-4. This represents a static case with one cloudy hemisphere, one cloudless hemisphere and a Lambertian surface. Results containing varied patchy cloud patterns shall also be presented in a bid to reflect the random nature of planetary cloud cover. We will also present the calculated degree of circular polarisation of planets with various cloud coverage and a circularly polarising surface in order to discover the influence of organisms on the numerical results. {1} {hansen} J. E. {Hansen} and L. D. {Travis}. {Light scattering in planetary atmospheres}. {Space Science Reviews}, 16:527-610, October 1974. {circplanets} J. C. {Kemp} and R. D. {Wolstencroft}. {Circular Polarization: Jupiter and Other Planets}. {Nature}, 232:165-168, July 1971. {chiralbailey} J. {Bailey}. {Circular Polarization and the Origin of Biomolecular Homochirality}. In G. {Lemarchand} and K. {Meech}, editors, {Bioastronomy 99}, volume 213 of {Astronomical Society of the Pacific Conference Series}, 2000. {circpolchar} L. {Nagdimunov}, L. {Kolokolova}, and D. {Mackowski}. {Characterization and remote sensing of biological particles using circular polarization}. {Journal of Quantitative Spectroscopy and Radiative Transfer}, 131:59-65, December 2013. dehaan} J. F. {de Haan}, P. B. {Bosma}, and J. W. {Hovenier}. {The adding method for multiple scattering calculations of polarized light}. {Astronomy and Astrophysics}, 183:371-391, September 1987. {circatmos} Y. {Kawata}. {Circular polarization of sunlight reflected by planetary atmospheres}. {Icarus}, 33:217-232, January 1978.

  13. UV Surface Environment of Earth-like Planets Orbiting FGKM Stars Through Geological Evolution

    CERN Document Server

    Rugheimer, S; Kaltenegger, L; Sasselov, D

    2015-01-01

    The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars at the 1AU equivalent distance for Earth through its geological evolution. We explore four different types of atmospheres corresponding to an early Earth atmosphere at 3.9 Gyr ago and three atmospheres covering the rise of oxygen to present day levels at 2.0 Gyr ago, 0.8 Gyr ago and modern Earth (Following Kaltenegger et al. 2007). In addition to calculating the UV flux on the surface of the planet, we model the biologically effective irradiance, using DNA damage as a proxy for biological damage. We find that a pre-biotic Earth (3.9 Gyr ago) orbiting an F0V star receives 6 times the biologically effective radiation as around the early Sun and 3520 times the modern Earth-Sun levels. A pre-biotic Earth orbiting GJ...

  14. The Atmospheres of Earth-like Planets after Giant Impact Events

    CERN Document Server

    Lupu, R E; Marley, Mark S; Schaefer, Laura; Fegley, Bruce; Morley, Caroline; Cahoy, Kerri; Freedman, Richard; Fortney, Jonathan J

    2014-01-01

    It is now understood that the accretion of terrestrial planets naturally involves giant collisions, the moon-forming impact being a well known example. In the aftermath of such collisions the surface of the surviving planet is very hot and potentially detectable. Here we explore the atmospheric chemistry, photochemistry, and spectral signatures of post-giant-impact terrestrial planets enveloped by thick atmospheres consisting predominantly of CO2, and H2O. The atmospheric chemistry and structure are computed self-consistently for atmospheres in equilibrium with hot surfaces with composition reflecting either the bulk silicate Earth (which includes the crust, mantle, atmosphere and oceans) or Earth's continental crust. We account for all major molecular and atomic opacity sources including collision-induced absorption. We find that these atmospheres are dominated by H2O and CO2, while the formation of CH4, and NH3 is quenched due to short dynamical timescales. Other important constituents are HF, HCl, NaCl, an...

  15. Determination of cloud coverage of Earth-like exoplanets by polarimetry

    Science.gov (United States)

    Rossi, Loïc; Stam, Daphne M.

    2016-10-01

    The properties of clouds in atmospheres of exoplanets will play a key role in the processes determining their radiative balance and climate.They also complicate the detection of chemical species in the atmospheres by flattening the spectra or by creating degeneracies between observables (Kitzmann et al. 2011, Line and Parmentier 2016).Polarimetry promises to be a powerful tool to detect and study exoplanets (Stam et al. 2004). The polarisation of the light scattered by the atmospheres of those planets contains a lot of information about the vertical structure of the atmosphere and about the composition of the clouds (Karalidi et al. 2012) and has already been very successful in the retrieval of atmospheric properties of Venus (Rossi et al. 2015, 2016 in prep).We will show that the degree of polarization of the light scattered by a cloudy exoplanet can be used to discriminate between different types of cloud coverage and to quantify the amount of cloud coverage on the planetary scale. We simulated the disk-integrated polarization of light scattered by exoplanets with various patchy cloud patterns, subsolar clouds and polar cusps. We show that flux and polarization can be used to differentiate between patchy and polar clouds. Observations at various wavelengths in the visible range and of different Stokes parameters would allow to differentiate between cloud coverage and cloud top altitudes.We also propose an observational strategy that could help to retrieve orbital parameters and percentage of cloud coverage with minor ambiguities.

  16. Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets

    CERN Document Server

    Rein, Hanno; Spiegel, David S

    2014-01-01

    The detection of strong thermochemical disequilibrium in the atmosphere of an extrasolar planet is thought to be a potential biosignature. In this article we present a new kind of false positive that can mimic a disequilibrium or any other biosignature that involves two chemical species. We consider a scenario where the exoplanet hosts a moon that has its own atmosphere and neither of the atmospheres is in chemical disequilibrium. Our results show that the integrated spectrum of the planet and the moon closely resembles that of a single object in strong chemical disequilibrium. We derive a firm limit on the maximum spectral resolution that can be obtained for both directly-imaged and transiting planets. The spectral resolution of even idealized space-based spectrographs that might be achievable in the next several decades is in general insufficient to break the degeneracy. Both chemical species can only be definitively confirmed in the same object if absorption features of both chemicals can be unambiguously ...

  17. Feasibility studies for the detection of O{sub 2} in an Earth-like exoplanet

    Energy Technology Data Exchange (ETDEWEB)

    Rodler, Florian; López-Morales, Mercedes [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2014-01-20

    We present the results of simulations on the detectability of O{sub 2} in the atmosphere of Earth twins around nearby low mass stars using high resolution transmission spectroscopy. We explore such detectability with each of the three upcoming Extremely Large Telescopes (ELTs), i.e., GMT, TMT, and E-ELT, and high resolution spectrographs, assuming such instruments will be available in all ELTs. With these simulations we extend previous studies by taking into account atmospheric refraction in the transmission spectrum of the exo-Earth and observational white and red noise contributions. Our studies reveal that the number of transits necessary to detect O{sub 2} in the atmosphere of an Earth twin around an M dwarf is by far higher than the number of transits estimated by Snellen et al. In addition, our simulations show that, when accounting for typical noise levels associated with observations in the optical and near-infrared, the O{sub 2} A band at 760 nm is more favorable for detecting the exoplanetary signal than the O{sub 2} band at 1268 nm for all the spectral types, except M9V. We conclude that, unless unpredicted instrumental limitations arise, the implementation of pre-slit optics such as image slicers appears to be key to significantly improving the yield of this particular science case. However, even in the most optimistic cases, we conclude that the detection of O{sub 2} in the atmosphere of an Earth twin will only be feasible with the ELTs if the planet is orbiting a bright close by (d ≤ 8 pc) M dwarf with a spectral type later than M3.

  18. An Earth-sized planet with an Earth-like density

    DEFF Research Database (Denmark)

    Pepe, Francesco; Cameron, Andrew Collier; Latham, David W.

    2013-01-01

    significantly larger than the Earth. Recently, the planet Kepler-78b was discovered(8) and found to have a radius of only 1.16R(circle plus). Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth...

  19. Tidal Heating of Earth-like Exoplanets around M Stars: Thermal, Magnetic, and Orbital Evolutions

    Science.gov (United States)

    Barnes, R.

    2015-01-01

    Abstract The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low-mass M stars whose radiative habitable zone overlaps with the “tidal zone,” where tidal dissipation is expected to be a significant heat source in the interior. We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a viscoelastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within 0.07 AU circularize before 10 Gyr, independent of initial eccentricity. Once circular, these planets cool monotonically and maintain dynamos similar to that of Earth. Planets forced into eccentric orbits can experience a super-cooling of the core and rapid core solidification, inhibiting dynamo action for planets in the habitable zone. We find that tidal heating is insignificant in the habitable zone around 0.45 (or larger) solar-mass stars because tidal dissipation is a stronger function of orbital distance than stellar mass, and the habitable zone is farther from larger stars. Suppression of the planetary magnetic field exposes the atmosphere to stellar wind erosion and the surface to harmful radiation. In addition to weak magnetic fields, massive melt eruption rates and prolonged magma oceans may render eccentric planets in the habitable zone of low-mass stars inhospitable for life. Key Words: Tidal dissipation—Thermal history—Planetary interiors—Magnetic field. Astrobiology 15, 739–760. PMID:26393398

  20. Tidal Heating of Earth-like Exoplanets around M Stars: Thermal, Magnetic, and Orbital Evolutions.

    Science.gov (United States)

    Driscoll, P E; Barnes, R

    2015-09-01

    The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low-mass M stars whose radiative habitable zone overlaps with the "tidal zone," where tidal dissipation is expected to be a significant heat source in the interior. We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a viscoelastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within 0.07 AU circularize before 10 Gyr, independent of initial eccentricity. Once circular, these planets cool monotonically and maintain dynamos similar to that of Earth. Planets forced into eccentric orbits can experience a super-cooling of the core and rapid core solidification, inhibiting dynamo action for planets in the habitable zone. We find that tidal heating is insignificant in the habitable zone around 0.45 (or larger) solar-mass stars because tidal dissipation is a stronger function of orbital distance than stellar mass, and the habitable zone is farther from larger stars. Suppression of the planetary magnetic field exposes the atmosphere to stellar wind erosion and the surface to harmful radiation. In addition to weak magnetic fields, massive melt eruption rates and prolonged magma oceans may render eccentric planets in the habitable zone of low-mass stars inhospitable for life.

  1. Magnetic fields in Earth-like exoplanets and implications for habitability around M-dwarfs.

    Science.gov (United States)

    López-Morales, Mercedes; Gómez-Pérez, Natalia; Ruedas, Thomas

    2011-12-01

    We present estimations of dipolar magnetic moments for terrestrial exoplanets using the Olson & Christiansen (EPS Lett 250:561-571, 2006) scaling law and assuming their interior structure is similar to Earth. We find that the dipolar moment of fast rotating planets (where the Coriolis force dominates convection in the core), may amount up to ~80 times the magnetic moment of Earth, M ⊕, for at least part of the planets' lifetime. For slow rotating planets (where the force of inertia dominates), the dipolar magnetic moment only reaches up to ~1.5 M [symbol in text]. Applying our calculations to confirmed rocky exoplanets, we find that CoRoT-7b, Kepler-10b and 55 Cnc e can sustain dynamos up to ~18, 15 and 13 M [symbol in text], respectively. Our results also indicate that the magnetic moment of rocky exoplanets not only depends on rotation rate, but also on their formation history, thermal state, age, composition, and the geometry of the field. These results apply to all rocky planets, but have important implications for the particular case of planets in the Habitable Zone of M-dwarfs.

  2. Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets.

    Science.gov (United States)

    Rein, Hanno; Fujii, Yuka; Spiegel, David S

    2014-05-13

    The detection of strong thermochemical disequilibrium in the atmosphere of an extrasolar planet is thought to be a potential biosignature. In this article we present a previously unidentified kind of false positive that can mimic a disequilibrium or any other biosignature that involves two chemical species. We consider a scenario where the exoplanet hosts a moon that has its own atmosphere and neither of the atmospheres is in chemical disequilibrium. Our results show that the integrated spectrum of the planet and the moon closely resembles that of a single object in strong chemical disequilibrium. We derive a firm limit on the maximum spectral resolution that can be obtained for both directly imaged and transiting planets. The spectral resolution of even idealized space-based spectrographs that might be achievable in the next several decades is in general insufficient to break the degeneracy. Both chemical species can only be definitively confirmed in the same object if absorption features of both chemicals can be unambiguously identified and their combined depth exceeds 100%.

  3. An Earth-sized planet with an Earth-like density.

    Science.gov (United States)

    Pepe, Francesco; Cameron, Andrew Collier; Latham, David W; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S; Buchhave, Lars A; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney D; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F M; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaëlle D; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew; Watson, Christopher A

    2013-11-21

    Recent analyses of data from the NASA Kepler spacecraft have established that planets with radii within 25 per cent of the Earth's (R Earth symbol) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined are Kepler-10b (1.42 R Earth symbol) and Kepler-36b (1.49 R Earth symbol), which are both significantly larger than the Earth. Recently, the planet Kepler-78b was discovered and found to have a radius of only 1.16 R Earth symbol. Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth and implies a composition of iron and rock.

  4. Stratospheric Temperatures and Water Loss from Moist Greenhouse Atmospheres of Earth-like Planets

    CERN Document Server

    Kasting, James F; Kopparapu, Ravi Kumar

    2015-01-01

    A radiative-convective climate model is used to calculate stratospheric temperatures and water vapor concentrations for ozone-free atmospheres warmer than that of modern Earth. Cold, dry stratospheres are predicted at low surface temperatures, in agreement with recent 3-D calculations. However, at surface temperatures above 350 K, the stratosphere warms and water vapor becomes a major upper atmospheric constituent, allowing water to be lost by photodissociation and hydrogen escape. Hence, a 'moist greenhouse' explanation for loss of water from Venus, or some exoplanet receiving a comparable amount of stellar radiation, remains a viable hypothesis. Temperatures in the upper parts of such atmospheres are well below those estimated for a gray atmosphere, and this factor should be taken into account when performing 'inverse' climate calculations to determine habitable zone boundaries using 1-D models.

  5. The persistence of oceans on Earth-like planets: insights from the deep-water cycle

    CERN Document Server

    Schaefer, Laura

    2015-01-01

    In this paper we present a series of models for the deep water cycle on super-Earths experiencing plate tectonics. The deep water cycle can be modeled through parameterized convection models coupled with a volatile recycling model. The convection of the silicate mantle is linked to the volatile cycle through the water-dependent viscosity. Important differences in surface water content are found for different parameterizations of convection. Surface oceans are smaller and more persistent for single layer convection, rather than convection by boundary layer instability. Smaller planets have initially larger oceans but also return that water to the mantle more rapidly than larger planets. Super-Earths may therefore be less habitable in their early years than smaller planets, but their habitability (assuming stable surface conditions), will persist much longer.

  6. The Leonard Award Address: On the Difficulties of Making Earth-Like Planets

    Science.gov (United States)

    Taylor, Stuart Ross

    1999-05-01

    Here I discuss the series of events that led to the formation and evolution of our planet to examine why the Earth is unique in the solar system. A multitude of factors are involved. These begin with the initial size and angular momentum of the fragment that separated from a molecular cloud. These are crucial in determining whether a planetary system or a double star develops from the resulting nebula. Another requirement is that there must be an adequate concentration of heavy elements to provide the two percent 'rock' and 'ice' components of the original nebula. An essential step in forming rocky planets in the inner nebula is loss of gas and depletion of volatile elements due to early solar activity, that is linked to the mass of the central star. The lifetime of the gaseous nebula controls the formation of gas giants. In our system, fine timing was needed to form the gas giant, Jupiter before the gas in the nebula was depleted. Although Uranus and Neptune eventually formed cores large enough to capture gas, they missed out and ended as ice giants The early formation of Jupiter is responsible for the existence of the asteroid belt (and our supply of meteorites) and the small size of Mars while the gas giant now acts as a gravitational shield for the terrestrial planets. The Earth and the other inner planets accreted long after the giant planets in a gas-free inner nebula from volatile-depleted planetesimals that were probably already differentiated into metallic cores and silicate mantles. The accumulation of the Earth from such planetesimals was essentially a stochastic process, accounting for the differences among the four rocky inner planets including the startling contrast between those two apparent twins, Earth and Venus. Impact history and accretion of a few more or less planetesimals were apparently crucial. The origin of the Moon by a single massive impact with a body larger than Mars accounts for the obliquity (and its stability) and spin of the Earth in addition to explaining the angular momentum, orbital characteristics and unique composition of the Moon. Plate tectonics, unique among the terrestrial planets, led to the development of the continental crust on the Earth, an essential platform for the evolution of Homo sapiens. Random major impacts have punctuated the geological record, accentuating the directionless course of evolution. Thus a massive asteroidal impact terminated the Cretaceous Period, resulted in the extinction of at least 70% of species living at that time and led to the rise of mammals. This sequence of events that resulted in the formation and evolution of our planet were thus unique within our system. The individual nature of the eight planets is repeated among the 60-odd satellites: no two seem identical. This survey of our solar system raises the question whether the random sequence of events that led to the formation of the Earth are likely to be repeated in detail elsewhere. Preliminary evidence from the 'new planets' is not reassuring. The discovery of other planetary systems has removed the previous belief that they would consist of a central star surrounded by an inner zone of rocky planets and an outer zone of giant planets beyond a few AU. Jupiter-sized bodies in close orbits around other stars probably formed in a similar manner to our giant planets at several AU from their parent star and subsequently migrated inwards becoming stranded in close but stable orbits as 'hot Jupiters', when the nebula gas was depleted. Such events would prevent the formation of terrestrial-type planets in such systems.

  7. Geochemical arguments for an Earth-like Moon-forming impactor

    OpenAIRE

    Dauphas, Nicolas; Burkhardt, Christoph; Warren, Paul H.; Fang-Zhen, Teng

    2014-01-01

    Geochemical evidence suggests that the material accreted by the Earth did not change in nature during Earth's accretion, presumably because the inner protoplanetary disc had uniform isotopic composition similar to enstatite chondrites, aubrites and ungrouped achondrite NWA 5363/5400. Enstatite meteorites and the Earth were derived from the same nebular reservoir but diverged in their chemical evolutions, so no chondrite sample in meteorite collections is representative of the Earth's building...

  8. Tidal heating of Earth-like exoplanets around M stars: Thermal, magnetic, and orbital evolutions

    CERN Document Server

    Driscoll, Peter

    2015-01-01

    The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low mass M stars whose radiative habitable zone overlaps with the "tidal zone". We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a visco-elastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within $0.07$ AU circularize before 10 G...

  9. Limits of photosynthesis in extrasolar planetary systems for earth-like planets.

    Science.gov (United States)

    Franck, S; von Bloh, W; Bounama, C; Steffen, M; Schonberner, D; Schellnhuber, H J

    2001-01-01

    We present a general modeling scheme for investigating the possibility of photosynthesis-based life on extrasolar planets. The scheme focuses on the identification of the habitable zone in main-sequence-star planetary systems with planets of Earth mass and size. Our definition of habitability is based on the long-term possibility of photosynthetic biomass production as a function of mean planetary surface temperature and atmospheric CO2-content. All the astrophysical, climatological, biogeochemical, and geodynamic key processes involved in the generation of photosynthesis-driven life conditions are taken into account. Implicitly, a co-genetic origin of the central star and the orbiting planet is assumed. The numerical solution of an advanced geodynamic model yields realistic look-up diagrams for determining the limits of photosynthesis in extrasolar planetary systems, assuming minimum CO2 levels set by the demand of C4 photosynthesis.

  10. Magnetic Fields in Earth-like Exoplanets and Implications for Habitability around M-dwarfs

    OpenAIRE

    Lopez-Morales, Mercedes; Gomez-Perez, Natalia; Ruedas, Thomas

    2011-01-01

    We present estimations of dipolar magnetic moments for terrestrial exoplanets using the Olson & Christiansen (2006) scaling law and assuming their interior structure is similar to Earth. We find that the dipolar moment of fast rotating planets (where the Coriolis force dominates convection in the core), may amount up to ~80 times the magnetic moment of Earth, M_Earth, for at least part of the planets' lifetime. For very slow rotating planets (where the force of inertia dominates), the dipolar...

  11. An Earth-sized planet with an Earth-like density

    OpenAIRE

    Pepe, Francesco; Cameron, Andrew Collier; Latham, David Winslow; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S.; Buchhave, Lars A.; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F. M.; Gettel, Sara; Harutyunyan, Avet

    2013-01-01

    Recent analyses1–4 of data from the NASA Kepler spacecraft5 have established that planets with radii within 25 per cent of Earth’s (R⊕) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars1. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined6,7 ar...

  12. An Earth-sized planet with an Earth-like density

    CERN Document Server

    Pepe, Francesco; Latham, David W; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S; Buchhave, Lars A; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney D; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F M; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaëlle D; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew; Watson, Christopher A

    2013-01-01

    Kepler-78 (KIC 8435766) was identified by Sanchis-Ojeda et al. (2013) as harbouring a transiting planet of 1.16 times the size of the Earth and an orbital period of only 8.5 hours. While the exquisite Kepler photometry was able to determine its radius and period, the mass of the planet (and thus its mean density) remained unconstrained in the absence of precise radial-velocity measurements. Here we present an accurate mass measurement of Kepler-78b using the HARPS-N spectrograph, recently installed on the Telescopio Nazionale Galileo (INAF) at the Roque de los Muchachos Observatory, La Palma, Spain. These new data yield a mass of 1.86 Earth masses. The resulting mean density of the planet is 5.57 grams per cubic centimetre, which is similar to that of the Earth and implies a composition of iron and rock. Kepler-78b, which orbits a Sun-like star called Kepler 78 located in the Cygnus constellation at a distance of about 400 light years from us, is now the smallest exoplanet for which both the mass and radius a...

  13. The Effects of Refraction on Transit Transmission Spectroscopy: Application to Earth-like Exoplanets

    CERN Document Server

    Misra, Amit; Crisp, Dave

    2014-01-01

    We quantify the effects of refraction in transit transmission spectroscopy on spectral absorption features and on temporal variations that could be used to obtain altitude-dependent spectra for planets orbiting stars of different stellar types. We validate our model against altitude-dependent transmission spectra of the Earth from ATMOS and against lunar eclipse spectra from Palle et al. (2009). We perform detectability studies to show the potential effects of refraction on hypothetical observations of Earth analogs with the James Webb Space Telescope (JWST) Near-Infrared Spectrograph (NIRSPEC). Due to refraction, there will be a maximum tangent pressure level that can be probed during transit for each given planet-star system. We show that because of refraction, for an Earth-analog planet orbiting in the habitable zone of a Sun-like star only the top 0.3 bars of the atmosphere can be probed, leading to a decrease in the signal to noise ratio (SNR) of absorption features by 60%, while for an Earth-analog plan...

  14. The role of dynamics on the habitability of an Earth-like planet

    CERN Document Server

    Pilat-Lohinger, E

    2015-01-01

    From the numerous detected planets outside the Solar system, no terrestrial planet comparable to our Earth has been discovered so far. The search for an Exo-Earth is certainly a big challenge which may require the detections of planetary systems resembling our Solar system in order to find life like on Earth. However, even if we find Solar system analogues, it is not certain that a planet in Earth position will have similar circumstances as those of Earth. Small changes in the architecture of the giant planets can lead to orbital perturbations which may change the conditions of habitability for a terrestrial planet in the habitable zone (HZ). We present a numerical investigation where we first study the motion of test-planets in a particular Jupiter-Saturn configuration for which we can expect strong gravitational perturbations on the motion at Earth position according to a previous work. In this study, we show that these strong perturbations can be reduced significantly by the neighboring planets of Earth. I...

  15. Doppler spectroscopy as a path to the detection of Earth-like planets.

    Science.gov (United States)

    Mayor, Michel; Lovis, Christophe; Santos, Nuno C

    2014-09-18

    Doppler spectroscopy was the first technique used to reveal the existence of extrasolar planetary systems hosted by solar-type stars. Radial-velocity surveys led to the detection of a rich population of super-Earths and Neptune-type planets. The numerous detected systems revealed a remarkable diversity. Combining Doppler measurements with photometric observations of planets transiting their host stars further provides access to the planet bulk density, a first step towards comparative exoplanetology. The development of new high-precision spectrographs and space-based facilities will ultimately lead us to characterize rocky planets in the habitable zone of our close stellar neighbours.

  16. Nutritional rickets around the world.

    Science.gov (United States)

    Prentice, Ann

    2013-07-01

    Nutritional rickets is a major public health problem in many countries of the world. The disease is characterized by deformities of the long bones, enlargement of the wrists and costochondral junctions, hypotonia and, in infants, craniotabes and delayed fontanelle closure. Predominantly caused by severe vitamin D deficiency, rickets can also be associated with hypocalcemic seizures and cardiac failure. First presentation is typically at 6-24 months of age, although hypocalcemia may be evident in younger infants. In many affluent industrialized countries, the prevalence of rickets in the general population diminished after the introduction of clean-air legislation and dietary supplementation. However, in such countries, vitamin-D deficiency rickets has re-emerged in recent years, particularly among groups with limited exposure to UVB-containing sunshine. Infants at risk of rickets tend to be those whose mothers had poor vitamin D status during pregnancy and those exclusively breast-fed for a prolonged period with little skin exposure to UVB. In other countries of the world, the prevalence of rickets can be high, even in regions with abundant year-round UVB-containing sunshine. In general, this is also due to vitamin D deficiency related to limited sun exposure. However, reports from Africa and Asia suggest that there may be other etiological factors involved. Studies in South Africa, Nigeria, The Gambia and Bangladesh have identified rickets in children, typically 3-5 years old at first presentation, in whom plasma 25-hydroxyvitamin D concentrations are higher than those characteristic of primary vitamin D deficiency. Calcium deficiency has been implicated, and in some, but not all, disturbances of phosphate metabolism, renal compromise and iron deficiency may also be involved. Continuing studies of the etiology of nutritional rickets will provide evidence to underpin guidelines for the prevention and treatment of rickets world-wide. This article is part of a

  17. Twinning across the Developing World.

    Directory of Open Access Journals (Sweden)

    Jeroen Smits

    Full Text Available BACKGROUND: Until now, little was known about the variation in incidence of twin births across developing countries, because national representative data was lacking. This study provides the first comprehensive overview of national twinning rates across the developing world on the basis of reliable survey data. METHODS: Data on incidence of twinning was extracted from birth histories of women aged 15-49 interviewed in 150 Demographic and Health Surveys, held between 1987 and 2010 in 75 low and middle income countries. During the interview, information on all live births experienced by the women was recorded, including whether it was a singleton or multiple birth. Information was available for 2.47 million births experienced by 1.38 million women in a period of ten years before the interview. Twinning incidence was measured as the number of twin births per thousand births. Data for China were computed on the basis of published figures from the 1990 census. Both natural and age-standardized twinning rates are presented. RESULTS/CONCLUSIONS: The very low natural twinning rates of 6-9 per thousand births previously observed in some East Asian countries turn out to be the dominant pattern in the whole South and South-East Asian region. Very high twinning rates of above 18 per thousand are not restricted to Nigeria (until now seen as the world's twinning champion but found in most Central-African countries. Twinning rates in Latin America turn out to be as low as those in Asia. Changes over time are small and not in a specific direction. SIGNIFICANCE: We provide the most complete and comparable overview of twinning rates across the developing world currently possible.

  18. Henry David Thoreau's Spiritual World

    Institute of Scientific and Technical Information of China (English)

    马云

    2013-01-01

    Henry David Thoreau was wholeheartedly in love with nature and he devoted almost all his life time to observation, appreciation and study of nature. Thus he formed a deep understanding of nature. In 1845, Thoreau began a two-year and two-month residence at Walden Pond. His life was lonely but full of fragrance. He wanted to live meaningfully, confront the essential facts of life and live a simple life. Based on the review of the literature related to this topic, this paper aims to study Henry David Thoreau’s spiritual world, especially reflected in his famous book-Walden.

  19. Fieldwork Skills in Virtual Worlds

    Science.gov (United States)

    Craven, Benjamin; Lloyd, Geoffrey; Gordon, Clare; Houghton, Jacqueline; Morgan, Daniel

    2017-04-01

    Virtual reality has an increasingly significant role to play in teaching and research, but for geological applications realistic landscapes are required that contain sufficient detail to prove viable for investigation by both inquisitive students and critical researchers. To create such virtual landscapes, we combine DTM data with digitally modelled outcrops in the game engine Unity. Our current landscapes are fictional worlds, invented to focus on generation techniques and the strategic and spatial immersion within a digital environment. These have proved very successful in undergraduate teaching; however, we are now moving onto recreating real landscapes for more advanced teaching and research. The first of these is focussed on Rhoscolyn, situated within the Ynys Mon Geopark on Anglesey, UK. It is a popular area for both teaching and research in structural geology so has a wide usage demographic. The base of the model is created from DTM data, both 1 m LiDAR and 5 m GPS point data, and manipulated with QGIS before import to Unity. Substance is added to the world via models of architectural elements (e.g. walls and buildings) and appropriate flora and fauna, including sounds. Texturing of these models is performed using 25 cm aerial imagery and field photographs. Whilst such elements enhance immersion, it is the use of digital outcrop models that fully completes the experience. From fieldwork, we have a library of photogrammetric outcrops that can be modelled into 3D features using free (VisualSFM and MeshLab) and non-free (AgiSoft Photoscan) tools. These models are then refined and converted in Maya to create models for better insertion into the Unity environment. The finished product is a virtual landscape; a Rhoscolyn `world' that is sufficiently detailed to provide a base not only for geological teaching and training but also for geological research. Additionally, the `Rhoscolyn World' represents a significant tool for those students who are unable to attend

  20. World Congress on Engineering 2014

    CERN Document Server

    Ao, Sio-Iong; Gelman, Len

    2015-01-01

    This volume contains fifty-one revised and extended research articles written by prominent researchers participating in the international conference on Advances in Engineering Technologies and Physical Science (London, UK, 2-4 July, 2014), under the World Congress on Engineering 2014 (WCE 2014). Topics covered include mechanical engineering, bioengineering, internet engineering, wireless networks, image engineering, manufacturing engineering, and industrial applications. The book offers an overview of the tremendous advances made recently in engineering technologies and the physical sciences and their applications, and also serves as an excellent reference for researchers and graduate students working in these fields.