WorldWideScience
 
 
1

Early Life Crises of Habitable Planets  

ScienceCinema

...global warming such such a pressing ...global warming and actually for all climate change problems that ...for the global warming problem ...

2

Lynn Rothschild ? Profile ? Directory ? NASA Astrobiology  

Science.gov (United States)

Southam, G., Rothschild, L. & Westall, F. (2007). The geology and habitability of terrestrial planets: fundamental requirements for life.. In: K.E. Fishbaugh, P. ...

3

Tilt-a-Worlds: Effects of High Rates of Obliquity Change on the Habitability of Extrasolar Planets  

Science.gov (United States)

We explore the impact of obliquity variations on planetary habitability in hypothetical systems with high mutual inclination. For the hypothetical systems, we restrict our exploration to systems consisting of a solar-mass star, an Earth-mass planet at 1 AU, and 1 or 2 giant planets. We verify that these systems are stable for 108 years with N-body simulations. We then calculate the obliquity variations induced by the orbital architecture on the Earth-mass planets. We find that in some cases the spin axes can rotate through 360 degrees in as little as 10,000 years (John is that right? Can you look through the systems and find the most extreme case of obliquity variation?) Next, we run energy balance models (EBM) on the terrestrial planets to assess surface temperature and ice coverage on the planets' oceans. Finally, we explore differences in the outer edge of ...

2011-01-01

4

55 Cancri: Stellar Astrophysical Parameters, a Planet in the Habitable Zone, and Implications for the Radius of a Transiting Super-Earth  

CERN Document Server

The bright star 55 Cancri is known to host five planets, including a transiting super-Earth. The interferometric study presented here yields directly determined values for 55 Cnc's stellar astrophyiscal parameters: $R=0.943 \\pm 0.010 R_{\\odot}$, $T_{\\rm EFF} = 5196 \\pm 24$ K. We use isochrone fitting to determine 55 Cnc's age to be 10.2 $\\pm$ 2.5 Gyr, implying a stellar mass of $0.905 \\pm 0.015 M_{\\odot}$. Our analysis of the location and extent of the system's habitable zone (0.67--1.32 AU) shows that planet f ($M \\sin i = 0.155 M_{Jupiter}$) spends the majority of the duration of its elliptical orbit in the circumstellar habitable zone, where, with moderate greenhouse heating, it could harbor liquid water. Finally, our direct value for 55 Cancri's stellar radius allows for a model-independent calculation of the physical diameter of the transiting super-Earth 55 Cnc e ($\\sim 2.05 \\pm 0.15 ...

2011-01-01

5

The evolution of habitable zones during stellar lifetimes and its implications on the search for extraterrestrial life  

CERN Document Server

A stellar evolution computer model has been used to determine changes in the luminosity L and effective temperature T(e) of single stars during their time on the main sequence. The range of stellar masses investigated was from 0.5 to 1.5 times that of the Sun, each with a mass fraction of metals (metallicity, Z) from 0.008 to 0.05. The extent of each star's habitable zone (HZ) has been determined from its values of L and T(e). These stars form a reference framework for other main sequence stars. All of the 104 main sequence stars known to have one or more giant planets have been matched to their nearest stellar counterpart in the framework, in terms of mass and metallicity, hence closely approximating their HZ limits. The limits of HZ, for each of these stars, have been compared to its giant planet(s)'s range of strong gravitational influence. This allows a quick assessment as to whether Earth-mass ...

2003-01-01

7

Biology and The Future of Mars  

Science.gov (United States)

It is possible that at some time in the future we might recreate a habitable climate on Mars

2004-01-01

9

Asperger Syndrome - What it Feels Like (3)  

Science.gov (United States)

Jake, who has been diagnosed with Asperger syndrome, explains that he has developed a number of ritualistic habits.

2009-04-14

10

planet BAN KI-MOON  

Wastenet

CLIMATE CHANGE Copenhagen: seal the deal ...2 OUR PLANET SEAL THE DEAL UNEP promotes environmentally sound practices globally and in its own activities. ...PaGE 30OUR PLANET SEAL THE DEAL 3

11

Visible Earth: Typhoon Aere  

Science.gov (United States)

NASA's Visible Earth catalog of NASA images and animations of our home planet.

12

Visible Earth: Food Additives  

Science.gov (United States)

Feb 25, 2008 ... NASA's Visible Earth catalog of NASA images and animations of our home planet.

13

Achieving the Goals and Objectives of the 2008 - Astrobiology - NASA  

Science.gov (United States)

... the cinder-like planets in orbit around pulsars, the remnants of massive star evolution) to worlds that are more reassuringly familiar. ...

14

Stem growth habit affects leaf morphology and gas exchange traits in soybean  

British Library Electronic Table of Contents (United Kingdom)

Backgrounds and Aims The stem growth habit, determinate or indeterminate, of soybean, Glycine max, varieties affects various plant morphological and developmental traits. The objective of this study is to identify the effect of stem growth habit in soybean on the stomatal conductance of single leaves in relation to their leaf morphology in order to better understand the ecological and agronomic significance of this plant trait. Methods The stomatal conductance of leaves on the main stem was measured periodically under favourable field conditions to evaluate gmax, defined as the maximum stomatal conductance at full leaf expansion, for four varieties of soybean and their respective determinate or indeterminate near isogenic lines (NILs). Leaf morphological traits including stomatal density, ...

2009-01-01

15

The Galactic Exoplanet Survey Telescope (GEST)  

CERN Document Server

The Galactic Exoplanet Survey Telescope (GEST) will observe a 2 square degree field in the Galactic bulge to search for extra-solar planets using a gravitational lensing technique. This gravitational lensing technique is the only method employing currently available technology that can detect Earth-mass planets at high signal-to-noise, and can measure the frequency of terrestrial planets as a function of Galactic position. GEST's sensitivity extends down to the mass of Mars, and it can detect hundreds of terrestrial planets with semi-major axes ranging from 0.7 AU to infinity. GEST will be the first truly comprehensive survey of the Galaxy for planets like those in our own Solar System.

2002-01-01

16

DARWIN mission proposal to ESA  

CERN Document Server

The discovery of extra-solar planets is one of the greatest achievements of modern astronomy. There are now more than 200 such objects known, and the recent detection of planets with masses approximately 5 times that of Earth demonstrates that extra-solar planets of low mass exist. In addition to providing a wealth of scientific information on the formation and structure of planetary systems, these discoveries capture the interest of both scientists and the wider public with the profound prospect of the search for life in the Universe. We propose an L-type mission, called Darwin, whose primary goal is the study of terrestrial extrasolar planets and the search for life on them. By its very nature, Darwin advances the first Grand Theme of ESA Cosmic Vision. Accomplishing the mission objectives will require collaborative science across disciplines ranging from planet formation and ...

2007-01-01

17

Are Stars with Planets Polluted?  

CERN Document Server

We compare the metallicities of stars with radial velocity planets to the metallicity of a sample of field dwarfs. We confirm recent work indicating that the stars-with-planet sample as a whole is iron rich. However, the lowest mass stars tend to be iron poor, with several having [Fe/H]0.48) that contributes to but does not explain the mass-metallicity trend in the stars-with-planets sample. We use Monte Carlo models to show that adding an average of 6.5 Earth masses of iron to each star can explain both the mass-metallicity and the age-metallicity relations of the stars-with-planets sample. However, for at least one star, HD 38529, there is good evidence that the bulk metallicity is high. We conclude that the observed metallicities and metallicity trends are the result of the interaction of three effects; accretion of about 6 Earth masses of iron rich material, selection effects, and in some cases, ...

2002-01-01

18

2D SPH simulations of a single planet migration in a protoplanetary disc  

Science.gov (United States)

Migration of protoplanets inside an accretion disc of a forming star is the most probable scenario for planetary system formation according to current models. Unsolved problems exist, concerning migration times and mechanisms. We report here the results of a 2D hydrodynamic study within an SPH scheme, analysing migration of an Earth-like or a Jupiter-like planet inside an inviscid sub-Keplerian accretion disc, as a function of the initial specific angular momentum of the infalling accretion disc matter. Particle capture by the protoplanet causes a rapid migration, within a few orbits, for the Earth like planet, and about 104 orbits for the Jupiter like planets. The effect of a planet pseudo-atmosphere is also discussed.

2010-01-01

19

The Effect of Lunar-like Satellites on the Orbital Infrared Light Curves of Earth-analog Planets  

CERN Document Server

We investigate the influence of lunar-like satellites on the infrared orbital light curves of Earth-analog extra-solar planets. Such light curves will be obtained by NASA's Terrestrial Planet Finder (TPF) and ESA's Darwin missions as a consequence of repeat observations to confirm the companion status of a putative planet. We use an energy balance model to calculate disk-averaged infrared (bolometric) fluxes from planet-satellite systems over a full orbital period (one year). The satellites are assumed to lack an atmosphere, have a low thermal inertia like that of the Moon and span a range of plausible radii. The planets are assumed to have thermal and orbital properties that mimic those of the Earth while their obliquities and orbital longitudes of inferior conjunction remain free parameters. Even if the gross thermal properties of the planet can be ...

2008-01-01

20

Scattered Light from Close-in Extrasolar Planets: Prospects of Detection with the MOST Satellite  

CERN Document Server

The ultra-precise photometric space satellite MOST (Microvariability and Oscillations of STars) will provide the first opportunity to measure the albedos and scattered light curves from known short-period extrasolar planets. Due to the changing phases of an extrasolar planet as it orbits its parent star, the combined light of the planet-star system will vary on the order of tens of micromagnitudes. The amplitude and shape of the resulting light curve is sensitive to the planet's radius and orbital inclination, as well as the composition and size distribution of the scattering particles in the planet's atmosphere. To predict the capabilities of MOST and other planned space missions, we have constructed a series of models of such light curves, improving upon earlier work by incorporating more realistic details such as: limb darkening of the star, intrinsic granulation noise in the ...

2003-01-01

 
 
 
 
21

Planetary Microlensing at High Magnification  

CERN Document Server

Simulations of planetary microlensing at high magnification that were carried out on a cluster computer are presented. It was found that the perturbations due to two-thirds of all planets occur in the time interval [-0.5t_FWHM, 0.5t_ FWHM] with respect to the peak of the microlensing light curve, where t_FWHM is typically about 14 hours. This implies that only this restricted portion of the light curve need be intensively monitored for planets, a very significant practical advantage. Nearly all planetary detections in high magnification events will not involve caustic crossings. The position angle, mass and projected orbital radius of a planet may be systematically determined from the planetary deviation. Earth mass planets may be detected with 1-m class telescopes if their projected orbital radii lie within about 1.5 - 2.5 AU. Giant planets are detectable over a much larger region. ...

2002-01-01

22

PREVENTING TOBACCO USE AMONG YOUNG PEOPLE  

UK PubMed Central (United Kingdom)

Preventing tobacco use in youths may be an easier task than helping adults break the habit of smoking and overcome its ill effects. Using experimental procedures based on social work techniques,...Full Text Available

1986-01-01

23

Nutritional status of iodine in pregnant women in Catalonia (Spain): study on hygiene-dietetic habits and iodine in urine  

UK PubMed Central (United Kingdom)

BackgroundIt is a priority to achieve an adequate nutritional status of iodine during pregnancy since iodine deficiency in this population may have repercussions on the mother during...Full Text Available

24

Evolution of feeding specialization in Tanganyikan scale-eating cichlids: a molecular phylogenetic approach  

UK PubMed Central (United Kingdom)

BackgroundCichlid fishes in Lake Tanganyika exhibit remarkable diversity in their feeding habits. Among them, seven species in the genus Perissodus are known for...Full Text Available

25

Climatic changes: a major challenge; Changement climatique: un defi majeur  

Energy Technology Data Exchange (ETDEWEB)

To sensitize the public opinion and change the energy consumption habits, the ADEME (french Agency for the environment and the energy mastership) published a document on the climatic change problem and its consequences. A state of the art of the situation, the international agreements and solutions are provided. (A.L.B.)

2001-07-01

26

Biological variations in Anopheles darlingi and Anopheles gambiae  

UK PubMed Central (United Kingdom)

A remarkable range of variation has been demonstrated in the biting habits of A. darlingi in South America. At the centre of its area of distribution, the species comprises both anthropo-endophilic...Full Text Available

1956-01-01

27

Ionizing Radiation and Life  

British Library Electronic Table of Contents (United Kingdom)

Abstract Ionizing radiation is a ubiquitous feature of the Cosmos, from exogenous cosmic rays (CR) to the intrinsic mineral radioactivity of a habitable world, and its influences on the emergence and persistence of life are wide-ranging and profound. Much attention has already been focused on the deleterious effects of ionizing radiation on organisms and the complex molecules of life, but ionizing radiation also performs many crucial functions in the generation of habitable planetary environments and the origins of life. This review surveys the role of CR and mineral radioactivity in star formation, generation of biogenic elements, and the synthesis of organic molecules and driving of prebiotic chemistry. Another major theme is the multiple layers of shielding of planetary surfaces from th...

2011-01-01

28

Induced plasmon mutations affecting the growth habit of peanuts, A. hypogaea L  

International Nuclear Information System (INIS)

The effectiveness of the acridines ethidium bromide (EB) and acriflavine in inducing plasmon mutations was compared with the alkylating agents ethyl methanesulphonate (EMS) and diethyl sulphate and to #gamma#-rays. The growth habit (trailing versus bunch) of peanuts (A. hypogaea), controlled by genic-cytoplasmic interactions, was utilized. Breeding tests distinguishing nuclear from plasmon mutations were developed and are described in detail. Plasmon mutations were induced, but there were differences in mutation yields between the cultivars and the mutagens. (Auth.).

1978-01-01

29

The physical properties of extra-solar planets  

International Nuclear Information System (INIS)

Tremendous progress in the science of extrasolar planets has been achieved since the discovery of a Jupiter orbiting the nearby Sun-like star 51 Pegasi in 1995. Theoretical models have now reached enough maturity to predict the characteristic properties of these new worlds, mass, radius, atmospheric signatures, and can be confronted with available observations. We review our current knowledge of the physical properties of exoplanets, internal structure and composition, atmospheric signatures, including expected biosignatures for exo-Earth planets, evolution, and the impact of tidal interaction and stellar irradiation on these properties for the short-period planets. We discuss the most recent theoretical achievements in the field and the still pending questions. We critically analyze the different solutions suggested to explain abnormally large radii of a significant fraction of transiting exoplanets. Special attention is ...

2010-01-01

30

The Origin of Life from Primordial Planets  

CERN Document Server

The origin of life and the origin of the universe represent two of the most important problems of science. Both are resolved by hydro-gravitational dynamics (HGD) cosmology (Gibson 1996, Schild 1996, Gibson 2009ab), which predicts frozen primordial hydrogen-helium gas planets in clumps as the dark matter of galaxies. Merging Earth-mass planets formed stars, moons and comets to incubate and cosmically seed the first life. Cometary panspermia (Hoyle and Wickramasinghe 1981, 1982; Wickramasinghe et al. 2009) occurs naturally by HGD mechanisms. Comets and moons are fragments from mergers of stardust covered frozen gas planets in their step-wise growth to star mass. Supernovae from stellar over-accretion of planets produce stardust (C, N, O, P etc.) chemical fertilizer. Planets collect this infected radioactive dust gravitationally, to provide liquid water domains in contact with life ...

2010-01-01

31

Terrestrial Planet Formation in Extra-Solar Planetary Systems  

CERN Document Server

Terrestrial planets form in a series of dynamical steps from the solid component of circumstellar disks. First, km-sized planetesimals form likely via a combination of sticky collisions, turbulent concentration of solids, and gravitational collapse from micron-sized dust grains in the thin disk midplane. Second, planetesimals coalesce to form Moon- to Mars-sized protoplanets, also called "planetary embryos". Finally, full-sized terrestrial planets accrete from protoplanets and planetesimals. This final stage of accretion lasts about 10-100 Myr and is strongly affected by gravitational perturbations from any gas giant planets, which are constrained to form more quickly, during the 1-10 Myr lifetime of the gaseous component of the disk. It is during this final stage that the bulk compositions and volatile (e.g., water) contents of terrestrial planets are set, depending on their feeding zones and the ...

2008-01-01

32

Magnetospheric Emissions from the Planet Orbiting tau Boo: A Multi-Epoch Search  

CERN Document Server

All of the solar system gas giants produce electron cyclotron masers, driven by the solar wind impinging on their magnetospheres. Extrapolating to the planet orbiting tau Boo, various authors have predicted that it may be within the detection limits of the 4-meter wavelength (74 MHz) system on the Very Large Array. This paper reports three epochs of observations of tau Boo. In no epoch do we detect the planet; various means of determining the upper limit to the emission yield single-epoch limits ranging from 135 to 300 mJy. We develop a likelihood method for multi-epoch observations and use it to constrain various radiation properties of the planet. Assuming that the planet does radiate at our observation wavelength, its typical luminosity must be less than about 10^{16} W, unless its radiation is highly beamed into a solid angle Omega << 1 sr. While within the range of luminosities predicted by ...

2007-01-01

33

A ~5 M_earth Super-Earth Orbiting GJ 436?: The Power of Near-Grazing Transits  

CERN Document Server

Most of the presently identified exoplanets have masses similar to that of Jupiter and therefore are assumed to be gaseous objects. With the ever-increasing interest in discovering lower-mass planets, several of the so-called super-Earths (i.e., with masses in the interval 1 M_earth < M < 10 M_earth), which are predicted to be rocky, have already been found. Here we report the possible discovery of a planet around the M-type star GJ 436 with a minimum mass of 4.8+/-0.6 M_earth and a true mass of ~5 M_earth, which makes it the least massive planet around a main-sequence star found to date. In contrast with other discoveries, the planet is identified from its perturbations on an inner Neptune-mass transiting planet (GJ 436b), by pumping eccentricity and producing secular variations in the orbital inclination. Analysis of published radial velocity measurements indeed reveals a ...

2008-01-01

34

A correlation between the heavy element content of transiting extrasolar planets and the metallicity of their parent stars  

CERN Document Server

Nine extrasolar planets with masses between 110 and 430M are known to transit their star. The knowledge of their masses and radii allows an estimate of their composition, but uncertainties on equations of state, opacities and possible missing energy sources imply that only inaccurate constraints can be derived when considering each planet separately. Aims: We seek to better understand the composition of transiting extrasolar planets by considering them as an ensemble, and by comparing the obtained planetary properties to that of the parent stars. Methods: We use evolution models and constraints on the stellar ages to derive the mass of heavy elements present in the planets. Possible additional energy sources like tidal dissipation due to an inclined orbit or to downward kinetic energy transport are considered. Results: We show that the nine transiting planets discovered so far ...

2006-01-01

35

When loss is more (for transmission towers) | SmartPlanet  

Wastenet

... ice, hurricanes, and trees (less likely on high voltage transmission lines ) can bring down above ground power lines. Flooding, Leeching ground ...

36

WP116_EatingThePlanet_Nov2009  

Wastenet

Diet scenarios for 2050 compared to the situation in 2000.19 ...Diets 29 ...Wealthy versus poor country diets 62

37

Viewing the Constellations with Binoculars  

CERN Document Server

A guide to practical astronomy. It introduces the reader to some basic (and some not-so-basic) astronomical concepts, and discusses the stars and their evolution, the planets, nebulae, and distant galaxies

2010-01-01

38

Science Directed Spacecraft Autonomy for Mars Missions - detail  

Science.gov (United States)

The rapidly growing field of remote sensing is beginning to supply massive amounts of high resolution imagery of the earth and other planets. ...

39

Planet Forming Protostellar Disks - NASA Technical Report Server ...  

Science.gov (United States)

terms of 11) numerical models, 2D SPH simulations, and analytic models. The 1D model was useful for determining the evolution over very long timescales. ...

40

Ocean Planet:perils-deforestation - SeaWiFS - NASA  

Science.gov (United States)

Deforestation farther inland causes delayed reactions. When roots no longer hold soil in place, it ends up muddying streams, rivers, and coastal waters. ...

 
 
 
 
41

New Ideas in the Theory of Extrasolar Giant Planets and Brown Dwarfs  

CERN Document Server

We summarize and extend recent work on the theory of extrasolar giant planets (EGPs) and brown dwarfs, paying particular attention to Gliese 229 B, the albedos of EGPs, the compositions of substellar atmospheres, the connections with the giant planets in the solar system, cloud physics, and non-gray spectral synthesis. The role of condensates in altering the optical spectrum of Gliese 229 B is explored, as are the systematics of the reflection spectra from extrasolar giant planets near their primaries. In addition, we discuss the role of convection and disequilibrium chemistry in explaining the anomalous detection of CO in Gliese 229 B. Throughout, we highlight the distinctive chemistry that defines this new class of objects and set goals for future study.

1998-01-01

42

Capturing energy in the air to power electronics | SmartPlanet  

Wastenet

...smart grid applications where you could place them very close to the high-voltage transmission lines , very close to transformers and so on. Photo:...

43

An Input to the UVOIR Panel Of the AASC April ... - PlanetQuest - NASA  

Science.gov (United States)

Binary Star Evolution. The evolution of close binary stars can be very different from that of wide binaries of isolated stars. If the stars are close enough ...

44

2D SPH simulations of planet-disc interactions.  

Science.gov (United States)

Current theories on planetary formation establish that massive objects accrete gaseous envelopes, becoming gaseous planets if the accretion process proceeds before the accretion disc dissolution. One of the unsolved problems is that the planet formation is contextual to their quick migration towards the central star, due to the protoplanets-disc interaction, on a timescale lower by an order of magnitude than that of gas accretion onto the protoplanet. These arguments have been recently broached using N-body and/or Eulerian fluid-dynamics codes, mainly in 2D, or a mixing of them. In this work, 2D simulations with a SPH code are performed, to study the migration of one protoplanet. The goal is to scrutinise the protoplanet dragging as a function of planet's mass.

2009-01-01

45

How common are Earths? How common are Jupiters?  

CERN Document Server

Among the billions of planetary systems that fill the Universe, we would like to know how ours fits in. Exoplanet data can already be used to address the question: How common are Jupiters? Here we discuss a simple analysis of recent exoplanet data indicating that Jupiter is a typical massive planet rather than an outlier. A more difficult question to address is: How common are Earths? However, much indirect evidence suggests that wet rocky planets are common.

2002-01-01

46

Disk's Spiral Arms Point to Possible Planets  

National Aeronautics and Space Administration (NASA)

Simulations of young stellar systems suggest that planets embedded in a circumstellar disk can produce many distinctive structures, including rings, gaps and spiral arms. This video compares computer simulations of hypothetical systems to an image of system SAO 206462 taken by the Subaru Telescope and its HiCIAO instrument. n nCredit: NASA Goddard Space Flight Center/NCSA

2011-10-18

47

APC and KRAS mutations in distal colorectal polyps are related to smoking habits in men: results of a cross-sectional study  

British Library Electronic Table of Contents (United Kingdom)

Background The purpose of this study was (a) to evaluate the association between cigarette smoking and the prevalence of distal colorectal polyps and adenocarcinoma and (b) to analyse genetic alterations representing different molecular pathways of the colorectal carcinogenesis. Methods A total of 623 asymptomatic male (mean age: 53 years; 50?65) car factory workers were included. Information on smoking habits and other lifestyle factors were collected followed by a 60 cm colonoscopy. APC and KRAS mutations and microsatellite status were determined in colorectal lesions (colorectal carcinoma (CRC), hyperplastic (HP) and adenomatous polyps (AP)). Data were analysed using unconditional multiple logistic regression models. Results Smokers had a higher prevalence of AP (OR 2.1; 95% CI 1.2?3.6;...

2011-01-01

48

The effect of type I migration on the formation of terrestrial planets in hot-Jupiter systems  

CERN Document Server

Context: Our previous models of a giant planet migrating through an inner protoplanet/planetesimal disk find that the giant shepherds a portion of the material it encounters into interior orbits, whilst scattering the rest into external orbits. Scattering tends to dominate, leaving behind abundant material that can accrete into terrestrial planets. Aims: We add to the possible realism of our model by simulating type I migration forces which cause an inward drift, and strong eccentricity and inclination damping of protoplanetary bodies. This extra dissipation might be expected to enhance shepherding at the expense of scattering, possibly modifying our previous conclusions. Methods: We employ an N-body code that is linked to a viscous gas disk algorithm capable of simulating: gas accretion onto the central star; gap formation in the vicinity of the giant planet; type II migration of the giant planet; type ...

2007-01-01

49

Energy for Lebanon of tomorrow: paradigm of sustainable development and environment  

International Nuclear Information System (INIS)

An overview of the present status of energy sector in Lebanon and requirements of its future development is presented. The study is based on an economic analysis of needs and energy consumption among the population and on a comparison with other developing countries. Tables and graphs on energy distribution, needs and demands per habitant and national income are included. 3 figs. 3 tabs.

50

Religion as a Natural Phenomenon  

ScienceCinema

...same sort of handle ? religious that we have on global warming or energy policy or ...other words my claim is that we need to study religion the way we study global warming and all the other really serious phenomena on this planet ...

51

Planetpol polarimetry of the exoplanet systems 55 Cnc and tau Boo  

CERN Document Server

We present very sensitive polarimetry of 55 Cnc and tau Boo in an attempt to detect the partially polarised reflected light from the planets orbiting these two stars. 55 Cnc is orbited by a hot Neptune planet (55 Cnc e) at 0.038 AU, a hot Jupiter planet (55 Cnc b) at 0.11 AU, and at least 3 more distant planets. The fractional polarisation of this star is very stable, with a standard deviation in the nightly averaged Stokes Q/I and U/I parameters of 2.2x10^{-6}. We derive upper limits on the geometric albedo, A_G and planetary radius using Monte Carlo multiple scattering simulations of a simple model atmosphere. We assume Rayleigh-like scattering and polarisation behaviour (scaled by the maximum polarisation, p_m at 90 degrees) and pressure insensitive extinction. Atmospheres in which multiple scattering plays only a small role have an almost linear relation between polarisation and A_G. In this case, ...

2008-01-01

52

Integrase-directed recovery of functional genes from genomic libraries  

UK PubMed Central (United Kingdom)

Large population sizes, rapid growth and 3.8 billion years of evolution firmly establish microorganisms as a major source of the planet's biological and genetic diversity. However, up to 99% of the...Full Text Available

2009-09-01

53

Hunting at the highway: traffic noise reduces foraging efficiency in acoustic predators  

UK PubMed Central (United Kingdom)

Noise pollution from human traffic networks and industrial activity impacts vast areas of our planet. While anthropogenic noise effects on animal communication are well documented, we have very limited...Full Text Available

2011-06-07

54

Earthbeat - 25/5/2002: Woodsmoke, Health & the Environment  

Wastenet

...wood smoke, emissions, pollution, heaters, environment, Earthbeat - 25/5/2002: Woodsmoke, Health & the Environment Love that Planet All in the Mind The Buzz Health Report In Conversation Ockhams Razor Science Show The Lab Health Matters Catalyst Quantum ...

55

ESW 2009: The Ocean's Green Machines  

National Aeronautics and Space Administration (NASA)

One tiny marine plant makes life on Earth possible: phytoplankton. These microscopic photosynthetic drifters form the basis of the marine food web, they regulate carbon in the atmosphere, and are responsible for half of the photosynthesis that takes place on this planet.

2010-03-10

56

APSIS - an Artificial Planetary System in Space to probe extra-dimensional gravity and MOND  

CERN Document Server

A proposal is made to test Newton's inverse-square law using the perihelion shift of test masses (planets) in free fall within a spacecraft located at the Earth-Sun L2 point. Such an Artificial Planetary System In Space (APSIS) will operate in a drag-free environment with controlled experimental conditions and minimal interference from terrestrial sources of contamination. We demonstrate that such a space experiment can probe the presence of a "hidden" fifth dimension on the scale of a micron, if the perihelion shift of a "planet" can be measured to sub-arc-second accuracy. Some suggestions for spacecraft design are made.

2006-01-01

57

The influence of soil and coppice cycle on the rooting habit of short rotation poplar and willow coppice  

Energy Technology Data Exchange (ETDEWEB)

The increased demand for renewable energy sources has led to large areas of former agricultural land being proposed for short rotation coppice (SRC) establishment. Concerns expressed over the potential impacts of tree roots on buried archaeological evidence led to a study into the rooting habit of SRC. Roots were exposed in trenches dug within a variety of willow and poplar clonal stands grown on brown earth, pelosol, ground-water gley and surface-water gley soils. Root depths and diameters were recorded in each of the 33 trenches. In total, over 18,000 roots were measured on 264 coppice stools. The rotation length, species and stool location within a block were all found to influence the maximum size of root produced. Soil type had some influence on the root number and depth, but the pattern of root distribution down the soil profile was similar for both species. (author)

2004-06-01

58

Statistical measure of association between smoking and lung cancer in Abakaliki, Ebonyi State Nigeria.  

Science.gov (United States)

The hazards of smoking in relation to lung cancer can never be over emphasized. In recent times shortly after Ebonyi State was created in 1996, the capital territory has increasingly been polluted by either quarry operators, motorcycle (Okada) riders or reckless cigarette smokers and bush burning. To investigate the havoc caused by all these on people, questionnaire was distributed among smokers and non smokers in various areas of specialization and habitations. In measuring the significance of association and the degree of association, a chi2 test and odds ratio method of analysis was employed. The result of the analysis showed that non-smokers do suffer lung cancer. It also revealed that the chances of a smoker to have lung cancer is 1.765 times higher than that of a non-smoker. Analysis also showed that lung cancer depends on age of smokers. It was later discovered that middle aged population are mostly affected, by the reason of chi2 partitioning. This research ...

2009-04-01

59

THE DEVIL AND CUSTOMER RELATIONSHIP MANAGEMENT  

British Library Electronic Table of Contents (United Kingdom)

The paper takes as its starting point the diffusion of ICT applications associated with so-called 'customer relationship management' (CRM). CRM encourages organisations to shift their understanding of customers from an episodic and transaction-based perspective to one that emphasises continuous 'relationship management'. CRM applications thus promise to deliver more, real-time accurate information about consumer habits and behaviours therefore allowing organisations to maximise their extraction of business value. This paper explores the ways in which such inscriptive technologies are not merely referential but also constitutive of contemporary re-presentations and ideals of the consuming subject. Focusing on what we might call the 'digital doubles' of customer relationship management the a...

2010-01-01

60

Planetary protection protecting earth and planets against alien microbes  

International Nuclear Information System (INIS)

Protecting Earth and planets against the invasion of 'alien life forms' is not military science fiction, but it is the peaceful daily job of engineers and scientists of space agencies. 'Planetary Protection' is preventing microbial contamination of both the target planet and the Earth when sending robots on interplanetary space mission. It is important to preserve the 'natural' conditions of other planets and to not bring with robots 'earthly microbes' (forward contamination) when looking for 'spores of extra terrestrial life'. The Earth and its biosphere must be protected from potential extraterrestrial biological contamination when returning samples of other planets to the Earth (backward contamination). The NASA-Caltech Laboratory for Planetary Protection of Dr. Kasthuri Venkateswaran at the Jet Propulsion Laboratory (JPL) (California, USA) routinely monitors and characterizes the microbes of NASA ...

2006-04-01

 
 
 
 
61

Survey for Transiting Extrasolar Planets in Stellar Systems. II. Spectrophotometry and Metallicities of Open Clusters  

CERN Document Server

We present metallicity estimates for seven open clusters based on spectrophotometric indices from moderate-resolution spectroscopy. Observations of field giants of known metallicity provide a correlation between the spectroscopic indices and the metallicity of open cluster giants. We use \\chi^2 analysis to fit the relation of spectrophotometric indices to metallicity in field giants. The resulting function allows an estimate of the target-cluster giants' metallicities with an error in the method of \\pm0.08 dex. We derive the following metallicities for the seven open clusters: NGC 1245, [m/H]=-0.14\\pm0.04; NGC 2099, [m/H]=+0.05\\pm0.05; NGC 2324, [m/H]=-0.06\\pm0.04; NGC 2539, [m/H]=-0.04\\pm0.03; NGC 2682 (M67), [m/H]=-0.05\\pm0.02; NGC 6705, [m/H]=+0.14\\pm0.08; NGC 6819, [m/H]=-0.07\\pm0.12. These metallicity estimates will be useful in planning future extra-solar planet transit searches since planets may form more readily in metal-rich ...

2005-01-01

62

Search for Extra-Terrestrial planets: The DARWIN mission - Target Stars and Array Architectures  

CERN Document Server

The DARWIN mission is an Infrared free flying interferometer mission based on the new technique of nulling interferometry. Its main objective is to detect and characterize other Earth-like planets, analyze the composition of their atmospheres and their capability to sustain life, as we know it. DARWIN is currently in definition phase. This PhD work that has been undertaken within the DARWIN team at the European Space Agency (ESA) addresses two crucial aspects of the mission. Firstly, a DARWIN target star list has been established that includes characteristics of the target star sample that will be critical for final mission design, such as, luminosity, distance, spectral classification, stellar variability, multiplicity, location and radius of the star. Constrains were applied as set by planet evolution theory and mission architecture. Secondly, a number of alternative mission architectures have been evaluated on the basis of interferometer ...

2005-01-01

63

On the Insignificance of Photochemical Hydrocarbon Aerosols in the Atmospheres of Close-in Extrasolar Giant Planets  

CERN Document Server

The close-in extrasolar giant planets (CEGPs) reside in irradiated environments much more intense than that of the giant planets in our solar system. The high UV irradiance strongly influences their photochemistry and the general current view believed that this high UV flux will greatly enhance photochemical production of hydrocarbon aerosols. In this letter, we investigate hydrocarbon aerosol formation in the atmospheres of CEGPs. We find that the abundances of hydrocarbons in the atmospheres of CEGPs are significantly less than that of Jupiter except for models in which the CH$_4$ abundance is unreasonably high (as high as CO) for the hot (effective temperatures $\\gtrsim 1000$ K) atmospheres. Moreover, the hydrocarbons will be condensed out to form aerosols only when the temperature-pressure profiles of the species intersect with the saturation profiles--a case almost certainly not realized in the hot CEGPs atmospheres. Hence our models show ...

2004-01-01

64

How initial and boundary conditions affect protoplanetary migration in a turbulent sub-Keplerian accretion disc: 2D SPH simulations  

CERN Document Server

Current theories on planetary formation establish that giant planet formation should be contextual to their quick migration towards the central star due to the protoplanets-disc interactions on a timescale of the order of $10^5$ years, for objects of nearly 10 terrestrial masses. Such a timescale should be smaller by an order of magnitude than that of gas accretion onto the protoplanet during the hierarchical growing-up of protoplanets by collisions with other minor objects. These arguments have recently been analysed using N-body and/or fluid-dynamics codes or a mixing of them. In this work, inviscid 2D simulations are performed, using the SPH method, to study the migration of one protoplanet, to evaluate the effectiveness of the accretion disc in the protoplanet dragging towards the central star, as a function of the mass of the planet itself, of disc tangential kinematics and of the presence of a planet ...

2009-01-01

65

Hot Nights on Extrasolar Planets: Mid-IR Phase Variations of Hot Jupiters  

CERN Document Server

We present results from Spitzer Space Telescope observations of the mid-infrared phase variations of three short-period extrasolar planetary systems: HD 209458, HD 179949 and 51 Peg. We gathered IRAC images in multiple wavebands at eight phases of each planet's orbit. We find the uncertainty in relative photometry from one epoch to the next to be significantly larger than the photon counting error at 3.6 micron and 4.5 micron. We are able to place 2-sigma upper limits of only 2% on the phase variations at these wavelengths. At 8 micron the epoch-to-epoch systematic uncertainty is comparable to the photon counting noise and we detect a phase function for HD 179949 which is in phase with the planet's orbit and with a relative peak-to-trough amplitude of 0.00141(33). Assuming that HD 179949b has a radius R_J < R_p < 1.2R_J and a small Bond albedo, it must recirculate less than 30% of incident stellar energy to its night side at the 1-sigma ...

2007-01-01

66

Protoplanetary Disks of Binary Systems in Orion  

CERN Document Server

Dusty primordial disks surrounding young low-mass stars are revealing tracers of stellar and planetary formation. The evolution and lifetime of these disks define the boundary conditions of the mechanisms of planet formation. Stellar companions, however, can significantly change this evolution through their tidal interactions. Stellar evolution and planet formation in binaries have to respond to an environment of truncated, quickly disappearing disks--very different compared to an isolated star environment. In order to investigate details of the influence of binarity on circumstellar disk evolution, we obtained adaptive optics supported near-infrared imaging and spectroscopy of the individual components of 22 low-mass binaries in the well-known Orion Nebula Cluster. Brackett gamma emission, which we detect in several systems, is used as a tracer for the presence of an active accretion disk around each binary component. We find a low fraction of ...

2010-01-01

67

Mutual interactions of two planetary objects in a protoplanetary accretion disc: 2D SPH simulations .  

Science.gov (United States)

We present here a study based on the migration of protoplanets in an accretion disc of a forming star, as the mainly proposed scenario for the formation of planetary systems. Attention is here focused on the mutual interactions between two protoplanets, both embedded in the accretion disc, as a function of the protoplanets masses, their relative positions, the dynamic properties of the accretion disc particles. The study is performed through a 2D SPH code and preliminary results show an oscillation of the distance between the two protoplanets, together with a slow migration of the two planets towards the central star when two Jupiter-like planets are considered. Less correlated behaviour is observed when at least one of the two protoplanets has an Earth-like mass. The role played by the disc particles initial angular momentum is discussed.

2010-01-01

68

Comparative planetology, climatology and biology of Venus, Earth and Mars  

British Library Electronic Table of Contents (United Kingdom)

Spacecraft studies of the three terrestrial planets with atmospheres have made it possible to make meaningful comparisons that shed light on their common origin and divergent evolutionary paths. Early in their histories, all three apparently had oceans and extensive volcanism; Mars and Earth, at least, had magnetic fields, and Earth, at least, had life. All three currently have climates determined by energy balance relationships involving carbon dioxide, water and aerosols, regulated by solar energy deposition, atmospheric and ocean circulation, composition, and cloud physics and chemistry. This paper addresses the extent to which current knowledge allows us to explain the observed state of each planet, its planetology, climatology and biology, within a common framework. Areas of ignorance...

2011-01-01

69

Volcano Field Trip  

Science.gov (United States)

This site focuses on the subject of volcanoes, including how volcanoes form, the destruction they can cause, effects of volcanoes on the environment, where active volcanoes are found, volcanoes of other planets, and the different volcano types. Designed as an electronic tour, it guides the user through different web sites and outlines teaching objectives, concepts covered, and new vocabulary. There is a teacher resources section with links for more information, and questions for students to answer along the way.

70

Urban Atmospheric Science  

Environmental Research Database

DescriptionThis new research programme activity on Urban Atmospheric Science will deliver aspects of the NERC strategy: Next Generation Science for Planet Earth. It has been developed as part of the Environment, Pollution & Human Health theme. Research in the Environment, Pollution & Human Health theme is directed at elucidating key environmental processes that form part of a causal pathway between an environmental hazard and disease outcome, and providing a predictive capability of the risk to human heal [continued...

2012-01-01

71

Solyndra Loan Guarantee Announcement  

ScienceCinema

...prediction of involvement and saying hasta la vista to global warming and also be a celebrating president obama ...too late to save our planet from the perils of global warming ? john f. kennedy once said ...grandchildren and say we did little to stop the advance of global warming ? we will make a difference ...

72

Smart Takes - Archive: April 2011 | SmartPlanet  

Wastenet

... April 29, 2011, 8:25 AM PDT | By Andrew Nusca Ottawa taps Itron for 210,000 smart water meters The City of Ottawa has chosen smart grid firm Itron ...to deploy smart water meters and related infrastructure in town. April 29, 2011, 7:18 AM PDT | By Andrew ...

73

NAI: Year 4 Annual Report - NASA Astrobiology Institute  

Science.gov (United States)

His talk was based on the suggestion that life on Earh has been a long but accelerating ..... a New Class of Submarine Hydrothermal System"; April 29, 2002 , ..... of media personnel, including radio, television, newspapers, and magazines. ...... "The Birth of Stars and Planets" (Denver Museum of Nature and Science ...

74

Fibre optic grating sensors for biofuels  

Science.gov (United States)

Biofuels will have more intense impact on the energetic grid of the planet, because known fossil fuels reserves are being exhausted. The biofuel production relies on the transformation process of some organic material in the desired hydrocarbon product. Because of the natural characteristics of the related processes, fibre optic sensors appear to be adequate candidates to be used.

2010-09-01

75

100 billion suns  

Energy Technology Data Exchange (ETDEWEB)

A work on the world of astrophysics primarily for lay readers. The author writes only about the discoveries he ''experienced'' during the past 25 years (before 1979). Illustrated somewhat in color plus a set of superb colar plates. Contents, abridged: The long life of stars. The life story of the sun. The life story of massive stars. The end of stars. How stars are born. Planets and their inhabitants.

1983-01-01

76

Studies on the appearance of skeletal anomalies in red porgy: effect of culture intensiveness, feeding habits and nutritional quality of live preys  

British Library Electronic Table of Contents (United Kingdom)

Summary Despite the great interest of red porgy as a new species for Mediterranean aquaculture, its commercial production is constrained by the high incidence of skeletal deformities occurring in this species under culture conditions. Several studies have been conducted to better understand the origin of these anomalies in this species, using different system intensiveness, rotifers enrichment products or rotifers docosahexaenoic acid content. The first study showed that culture intensification increased the number of fish with an extra vertebrae, what was probably related to the different nutritional quality of live preys employed in each treatment, since water temperature, salinity and genetic background were identical for the different batches of fish studied. Total incidence of skeleta...

2010-01-01

77

Problematic of atmospheric pollution in Lebanon: the better stake is apprehended, the best acts are taken  

International Nuclear Information System (INIS)

Lebanon has imported in 1996 5000 Kt of carburants causing about 80 Kt of SO_x; 40 Kt of NO_x; 3 Kt of dusts and 3.5 million tons of CO_2. The atmospheric pollution in Lebanon is due to three main sources: - Thermal central of electric production - Industries (cement) - Transportation sector The document describes in tables: the inventory of pollutants and pollutant emissions in 1993 and 2010; industrial and heating gas oil; liquified petroleum gas commercial propane; fuel oil for EDL; consumption of energy in 1996; sectorial distribution of pollutants PPM; emissions of CO_2 per tons per habitant in 1993; consumption in 1993 broken down by use and application. Finally, three projects concerning public transportation were presented

1999-06-02

78

People of the ancient rainforest: Late Pleistocene foragers at the Batadomba-lena rockshelter, Sri Lanka  

British Library Electronic Table of Contents (United Kingdom)

Batadomba-lena, a rockshelter in the rainforest of southwestern Sri Lanka, has yielded some of the earliest evidence of Homo sapiens in South Asia. H. sapiens foragers were present at Batadomba-lena from ca. 36,000 cal BP to the terminal Pleistocene and Holocene. Human occupation was sporadic before the global Last Glacial Maximum (LGM). Batadomba-lena's Late Pleistocene inhabitants foraged for a broad spectrum of plant and mainly arboreal animal resources (monkeys, squirrels and abundant rainforest snails), derived from a landscape that retained equatorial rainforest cover through periods of pronounced regional aridity during the LGM. Juxtaposed hearths, palaeofloors with habitation debris, postholes, excavated pits, and animal and plant remains, including abundant Canarium nutshells, ref...

2011-01-01

79

Cause analysis and preventives for human error events in Daya Bay NPP  

International Nuclear Information System (INIS)

Daya Bay Nuclear Power Plant is put into commercial operation in 1994 Until 1996, there are 368 human error events in operating and maintenance area, occupying 39% of total events. These events occurred mainly in the processes of maintenance, test equipment isolation and system on-line, in particular in refuelling and maintenance. The author analyses root causes for human errorievents, which are mainly operator omission or error procedure deficiency; procedure not followed; lack of training; communication failures; work management inadequacy. The protective measures and treatment principle for human error events are also discussed, and several examples applying them are given. Finally, it is put forward that key to prevent human error event lies in the coordination and management, person in charge of work, and good work habits of staffs.

80

Optical SETI with Air Cerenkov Telescopes  

CERN Document Server

We propose using large Air Cerenkov Telescopes (ACT's) to search for optical, pulsed signals from extra-terrestrial intelligence. Such dishes collect tens of photons from a nanosecond-scale pulse of isotropic equivalent power of tens of solar luminosities at a distance of 100 pc. The field of view for giant ACT's can be on the order of ten square degrees, and they will be able to monitor 10 to 10$^2$ stars simultaneously for nanosecond pulses of about 6th mag or brighter. Using the Earth's diameter as a baseline, orbital motion of the planet could be detected by timing the pulse arrival times.

2001-01-01

 
 
 
 
81

Nitridosilicates and Oxonitridosilicates: From Ceramic Materials to Structural and Functional Diversity  

British Library Electronic Table of Contents (United Kingdom)

Abstract Silicates are one of the most important classes of compounds on this planet, and more than 1000 silicates have been identified in the mineral kingdom. Additionally, several hundreds of artificial silicates have been synthesized. The substitution of oxygen by nitrogen leads to the structurally diverse and manifold class of nitridosilicates. Silicon nitride, one of the most important non-oxidic ceramic materials, is the binary parent compound of nitridosilicates, and it symbolizes the inherent material properties of these refractory compounds. However, prior to the last decades, a broad systematic investigation of nitridosilicates had not been accomplished. In the meantime, these and related compounds have reached a remarkable level of industrial application. This review illustrates...

2011-01-01

82

Le LHC, un projet mondial  

CERN Multimedia

Since the mid-1980s the number of scientists from all over the world using CERN's facilities has increased enormously. Currently more than 6,000 users, over half of the planet's high-energy physicists, carry out fundamental research at CERN. This user community is living proof that CERN welcomes inter- regional collaboration which benefits all and boosts the progress of science. The LHC, the only machine capable of addressing problems way beyond today's frontiers of high energy physics, offers an unique opportunity for extending world wide collaboration.

1994-01-01

83

ON THE POSSIBILITY OF ENRICHMENT AND DIFFERENTIATION IN GAS GIANTS DURING BIRTH BY DISK INSTABILITY  

International Nuclear Information System (INIS)

We investigate the coupling between rock-size solids and gas during the formation of gas giant planets by disk fragmentation in the outer regions of massive disks. In this study, we use three-dimensional radiative hydrodynamic simulations and model solids as a spatial distribution of particles. We assume that half of the total solid fraction is in small grains and half in large solids. The former are perfectly entrained with the gas and set the opacity in the disk, while the latter are allowed to respond to gas drag forces, with the back reaction on the gas taken into account. To explore the maximum effects of gas-solid interactions, we first consider 10 cm size particles. We then compare these results to a simulation with 1 km size particles, which explores the low-drag regime. We show that (1) disk instability planets have the potential to form large cores due to aerodynamic capturing of rock-size solids in spiral arms before fragmentation; ...

2010-11-20

84

The formation of vertically aligned biaxial tungsten nanorods using a novel shadowing growth technique  

International Nuclear Information System (INIS)

Biaxially textured tungsten nanorods (A15 crystal structure) have been grown by oblique angle DC magnetron sputtering using a novel rotation mode called 'two-step rotation'. In this mode, the substrate is given a fast rotation through 1800 at 90 rpm and this is followed by a rest period of 30 s. These nanorods are vertically aligned and have a [100] texture normal to the substrate along with preferential in-plane texture as shown by x-ray pole figure analysis. In contrast, the tungsten nanorods obtained without substrate rotation are slanted at an angle of ?450 and have a [100] texture tilted 160 with respect to the substrate normal. The flux is incident from two diametrically opposite points on the sample at an oblique angle, averaging out the growth into vertical columns that retain the in-plane texture. Scanning electron microscopy shows that the tungsten nanorods have a mixture of {211} and {421} crystal habits; these planes are both minimum surface energy ...

2009-11-18

85

Epidemiologic studies of coronary heart disease and stroke in Japanese men living in Japan, Hawaii, and California: demographic, physical, dietary, and biochemical characteristics  

International Nuclear Information System (INIS)

These summary descriptive data of ethnically similar cohorts of indigenous and migrant Japanese males have shown similarities or slight differences in characteristics wholly or largely genetically determined, such as blood groups, stature, and skeletal size. Differences have been noted in characteristics largely environmental or behavioral, such as diet and cigarette smoking habit, as well as in characteristics determined by a varying mixture of genetic and environmental influences, such as weight, blood pressure, glucose tolerance, and serum lipid and uric acid levels. Detailed analyses of the distributions of laboratory variables, of dietary data obtained by different methods, and of correlations among laboratory, dietary, physical, and demographic variables are currently in progress. Also part of the study plan are determinations of disease prevalence from evaluation of examination, laboratory, and electrocardiographic findings, of disease incidence from repeat ...

86

Diesel engine exhaust and lung cancer: An unproven association  

Science.gov (United States)

The risk of lung cancer associated with diesel exhaust has been calculated from 14 case-control or cohort studies. We evaluated the findings from these studies to determine whether there is sufficient evidence to implicate diesel exhaust as a human lung carcinogen. Four studies found increased risks associated with long-term exposure, although two of the four studies were based on the same cohort of railroad workers. Six studies were inconclusive due to missing information on smoking habits, internal inconsistencies, or inadequate characterization of diesel exposure. Four studies found no statistically significant association. It can be concluded that short-term exposure to diesel engine exhaust (20 years) increases the risk of lung cancer for locomotive engineers, brakemen, and diesel engine mechanics. There is inconsistent evidence on the effects of long-term exposure to diesel exhaust in the trucking industry. There is no evidence for a joint effect of diesel ...

1995-09-01

87

Comparison of radon exposure assessment results: {sup 210}Po surface activity on glass objects vs. contemporary air radon concentration  

Energy Technology Data Exchange (ETDEWEB)

Radon exposure assessment in case-control studies on radon and lung cancer is generally based on contemporary radon concentration measurements, which can be affected by significant changes in the building structures or in living habits. Another method to estimate the radon exposure of the subjects is the recently developed retrospective dosimetry technique based on the {sup 210}Po surface activity from glass objects. In order to compare the results obtained by the two methods, a study has been carried out in a sample of 26 dwellings in Rome, with radon concentration values ranging from 28 to 623 Bq m{sup -3}. Retrospective detectors based on CR-39 and LR 115 were exposed on 50 glass objects in bedrooms and living rooms. The correlation factor between the two sets of data, after removing six extreme values, is 0.67, which is similar to results obtained in other validation studies of similar sample size. The correlation increases to 0.83 if the 21 objects exposed in ...

2003-06-01

88

Bioavailability of lead in rats fed human diets  

International Nuclear Information System (INIS)

The bioavailability of lead was studied in rats fed various baby foods (Babymix-turkey, Babymix-vegetables, Frutolino-fruit, Frutamix-bananas, Babyron-S-26, Truefood), cow's milk, bread, liver and standard rat diet. Lead absorption was determined by measuring the whole body retention of "2"0"3Pb 6 days after a single oral application. Highest absorption values ranging from 17 to 20% were obtained in animals fed cow's milk and fruit foods. Rats on other human diets absorbed between 3 and 8% of the radioactive lead dose. Only in animals on rat diet lead absorption was below 1%. It is concluded that rats fed human diets show absorption values similar to those in humans. This might indicate that the bioavailability of lead is primarily dependent on dietary habits. This experimental model, if confirmed by further work, might be useful for obtaining preliminary data on the bioavailability of metals from various foods.

89

Why the Universe is Just So  

CERN Document Server

Some properties of the universe are fixed by physics derived from mathematical symmetries, others may have been selected from an ensemble of possibilities. Some successes and failures of anthropic reasoning in this context are reviewed in the light of recent developments in astrobiology, cosmology and unification physics. Specific issues raised include our spacetime location (including the reason for the present age of the universe), the timescale of biological evolution, the tuning of global cosmological parameters, the origin of the Large Numbers of astrophysics, and the parameters of the Standard Model. Out of the twenty parameters of the Standard Model,the basic behavior and structures of the world (nucleons, nuclei,atoms, molecules, planets, stars, galaxies) depend mainly on five of them: $m_e,m_u,m_d,\\alpha,\\alpha_G$, three of which are independent in the context of Grand Unified Theories (that is, not related by any known symmetry). These parameters also ...

2000-01-01

90

The Challenges of Multidisciplinary Education in Computer Science  

British Library Electronic Table of Contents (United Kingdom)

Some of the most important problems facing the United States and China, indeed facing our entire planet, require approaches that are fundamentally multidisciplinary in nature. Many of those require skills in computer science (CS), basic understanding of another discipline, and the ability to apply the skills in one discipline to the problems of another. Modern training in computer science needs to prepare students to work in other disciplines or to work on multidisciplinary problems. What do we do to prepare them for a multidisciplinary world when there are already too many things we want to teach them about computer science? This paper describes successful examples of multidisciplinary education at the interface between CS and the biological sciences, as well as other examples involving C...

2011-01-01

91

Strategies to Promote High School Students’ Healthful Food Choices  

British Library Electronic Table of Contents (United Kingdom)

Studies have suggested that skill-building through hands-on cooking as a nutrition education strategy, is effective to improve overall dietary quality among participants. FamilyCook Productions' ''Diet for a Healthy Planet with Teen Battle Chefs(TM)'' curriculum using this approach, was piloted in 2008 in a Brooklyn public high school resulting in a statistically significant improvements in dietary quality as well as attitudinal improvements and efforts by students to support changes in school food service. Program evaluation used the RE-AIM framework and employed both quantitative and qualitative strategies including pre and post program surveys, focus groups, and weekly electronic teacher feedback. The program has since grown to over 85 high schools in 16 states.

2011-01-01

92

Native Synthetic Imaging of Smoothed Particle Hydrodynamics density fields using gridless Monte Carlo Radiative Transfer  

CERN Document Server

An algorithm for creating synthetic telescope images of Smoothed Particle Hydrodynamics (SPH) density fields is presented, which utilises the adaptive nature of the SPH formalism in full. The imaging process uses Monte Carlo Radiative Transfer (MCRT) methods to model the scattering and absorption of photon packets in the density field, which then exit the system and are captured on a pixelated image plane, creating a 2D image (or a 3D datacube, if the photons are also binned by their wavelength). The algorithm is implemented on the density field directly: no gridding of the field is required, allowing the density field to be described to an identical level of accuracy as the simulations that generated it. Some applications of the method to star and planet formation simulations are presented to illustrate the advantages of this new technique, and suggestions as to how this framework could support a Radiative Equilibrium algorithm are also given as an indication for ...

2010-01-01

93

Cloud Formation and Dynamics in Cool Dwarf and Hot Exoplanetary Atmospheres  

CERN Document Server

The lowest-mass stars, brown dwarfs and extrasolar planets present challenges and opportunities for understanding dynamics and cloud formation processes in low-temperature atmospheres. For brown dwarfs, the formation, variation and rapid depletion of photospheric clouds in L- and T-type dwarfs, and spectroscopic evidence for non-equilibrium chemistry associated with vertical mixing, all point to a fundamental role for dynamics in vertical abundance distributions and cloud/grain formation cycles. For exoplanets, azimuthal heat variations and the detection of stratospheric and exospheric layers indicate multi-layered, asymmetric atmospheres that may also be time-variable (particularly for systems with highly elliptical orbits). Dust and clouds may also play an important role in the thermal energy balance of exoplanets through albedo effects. For all of these cases, 3D atmosphere models are becoming an increasingly essential tool for understanding spectral and ...

2009-01-01

94

Atmospheric chemistry on Venus, Earth, and Mars: Main features and comparison  

British Library Electronic Table of Contents (United Kingdom)

This paper deals with two common problems and then considers major aspects of chemistry in the atmospheres of Mars and Venus. (1) The atmospheres of the terrestrial planets have similar origins but different evolutionary pathways because of the different masses and distances to the Sun. Venus lost its water by hydrodynamic escape, Earth lost CO"2 that formed carbonates and is strongly affected by life, Mars lost water in the reaction with iron and then most of the atmosphere by the intense meteorite impacts. (2) In spite of the higher solar radiation on Venus, its thermospheric temperatures are similar to those on Mars because of the greater gravity acceleration and the higher production of O by photolysis of CO"2. O stimulates cooling by the emission at 15@mm in the collisions with CO"2. ...

2011-01-01

95

Deforestation of Rondonia, Brazil, from 1975 to 2001  

Science.gov (United States)

Throughout much of the 1980s, deforestation in Brazil eliminated more than 15,000 square kilometers (9000 square miles) per year. That pace has only increased through the 90s and into the 21st century. Brazil is also home to more than a quarter of Earths tropical forests. Considering that the band of lush green that circles the globe through many equatorial nations is fundamental to the overall health of the whole planets environment, careful monitoring of forest health in the tropics is essential. Tropical forests act as major carbon sinks, places where ambient carbon dioxide in the atmosphere can be absorbed by growing things and sequestered for years. Definitive evidence shows that excess carbon dioxide can contribute to the greenhouse effect and speed global warming. Similarly, tropical forests also act as a primary producer of oxygen. In the respiration process that absorbs gaseous carbon dioxide, trees and other plants give off oxygen. It is for these and a ...

2001-04-19

96

Risk analysis for the resident bald eagles of the lower Columbia River  

Energy Technology Data Exchange (ETDEWEB)

The resident bald eagles of the lower Columbia River have lower productivity and higher contaminant levels than other bald eagles of the Pacific Northwest. The primary population stressors are believed to be habitat loss, human disturbance, p,p{prime}DDE, PCBs, dioxins and furans. The primary effect of habitat loss is to reduce the carrying capacity of the region for nesting sites, and the primary effects of human disturbance and contamination by organic compounds are to reduce productivity. The purpose of this study was to quantitatively evaluate the effects of all of, these potential stressors on the bald eagle population dynamics. A model of the population dynamics was developed. The model structure includes a physiologically-based toxicokinetic (PBTK) submodel to estimate the degree of contamination, which is linked via a toxicology submodel to a population dynamics submodel. The PBTK submodel is time-variable, incorporating species-specific bioenergetics, as well as contaminant ...

1995-12-31

97

Cs-137 concentrations in the muscles of Walleye Pollack  

International Nuclear Information System (INIS)

High concentrations of Cs-137 were detected in the muscles of Walleye Pollack (Theragra chalcogramm) collected from Kitamiyamato banks (sampling on 25 Jul. 2000), Kamui area (16 Oct. 2000) and Niigata coasts (31 Jan. 2001). The concentrations were 0.35 #+-# 0.01, 0.41 #+-# 0.01, and 0.63 #+-# 0.02 Bq/kg-wet, respectively. The average concentration in our past investigations was about 0.25 #+-# 0.01 Bq/kg-wet. Samples from other areas, the coat of Kushiro (8 May 2001), North Tishima (13 Nov. 2000) and the Sea of Okhotsk (6 May 2001), had the average concentrations. There were no such high concentrations of Cs-137 in other fish species collected from Kitamiyamato banks, Kamui area, and Niigata coasts. Fish samples with high concentrations all make the migration in the north of Japan sea. These results would indicated that samples took in Cs-137 elements from sea-water or foods on the migration route. Cs-137 concentrations in muscles of walleye pollack does not increase with the body ...

2003-08-17

98

The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III  

Energy Technology Data Exchange (ETDEWEB)

The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly{alpha} forest, and a radial velocity search for planets around {approx}8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes 5-band imaging of roughly 5200 deg{sup 2} in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg{sup 2}, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of ...

2011-01-01

99

Tau Boo b: Hunting for reflected starlight  

CERN Document Server

Aims. We attempt to detect starlight reflected from the hot Jupiter orbiting the main-sequence star Tau Boo, in order to determine the albedo of the planetary atmosphere, the orbital inclination of the planetary system and the exact mass of the planetary companion. Methods. We analyze high-precision, high-resolution spectra, collected over two half nights using UVES at the VLT/UT2, by way of data synthesis. We interpret our data using two different atmospheric models for hot Jupiters. Results. Although a weak candidate signal appears near the most probable radial velocity amplitude, its statistical significance is insufficient for us to claim a detection. However, this feature agrees very well with a completely independently obtained result by another research group, which searched for reflected light from Tau Boo b. As a consequence of the non-detection of reflected light, we place upper limits to the planet-to-star flux ratio at the 99.9% significance level. For ...

2010-01-01

100

Studying the atmosphere of the exoplanet HAT-P-7b via secondary eclipse measurements with EPOXI, Spitzer and Kepler  

CERN Document Server

The highly irradiated transiting exoplanet, HAT-P-7b, currently provides one of the best opportunities for studying planetary emission in the optical and infrared wavelengths. We observe six near-consecutive secondary eclipses of HAT-P-7b at optical wavelengths with the EPOXI spacecraft. We place an upper limit on the relative eclipse depth of 0.055% (95% confidence). We also analyze Spitzer observations of the same target in the infrared, obtaining secondary eclipse depths of 0.098+/-0.017%, 0.159+/-0.022%, 0.245+/-0.031% and 0.225+/-0.052% in the 3.6, 4.5, 5.8 and 8.0 micron IRAC bands respectively. We combine these measurements with the recently published Kepler secondary eclipse measurement, and generate atmospheric models for the day-side of the planet that are consistent with both the optical and infrared measurements. The data are best fit by models with a temperature inversion, as expected from the high incident flux. The models predict a low optical albedo ...

2009-01-01

 
 
 
 
101

Stalking the ultimate particle  

CERN Multimedia

If you missed the ARTE programme entitled "L'Ultime Particule" broadcast in February, you have another chance to catch it in CERN's Main Auditorium on 13 March. "L'Ultime Particule" is a documentary by the French director Michel Andrieu that seeks to explain particle physics through a contemplative quest for the research physicists of matter of today and yesteryear. Invariably kitted out in a red parka and a soft hat, the programme's investigator scours the planet and the archives in search of the research physicists who are stalking the ultimate particle, the Higgs boson, in their quest to understand the structure of matter. Naturally enough, CERN is an important stage of his journey where Michel Andrieu and his team spent several days last year. Both from the physics and metaphysical points of view, "L'Ultime Particule" is worth seeing. The film's director, Michel Andrieu, will introduce his documentary and answer questions from the audience after the ...

2003-01-01

102

Physics through the 1990s: scientific interfaces and technological applications  

Energy Technology Data Exchange (ETDEWEB)

The volume examines the scientific interfaces and technological applications of physics. Twelve areas are dealt with: biological physics--biophysics, the brain, and theoretical biology; the physics-chemistry interface--instrumentation, surfaces, neutron and synchrotron radiation, polymers, organic electronic materials; materials science; geophysics--tectonics, the atmosphere and oceans, planets, drilling and seismic exploration, and remote sensing; computational physics--complex systems and applications in basic research; mathematics--field theory and chaos; microelectronics--integrated circuits, miniaturization, future trends; optical information technologies--fiber optics and photonics; instrumentation; physics applications to energy needs and the environment; national security--devices, weapons, and arms control; medical physics--radiology, ultrasonics, NMR, and photonics. An executive summary and many chapters contain recommendations regarding funding, ...

1986-01-01

103

On the origin of the Trojan asteroids Effects of Jupiter's mass accretion and radial migration  

CERN Document Server

We present analytic and numerical results which illustrate the effects of Jupiter's accretion of nebular gas and the planet's radial migration on its Trojan companions. Initially, we approximate the system by the planar circular restricted three-body problem and assume small Trojan libration amplitudes. Employing an adiabatic invariant calculation, we show that Jupiter's thirty-fold growth from a $10 M_\\oplus$ core to its present mass causes the libration amplitudes of Trojan asteroids to shrink by a factor of about 2.5 to $\\sim 40%$ of their original size. The calculation also shows that Jupiter's radial migration has comparatively little effect on the Trojans; inward migration from 6.2 to 5.2 AU causes an increase in Trojan libration amplitudes of $\\sim4%$. In each case, the area enclosed by small tadpole orbits, if made dimensionless by using Jupiter's semimajor axis, is approximately conserved. Similar adiabatic invariant calculations for inclined and ...

2000-01-01

104

Infrared Observations During the Secondary Eclipse of HD 209458b I. 3.6-Micron Occultation Spectroscopy Using the VLT  

CERN Document Server

We search for an infrared signature of the transiting extrasolar planet HD 209458b during secondary eclipse. Our method, which we call `occultation spectroscopy,' searches for the disappearance and reappearance of weak spectral features due to the exoplanet as it passes behind the star and later reappears. We argue that at the longest infrared wavelengths, this technique becomes preferable to conventional `transit spectroscopy'. We observed the system in the wing of the strong nu-3 band of methane near 3.6 microns during two secondary eclipses, using the VLT/ISAAC spectrometer at a spectral resolution of 3300. Our analysis, which utilizes a model template spectrum, achieves sufficient precision to expect detection of the spectral structure predicted by an irradiated, low-opacity (cloudless), low-albedo, thermochemical equilibrium model for the exoplanet atmosphere. However, our observations show no evidence for the presence of this spectrum from the exoplanet, with ...

2003-01-01

105

Impact of the Sea Empress oil spill on lysosomal stability in mussel blood cells  

Energy Technology Data Exchange (ETDEWEB)

Coastal zones are among the most productive and vulnerable areas on the planet. An example of impact on these fragile environments was shown in the case of the Sea Empress oil tanker, which ran aground in the Bristol Channel in 1996, spilling 72,000 tonnes of Forties crude oil. The objective was to investigate the sub-lethal cellular pathology and tissue hydrocarbon contamination in marine mussel populations, 4 months after the initial spill, using the neutral red retention (NRR) assay for lysosomal stability in blood cells. NRR was reduced in mussels, and indicative of cell injury, from the two sites closest to the spill in comparison with more distant and reference sites. Lysosomal stability was inversely correlated with polycyclic aromatic hydrocarbon concentrations in mussel tissues. Reduced lysosomal stability has previously been shown to contribute to impaired immunocompetence and to autophagic loss of body tissues. The use of this type of technique is ...

2000-07-01

106

Historical on the Norm Related to the CO{sub 2} Emission Integrated in the Protocol of Kyoto; Historico sobre la Normativa Relacionada con las Emisiones de CO{sub 2} Integrado en el Protocolo de Kyoto  

Energy Technology Data Exchange (ETDEWEB)

The United Nations Framework Convention on Climate Change (UNFCCC) was approved in 1992 to respond to the worl-wide concern about the warming of the planet. The primary target was the stabilization of the concentration of greenhouse gases in the atmosphere, in an attempt to reduce to the minimum the degradation of the environment caused by humans. By virtue of the Convention, the Parts2 are committed to reach their objectives in the reduction of the emissions. A Conference of the Parts was stablished to promote the effective application of the Convention. The third Conference of the Parts, celebrated in Kyoto (Japan, 1997) approved, by consensus, the denominated Kyoto Protocol, in which 39 developed countries and countries with economies in transition were committed to reduce their emissions of greenhouse gases between years 2008 and 2012 in a 5.2 global percent with respect to the 1990 levels. Three {sup f}lexibility mechanisms{sup w}ere stablished to help the ...

2006-07-01

107

HD 75289Ab revisited - Searching for starlight reflected from a hot Jupiter  

CERN Document Server

Aims. We attempt to detect starlight reflected from a hot Jupiter, orbiting the main-sequence star HD 75289Ab. We report a revised analysis of observations of this planetary system presented previously by another research group. Methods. We analyse high-precision, high-resolution spectra, collected over four nights using UVES at the VLT/UT2, by way of data synthesis. We try to interpret our data using different atmospheric models for hot Jupiters. Results. We do not find any evidence for reflected light, and, therefore, establish revised upper limits to the planet-to-star flux ratio at the 99.9% significance level. At high orbital inclinations, where the best sensitivity is attained, we can limit the relative reflected radiation to be less than e = 6.7 x 10-5 assuming a grey albedo, and e = 8.3 x 10-5 assuming an Class IV function, respectively. This implies a geometric albedo smaller than p = 0.46 and p = 0.57, for the grey albedo and the Class IV albedo shape, ...

2008-01-01

108

First detection of polarized scattered light from an exoplanetary atmosphere  

CERN Document Server

We report the first direct detection of an exoplanet in polarized scattered light. The transiting planet HD189733b is one of the very hot Jupiters with shortest periods and, thus, smallest orbits, which makes them ideal candidates for polarimetric detections. We obtained polarimetric measurements of HD189733 in the $B$ band well distributed over the orbital period and detected two polarization maxima near planetary elongations with the peak amplitude of $\\sim2\\cdot10^{-4}$. Assuming Rayleigh scattering, we estimated the effective size of the scattering atmosphere (Lambert sphere) to be 1.5$\\pm$0.2 $R_{\\rm J}$, which is 30% larger than the radius of the opaque body previously inferred from transits. If the scattering matter fills the planetary Roche lobe, the lower limit of the geometrical albedo can be estimated as 0.14. The phase dependence of polarization indicates that the planetary orbit is oriented almost in the north-south direction with the longitude of ...

2007-01-01

109

Establishing the scientific and mechanistic framework for a GIN (Genetic Improvement Network)  

Environmental Research Database

Objectives7. (b) Objectives General background Livestock production accounts for 70% of the agricultural land on the planet. Given that demand for livestock products is expected to double by 2050 it is vital that we identify less polluting ways of production, spanning both intensive and extensive systems. Northern Europe is one of the few parts of the globe where climate change is expected to be neutral or even benefit agricultural productivity. Hence it is likely to make an even more important co [continued...]DescriptionRuminant genetic improvement can play an important role in developing livestock systems that will be sustainable in the future, and produce food in an environmentally friendly manner. Also, genetic improvement of livestock is a particularly cost-effective technology, producing permanent and cumulative changes in performance. Moran et al (2007) showed the very high value of animal and plant genetics research and development in helping to deliver on ...

2010-01-31

110

Collisions with ice-volatile objects: Geological implications  

International Nuclear Information System (INIS)

The collision of the Earth with extra-terrestrial ice-volatile bodies is proposed as a mechanism to produce rapid changes in the geologic record. These bodies would be analogs of the ice satellites found for the Jovian planets and suspected for comets and certain low density bodies in the Asteroid belt. Five generic end-members are postulated: (1) water ice; (2) dry ice: carbon-carbon dioxide rich, (3) oceanic (chloride) ice; (4) sulfur-rich ice; (5) ammonia hydrate-rich ice; and (6) clathrate: methane-rich ice. Due to the volatile nature of these bodies, evidence for their impact with the Earth would be subtle and probably best reflected geochemically or in the fossil record. Actual boloids impacting the Earth may have a variable composition, generally some admixture with water ice. However for discussion purposes, only the effects of a dominant component will be treated. The general geological effects of such collisions, as a function of the dominant component ...

1988-10-20

111

An Upper Limit on the Albedo of HD 209458b: Direct Imaging Photometry with the MOST Satellite  

CERN Document Server

We present space-based photometry of the transiting exoplanetary system HD 209458 obtained with the MOST (Microvariablity and Oscillations of STars) satellite, spanning 14 days and covering 4 transits and 4 secondary eclipses. The HD 209458 photometry was obtained in MOST's lower-precision Direct Imaging mode, which is used for targets in the brightness range $6.5 < V < 13$. We describe the photometric reduction techniques for this mode of observing, in particular the corrections for stray Earthshine. We do not detect the secondary eclipse in the MOST data, to a limit in depth of 0.053 mmag (1 \\sigma). We set a 1 \\sigma upper limit on the planet-star flux ratio of 4.88 x 10^-5 corresponding to a geometric albedo upper limit in the MOST bandpass (400 to 700 nm) of 0.25. The corresponding numbers at the 3 \\sigma level are 1.34 x 10^-4 and 0.68 respectively. HD 209458b is half as bright as Jupiter in the MOST bandpass. This low geometric albedo value is an ...

2006-01-01

112

A search for electron cyclotron maser emission from compact binaries  

CERN Document Server

Unipolar induction (UI) is a fundamental physical process, which occurs when a conducting body transverses a magnetic field. It has been suggested that UI is operating in RX J0806+15 and RX J1914+24, which are believed to be ultra-compact binaries with orbital periods of 5.4 min and 9.6 min respectively. The UI model predicts that those two sources may be electron cyclotron maser sources at radio wavelengths. Other systems in which UI has been predicted to occur are short period extra-solar terrestrial planets with conducting cores. If UI is present, circularly polarised radio emission is predicted to be emitted. We have searched for this predicted radio emission from short period binaries using the VLA and ATCA. In one epoch we find evidence for a radio source, coincident in position with the optical position of RX J0806+15. Although we cannot completely exclude that this is a chance alignment between the position of RX J0806+15 and an artifact in the data ...

2007-01-01

113

Nuclear emergencies and behavior of the people: a challenge  

International Nuclear Information System (INIS)

Full text: The IRSN has been organizing enquiries with the French population about risk and risk perception for a long time. In 2002, a collaboration between the IRSN in France and the SCK.CEN in Belgium has been set-up to simultaneously (November 2002) organise this poll in both countries. In each country, a representative sample of the population (over 1000 participants per country) has been consulted by Computer Aided Personal Interviews of about 30 minutes with the professional help of commercial companies: BVA in France and Research International in Belgium. The enquiry yields a broad spectrum of interesting data; here only the results relevant for the emergency context will be presented. One should be aware that these data were collected in a 'normal' period; important differences in behaviour may occur given a serious crisis. A first finding is that more than half of the respondents are convinced that an accident as severe as the Chernobyl disaster may happen in their country as ...

2003-10-03

114

Thermal Protection Materials Technology for NASA's Exploration Systems Mission Directorate  

Science.gov (United States)

To fulfill the President s Vision for Space Exploration - successful human and robotic missions between the Earth and other solar system bodies in order to explore their atmospheres and surfaces - NASA must reduce trip time, cost, and vehicle weight so that payload and scientific experiment capabilities are maximized. As a collaboration among NASA Centers, this project will generate products that will enable greater fidelity in mission/vehicle design trade studies, support risk reduction for material selections, assist in optimization of vehicle weights, and provide the material and process templates for development of human-rated qualification and certification Thermal Protection System (TPS) plans. Missions performing aerocapture, aerobraking, or direct aeroentry rely on technologies that reduce vehicle weight by minimizing the need for propellant. These missions use the destination planet s atmosphere to slow the spacecraft. Such mission profiles induce heating ...

2005-01-01

115

The weak force and SETH: The search for Extra-Terrestrial Homochirality  

Energy Technology Data Exchange (ETDEWEB)

We propose that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality{emdash}SETH. Homochirality is probably a pre-condition for life, so a chiral influence may be required to get life started. We explain how the weak force mediated by the {ital Z}{sup 0} boson gives rise to a small parity-violating energy difference (PVED) between enantiomers, and discuss how the resulting small excess of the more stable enantiomer may be amplified to homochirality. Titan and comets are good places to test for emerging pre-biotic homochirality, while on Mars there may be traces of homochirality as a relic of extinct life. Our calculations of the PVED show that the natural L-amino acids are indeed more stable than their enantiomers, as are several key D-sugars and right-hand helical DNA. Thiosubstituted DNA analogues show particularly large PVEDs. L-quartz is also more stable than D-quartz, and we believe that further crystal counts should be carried out ...

1996-07-01

116

The life span of the biosphere revisited  

Energy Technology Data Exchange (ETDEWEB)

A decade ago, Lovelock and Whitfield raised the question of how much longer the biosphere can survive on Earth. They pointed out that, despite the current fossil-fuel induced increase in the atmospheric CO[sub 2] concentration, the long-term trend should be in the opposite direction: as increased solar luminosity warms the Earth, silicate rocks should weather more readily, causing atmospheric CO[sub 2] to decrease. In their model, atmospheric CO[sub 2] falls below the critical level for C3 photosynthesis, 150 parts per million (p.p.m.), in only 100 Myr, and this is assumed to mark the demise of the biosphere as a whole. Here, this problem is re-examined using a more elaborate model that includes a more accurate treatment of the greenhouse effect of CO[sub 2] a biologically mediated weathering parameterization, and the realization that C4 photosynthesis can persist to much lower concentrations of atmospheric CO[sub 2] ([lt]10 p.p.m.). It was found that a C4-plant-based biosphere could ...

1992-12-24

117

The all-electric drill ship  

Energy Technology Data Exchange (ETDEWEB)

Oil, in various forms, has been used for thousands of years and has even been recommended as a medicinal product. Starting in the mid-19. century, however, mineral oil production became an economic, political, social and scientific gold mine. Subterranean and offshore drilling rigs have created colossal fortunes among multinationals and made certain nations extremely wealthy. Starting in the 1920's, oil companies began to explore the possibilities of undersea drilling, but it was only in 1947 that the first offshore drilling rig was set up. With three-quarters of the planet covered by water, it was inevitable that oil companies would turn to offshore drilling - especially as sub-sea oil fields may cover as much as 84 million square kilometres. Drilling rigs now go deeper than ever and are able to operate in up to 3000 meters water depth. This paper will present the technical merits of two similar all-electric drill-ships 'Pride Africa' ...

2000-07-01

118

Hot, flat and crowded. Why we need a green revolution - and how it can renew America  

International Nuclear Information System (INIS)

The author blows the whistle about what he considers as a worldwide environmental crisis. He brings a fresh outlook to the crises of destabilizing climate change and rising competition for energy - both of which could poison our world if we do not act quickly and collectively. His argument speaks to all of us who are concerned about the state of America in the global future. The author proposes that an ambitious national strategy - which he calls 'Geo-Greenism' - is not only what we need to save the planet from overheating; it is what we need to make America healthier, richer, more innovative, more productive, and more secure. He explains a new era - the Energy-Climate era - through an illuminating account of recent events. He shows how 9/11, Hurricane Katrina, and the flattening of the world by the Internet (which brought 3 billion new consumers onto the world stage) have combined to bring climate and energy issues to Main Street. But they have not gone very far ...

119

Future radioisotope power needs for missions to the solar system  

Energy Technology Data Exchange (ETDEWEB)

NASA and DOE plan a cooperative team effort with industry, government laboratories and universities to develop a near term, low cost, low power (100 watt electric class), low mass (<10 kg), advanced radioisotope space power source (ARPS) and in the process reduce the plutonium-related costs as well. The near term is focused on developing an advanced energy converter to use with the General Purpose Heat Source (GPHS). The GPHS was developed and used for the current radioisotope thermoelectric generators (RTGs). Advanced energy converter technologies are needed as a more efficient replacement for the existing thermoelectric converters so that the space radioisotope power source mass and cost can be reduced. a more advanced technology space radioisotope power system program is also planned that addresses a longer-term need. Twenty first century robotic scientific information missions to the outer planets and beyond are planned to be accomplished with ...

1997-12-31

120

First Light for MIRSI  

Science.gov (United States)

We will present the first astronomical images taken with MIRSI (Mid-InfraRed Spectrometer and Imager). First light for MIRSI is scheduled for December 2001. MIRSI is a mid-infrared camera system recently completed at Boston University that has both spectroscopic and imaging capabilities. The camera utilizes a new 320x240 Si:As IBC array developed for ground-based astronomy by Raytheon/SBRC. MIRSI offers a large field of view (1.6 arcmin x 1.2 arcmin at the IRTF with a pixel scale of 0.3 arcsec), diffraction-limited spatial resolution, complete spectral coverage over the 8-14 micron and 17-26 micron atmospheric windows for both imaging (discrete filters and CVF) and spectroscopy (10 and 20 micron grisms), and high sensitivity (expected 1-sigma point source sensitivities of 5 and 20 mJy at 10 and 20 microns, respectively, for on-source integration time of 30 seconds). This system offers the unique ability to acquire both spectra and high-resolution, multi-wavelength images of an ...

2001-12-01

 
 
 
 
121

Expectations of immortality: dam safety management into the next millennium  

Energy Technology Data Exchange (ETDEWEB)

Topics concerning the problems associated with older and aging dams are considered including: what can be done to extent the lifetime of an old dam, the decision to decommission a dam based on a value judgment that the risk of maintaining the dam is too great for society's acceptance, the possibility of change in the level of risk tolerance with time in a technological environment, traditional surveillance methods used by dam owners in the Y2K situation, and the unreality of dam immortality. Trends and means for preserving older dams for their owner's purposes are outlined, as well as their lifetime compared to that of the downstream systems they serve. Despite the fact that we live in a throwaway society, dam owners cannot just leave their dam asset when they are through with using it. Someone has to maintain the dam, or ensure that it is safely decommissioned when the owner is finished with it. On a worldwide scale the available pool of experienced dam engineers is ...

1999-07-01

122

European Space Agency announces contest to "Name the Cluster Quartet"  

Science.gov (United States)

1. Contest rules The European Space Agency (ESA) is launching a public competition to find the most suitable names for its four Cluster II space weather satellites. The quartet, which are currently known as flight models 5, 6, 7 and 8, are scheduled for launch from Baikonur Space Centre in Kazakhstan in June and July 2000. Professor Roger Bonnet, ESA Director of Science Programme, announced the competition for the first time to the European Delegations on the occasion of the Science Programme Committee (SPC) meeting held in Paris on 21-22 February 2000. The competition is open to people of all the ESA member states (*). Each entry should include a set of FOUR names (places, people, or things from history, mythology, or fiction, but NOT living persons). Contestants should also describe in a few sentences why their chosen names would be appropriate for the four Cluster II satellites. The winners will be those which are considered most suitable and relevant for the Cluster II mission. ...

2000-02-01

123

The GEOFLOW experiment missions in the Fluid Science Laboratory on ISS  

Science.gov (United States)

The GEOFLOW I experiment has been successfully performed on the International Space Sta-tion (ISS) in 2008 in the Columbus module in order to study the stability, pattern formation and transition to turbulence in a viscous incompressible fluid layer enclosed in two concentric co-rotating spheres subject to a radial temperature gradient and a radial volumetric force field. The objective of the study is the experimental investigation of large scale astrophysical and geophysical phenomena in spherical geometry stipulated by rotation, thermal convections and radial gravity fields. These systems include earth outer core or mantle convection, differen-tial rotation effects in the sun, atmosphere of gas planets as well as a variety of engineering applications. The GEOFLOW I experimental instrument consists of an experiment insert for operation in the Fluid Science Laboratory, which is part of the Columbus Module of the ISS. It was first launched in February 2008 together ...

2010-01-01

124

The Earth in energy troubles; La Planete en mal d'energie  

Energy Technology Data Exchange (ETDEWEB)

This document gathers the available presentations (articles and transparencies) given at this annual meeting, the 2007 topic of which was the technological, geopolitical, economical, environmental, societal and development stakes of energy. 1 - technological stakes - which energies for the future: new energies, illusion or solution of the future; the Lorraine region, an energy land: strategies and stakes for a sustainable development; from China to Brazil: understanding the nuclear energy revival; hydroelectric power: renewable and sustainable energy; renewable energies and environment protection: the contribution of biofuels; wind power in Germany between success and contestation; 2 - geopolitical stakes - energy levier of power: the Gulf of Guinea hydrocarbons: between development and geopolitics; the complex evaluation of resources and reserves between technology, market and geopolitics; the new Bakou-Tbilissi-Ceyhan pipeline: what impacts for Turkey and the European Union; 3 - ...

2007-07-01

125

The genesis solar-wind sample return mission  

Energy Technology Data Exchange (ETDEWEB)

The compositions of the Earth's crust and mantle, and those of the Moon and Mars, are relatively well known both isotopically and elementally. The same is true of our knowledge of the asteroid belt composition, based on meteorite analyses. Remote measurements of Venus, the Jovian atmosphere, and the outer planet moons, have provided some estimates of their compositions. The Sun constitutes a large majority, > 99%, of all the matter in the solar system. The elemental composition of the photosphere, the visible 'surface' of the Sun, is constrained by absorption lines produced by particles above the surface. Abundances for many elements are reported to the {+-}10 or 20% accuracy level. However, the abundances of other important elements, such as neon, cannot be determined in this way due to a relative lack of atomic states at low excitation energies. Additionally and most importantly, the isotopic composition of the Sun cannot be ...

2009-01-01

126

Mineralogical Data of Shocked Quartz Materials from K/T Boundary and Impact Crater  

Science.gov (United States)

Shocked quartz minerals from the Cretaceous-Tertiary (K/T) boundary and impact craters have been mainly discussed from distribution of optical directions, mean optical refractive index, and X-ray data (1). The purpose of the present study is presentation of the detailed mineralogical data of shocked quartz found in the K/T boundaries and terrestrial impact craters (2,3,4,5). X-ray powder diffraction pattern of shocked quartz aggregate reveals that all Xray peaks are split into major three peaks composed of low-density quartz (LQ), normal quartz (Q), and shocked quartz with high density (SQ). X-ray peaks of (110), (200), (201), (202), and (211) in the hexagonal cell are also split into many peaks. The X-ray intensity among LQ, Q, and SQ phases indicates that the SQ phase shows 36% to 53% in six K/T boundary samples (5). The relative X-ray intensity ratio of shocked quartz to standard rock crystal decreases into 13% to 37%, which suggests that shocked quartz materials contain major parts ...

1992-07-01

127

Science at the Theater: Hot Technology, Cool Science  

ScienceCinema

...and welcome to ...lab also known as berkeley lab my name is jeff miller and ...and a public affairs i'd like to ? ...but space is science center and ...berkeley albany high school science department and berkeley high school science department and oakland high school science ...be a q. and ...here please use and because we wanna make sure that your questions are here ...heard of also for the latest developments on science and technology ...guy we're going to be any more and more new features i hope ...and change ...thank you ? much and thank you for coming on the welcome to my world of and mayotte science journalist and what i've done for the last almost thirty years ...people about things about which there passionate and national religion tonight and ...people to explain the science and and i asking the question so what ...and ...worldwide and what it does best ? uh ...bench science and turn it into reality what do you scientists and ...uh they take scientific theory and they turn ...