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Sample records for ocean planet popular

  1. Planet Ocean

    NASA Astrophysics Data System (ADS)

    Afonso, Isabel

    2014-05-01

    A more adequate name for Planet Earth could be Planet Ocean, seeing that ocean water covers more than seventy percent of the planet's surface and plays a fundamental role in the survival of almost all living species. Actually, oceans are aqueous solutions of extraordinary importance due to its direct implications in the current living conditions of our planet and its potential role on the continuity of life as well, as long as we know how to respect the limits of its immense but finite capacities. We may therefore state that natural aqueous solutions are excellent contexts for the approach and further understanding of many important chemical concepts, whether they be of chemical equilibrium, acid-base reactions, solubility and oxidation-reduction reactions. The topic of the 2014 edition of GIFT ('Our Changing Planet') will explore some of the recent complex changes of our environment, subjects that have been lately included in Chemistry teaching programs. This is particularly relevant on high school programs, with themes such as 'Earth Atmosphere: radiation, matter and structure', 'From Atmosphere to the Ocean: solutions on Earth and to Earth', 'Spring Waters and Public Water Supply: Water acidity and alkalinity'. These are the subjects that I want to develop on my school project with my pupils. Geographically, our school is located near the sea in a region where a stream flows into the sea. Besides that, our school water comes from a borehole which shows that the quality of the water we use is of significant importance. This project will establish and implement several procedures that, supported by physical and chemical analysis, will monitor the quality of water - not only the water used in our school, but also the surrounding waters (stream and beach water). The samples will be collected in the borehole of the school, in the stream near the school and in the beach of Carcavelos. Several physical-chemical characteristics related to the quality of the water will be taken into consideration, for instance, the value of the pH, using universal indicator paper, color, through visual evaluation and the temperature with the help of a thermometer. There will be also registered some existent chemical parameters as chloride, alkalinity, total hardness (Ca2+ and Mg2+), nitrate, nitrite, ammonia and phosphate. Two methods will be used for analysis, the titration and the kit of semi-quantitative chemical analyses. This kit is composed by biocompatible substances, which means they are not harmful for the environment and can be disposed of by domestic sewage systems. The results will be subsequently analyzed bearing in mind the maximum and recommended standards values for each one of the parameters. After this, the results achieved will be discussed. I believe this project contains characteristics that will be of interest to our students, thus enabling them to participate actively and effectively develop their knowledge and enhance their scientific curiosity.

  2. The ocean planet.

    PubMed

    Hinrichsen, D

    1998-01-01

    The Blue Planet is 70% water, and all but 3% of it is salt water. Life on earth first evolved in the primordial soup of ancient seas, and though today's seas provide 99% of all living space on the planet, little is known about the world's oceans. However, the fact that the greatest threats to the integrity of our oceans come from land-based activities is becoming clear. Humankind is in the process of annihilating the coastal and ocean ecosystems and the wealth of biodiversity they harbor. Mounting population and development pressures have taken a grim toll on coastal and ocean resources. The trend arising from such growth is the chronic overexploitation of marine resources, whereby rapidly expanding coastal populations and the growth of cities have contributed to a rising tide of pollution in nearly all of the world's seas. This crisis is made worse by government inaction and a frustrating inability to enforce existing coastal and ocean management regulations. Such inability is mainly because concerned areas contain so many different types of regulations and involve so many levels of government, that rational planning and coordination of efforts are rendered impossible. Concerted efforts are needed by national governments and the international community to start preserving the ultimate source of all life on earth. PMID:12349465

  3. Ocean Planet. Interdisciplinary Marine Science Activities.

    ERIC Educational Resources Information Center

    Branca, Barbara

    The Ocean Planet is a traveling exhibition from the Smithsonian Institution designed to share with the public what recent research has revealed about the oceans and to encourage ocean conservation. This booklet of lessons and activities adapts several themes from the exhibition for use in middle and high school classrooms. Lesson plans include:…

  4. Visions of our Planet's Atmosphere, Land & Oceans

    NASA Technical Reports Server (NTRS)

    Hasler, Arthur F.

    2002-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to South Africa, Cape Town and Johannesburg using NASA Terra MODIS data, Landsat data and 1m IKONOS "Spy Satellite" data. Zoom in to any place South Africa using Earth Viewer 3D from Keyhole Inc. and Landsat data at 30 m resolution. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes & "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we present science to the public. See dust storms and flooding in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers of Newsweek, TIME, National Geographic, Popular Science & on National & International Network TV. New computer software tools allow us to roam & zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the north and south polar ice packs and with icebergs on the coasts of Greenland and off the coast of Antarctica. Spectacular new visualizations of the global land, atmosphere & oceans are shown. Listen to the pulse of our planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and biomass burning of the Earth at night observed by the "night-vision" DMSP military satellite. The presentation will be made using the latest HDTV and video projection technology that is now done from a laptop computer through an entirely digital path.

  5. Hydrothermal systems in small ocean planets.

    PubMed

    Vance, Steve; Harnmeijer, Jelte; Kimura, Jun; Hussmann, Hauke; Demartin, Brian; Brown, J Michael

    2007-12-01

    We examine means for driving hydrothermal activity in extraterrestrial oceans on planets and satellites of less than one Earth mass, with implications for sustaining a low level of biological activity over geological timescales. Assuming ocean planets have olivine-dominated lithospheres, a model for cooling-induced thermal cracking shows how variation in planet size and internal thermal energy may drive variation in the dominant type of hydrothermal system-for example, high or low temperature system or chemically driven system. As radiogenic heating diminishes over time, progressive exposure of new rock continues to the current epoch. Where fluid-rock interactions propagate slowly into a deep brittle layer, thermal energy from serpentinization may be the primary cause of hydrothermal activity in small ocean planets. We show that the time-varying hydrostatic head of a tidally forced ice shell may drive hydrothermal fluid flow through the seafloor, which can generate moderate but potentially important heat through viscous interaction with the matrix of porous seafloor rock. Considering all presently known potential ocean planets-Mars, a number of icy satellites, Pluto, and other trans-neptunian objects-and applying Earth-like material properties and cooling rates, we find depths of circulation are more than an order of magnitude greater than in Earth. In Europa and Enceladus, tidal flexing may drive hydrothermal circulation and, in Europa, may generate heat on the same order as present-day radiogenic heat flux at Earth's surface. In all objects, progressive serpentinization generates heat on a globally averaged basis at a fraction of a percent of present-day radiogenic heating and hydrogen is produced at rates between 10(9) and 10(10) molecules cm(2) s(1). PMID:18163874

  6. The unstable CO2 feedback cycle on ocean planets

    NASA Astrophysics Data System (ADS)

    Kitzmann, Daniel; Alibert, Yann; Godolt, Mareike; Grenfell, John Lee; Heng, Kevin; Patzer, Beate; Rauer, Heike; Stracke, Barbara; von Paris, Philip

    2015-12-01

    Ocean planets are volatile rich planets, not present in our Solar System, which are dominated by deep, global oceans. Theoretical considerations and planet formation modeling studies suggest that extrasolar ocean planets should be a very common type of planet. One might therefore expect that low-mass ocean planets would be ideal candidates when searching for habitable exoplanets, since water is considered to be an essential requirement for life. However, a very large global ocean can also strongly influence the climate.The high pressure at the oceans bottom results in the formation of high-pressure water ice, separating the planetary crust from the liquid ocean and, thus, also from the atmosphere. In our study we, therefore, focus on the CO2 cycle between the atmosphere and the ocean which determines the atmospheric CO2 content. The atmospheric amount of CO2 is a fundamental quantity for assessing the potential habitability of the planet's surface because of its strong greenhouse effect, which determines the planetary surface temperature to a large degree.In contrast to the stabilising carbonate-silicate cycle regulating the long-term CO2 inventory of the Earth atmosphere, we find that the CO2 cycle on ocean planets is positive and has strong destabilising effects on the planetary climate. By using a chemistry model for oceanic CO2 dissolution and an atmospheric model for exoplanets, we show that the CO2 feedback cycle is severely limiting the potential habitability of ocean planets.

  7. The unstable CO2 feedback cycle on ocean planets

    NASA Astrophysics Data System (ADS)

    Kitzmann, D.; Alibert, Y.; Godolt, M.; Grenfell, J. L.; Heng, K.; Patzer, A. B. C.; Rauer, H.; Stracke, B.; von Paris, P.

    2015-10-01

    Ocean planets are volatile-rich planets, not present in our Solar system, which are thought to be dominated by deep, global oceans. This results in the formation of high-pressure water ice, separating the planetary crust from the liquid ocean and, thus, also from the atmosphere. Therefore, instead of a carbonate-silicate cycle like on the Earth, the atmospheric carbon dioxide concentration is governed by the capability of the ocean to dissolve carbon dioxide (CO2). In our study, we focus on the CO2 cycle between the atmosphere and the ocean which determines the atmospheric CO2 content. The atmospheric amount of CO2 is a fundamental quantity for assessing the potential habitability of the planet's surface because of its strong greenhouse effect, which determines the planetary surface temperature to a large degree. In contrast to the stabilizing carbonate-silicate cycle regulating the long-term CO2 inventory of the Earth atmosphere, we find that the CO2 cycle feedback on ocean planets is negative and has strong destabilizing effects on the planetary climate. By using a chemistry model for oceanic CO2 dissolution and an atmospheric model for exoplanets, we show that the CO2 feedback cycle can severely limit the extension of the habitable zone for ocean planets.

  8. Persistence of oceans on Earth-like planets

    NASA Astrophysics Data System (ADS)

    Schaefer, Laura; Sasselov, Dimitar D.

    2015-01-01

    The habitable zone is an orbital region around a star in which an Earth-like planet can maintain liquid water on its surface given a variety of atmospheric compositions. However, the abundance of water on the Earth's surface is not controlled by the atmosphere, but rather by the deep water/silicate cycle. On the Earth, volcanic outgassing of water from the mantle is balanced by loss of water to the mantle through subduction of water-rich oceanic seafloor. Much of this water is released immediately back to the surface through shallow, water-induced volcanism. However, a small but significant fraction of the water can be transported to deeper levels of the mantle. Mantle convection has therefore played an important role in controlling the size of Earth's surface oceans over the planet's lifetime.The deep water cycle of Earth has been studied with parameterized convection models incorporating a water-dependent viscosity. The abundance of water in the mantle, which lowers the convective viscosity, evolves along with the mantle temperature. Here we present results from a parameterized convection model extended to high pressures to study the deep water cycles of super-Earths. Assuming compositions similar to the Earth, our models indicate that ocean formation will be delayed on 5 MEarth planets by ~1 Gyr after planet formation. Although ocean mass on these planets increases with time, the oceans remain much shallower than for smaller planets, consistent with previous studies. Intermediate mass planets (2-4 MEarth) have immediate, but gradual outgassing and persistent oceans. Small terrestrial planets (≤ 1 MEarth) have rapid initial outgassing, but will gradually lose a significant fraction of their surface oceans due to mantle sequestration over their lifetimes.

  9. Formation of Early Water Oceans on Rocky Planets

    NASA Astrophysics Data System (ADS)

    Elkins-Tanton, L. T.

    2011-12-01

    Terrestrial planets, with silicate mantles and metallic cores, are likely to obtain water and carbon compounds during accretion. Terrestrial planets are expected to accrete from differentiated planetary embryos and planetesimals; achondritic meteorites, therefore, may be a reasonable analog for the volatile contents of the materials that built the Earth and other terrestrial planets. Achondritic meteorites contain small but often non-zero water contents, from a few parts per million to around 3 wt%. Water is therefore delivered to the planet during primary accretion as well as during late accretion (sometimes known as the late veneer). Some water content is preserved even during very large accretionary impacts. Volatiles, including water, participate in all stages in a planet's evolution: Core formation (through oxidation/reduction and partitioning), mantle solidification and silicate differentiation (through partitioning and degassing), the onset of plate tectonics (through viscosity reduction in the silicates), and atmosphere and ocean formation. Here I present models that show the greatest fraction of a planet's initial volatile budget is degassed into the atmosphere during the end of magma ocean solidification, leaving only a small fraction of the original volatiles to be released into the atmosphere through later volcanism. The fraction of volatiles remaining in the silicate mantle, however, is sufficient to reduce the viscosity of the upper mantle and encourage plate tectonics, as well as lower the solidus for subsequent melting and volcanism. Rocky planets that accrete with as little as 0.01 mass% water or lower produce a massive supercritical fluid and steam atmosphere that collapses into a water ocean upon cooling. The low water contents required for this process indicate that rocky super-Earth exoplanets may be expected to commonly produce water oceans through collapse of their atmosphere, and models indicate that an Earth-sized planet would cool to clement conditions and form a water ocean in just a few to tens of millions of years.

  10. Formation of early water oceans on rocky planets

    NASA Astrophysics Data System (ADS)

    Elkins-Tanton, Linda T.

    2011-04-01

    Terrestrial planets, with silicate mantles and metallic cores, are likely to obtain water and carbon compounds during accretion. Here I examine the conditions that allow early formation of a surface water ocean (simultaneous with cooling to clement surface conditions), and the timeline of degassing the planetary interior into the atmosphere. The greatest fraction of a planet's initial volatile budget is degassed into the atmosphere during the end of magma ocean solidification, leaving only a small fraction of the original volatiles to be released into the atmosphere through later volcanism. Rocky planets that accrete with water in their bulk mantle have two mechanisms for producing an early water ocean: First, if they accrete with at least 1 to 3 mass% of water in their bulk composition, liquid water may be extruded onto the planetary surface at the end of magma ocean solidification. Second, at initial water contents as low as 0.01 mass% or lower, during solidification a massive supercritical fluid and steam atmosphere is produced that collapses into a water ocean upon cooling. The low water contents required for this process indicate that rocky super-Earth exoplanets may be expected to commonly produce water oceans within tens to hundreds of millions of years of their last major accretionary impact, through collapse of their atmosphere.

  11. Applications of Ocean Acoustic Monitoring to Understanding Our Planet

    SciTech Connect

    Tolstoy, Maya

    2005-10-26

    The ocean covers two-thirds of the surface of Earth, and hides long chains of seafloor volcanoes, bizarre and magnificent life forms, and many dynamic geological processes. Shrouded in darkness, much of what happens deep in the ocean is unknown to us. But sound can tell us a great deal about what is going on in the ocean. Changes in the physical properties of seawater with depth allow relatively quiet sounds to travel great distances without loosing much energy. In this way we are able to record many noises that occur within or on the boundary of the ocean, giving us insight into geological, biological and man-made activities in the ocean. One of the most interesting noises to a geophysicist is the sound of mid-ocean ridge volcanic eruptions. These eruptions are forming new surface for our planet and helping create an extraordinary seafloor ecosystem. Examples of sounds heard and some of their implications will be presented.

  12. DETECTING OCEANS ON EXTRASOLAR PLANETS USING THE GLINT EFFECT

    SciTech Connect

    Robinson, Tyler D.; Meadows, Victoria S.; Crisp, David

    2010-09-20

    Glint, the specular reflection of sunlight off Earth's oceans, may reveal the presence of oceans on an extrasolar planet. As an Earth-like planet nears crescent phases, the size of the ocean glint spot increases relative to the fraction of the illuminated disk, while the reflectivity of this spot increases. Both effects change the planet's visible reflectivity as a function of phase. However, strong forward scattering of radiation by clouds can also produce increases in a planet's reflectivity as it approaches crescent phases, and surface glint can be obscured by Rayleigh scattering and atmospheric absorption. Here, we explore the detectability of glint in the presence of an atmosphere and realistic phase-dependent scattering from oceans and clouds. We use the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model to simulate Earth's broadband visible brightness and reflectivity over an orbit. Our validated simulations successfully reproduce phase-dependent Earthshine observations. We find that the glinting Earth can be as much as 100% brighter at crescent phases than simulations that do not include glint, and that the effect is dependent on both orbital inclination and wavelength, where the latter dependence is caused by Rayleigh scattering limiting sensitivity to the surface. We show that this phenomenon may be observable using the James Webb Space Telescope paired with an external occulter.

  13. Mission to Planet Earth. The living ocean: Observing ocean color from space

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Measurements of ocean color are part of NASA's Mission to Planet Earth, which will assess how the global environment is changing. Using the unique perspective available from space, NASA will observe, monitor, and study large-scale environmental processes, focusing on quantifying climate change. NASA will distribute the results of these studies to researchers worldwide to furnish a basis for informed decisions on environmental protection and economic policy. This information packet includes discussion on the reasons for measuring ocean color, the carbon cycle and ocean color, priorities for global climate research, and SeWiFS (sea-viewing wide field-of-view sensor) global ocean color measurements.

  14. Europa, tidally heated oceans, and habitable zones around giant planets.

    PubMed

    Reynolds, R T; McKay, C P; Kasting, J F

    1987-01-01

    Tidal dissipation in the satellites of a giant planet may provide sufficient heating to maintain an environment favorable to life on the satellite surface or just below a thin ice layer. In our own solar system, Europa, one of the Galilean satellites of Jupiter, could have a liquid ocean which may occasionally receive sunlight through cracks in the overlying ice shell. In such case, sufficient solar energy could reach liquid water that organisms similar to those found under Antarctic ice could grow. In other solar systems, larger satellites with more significant heat flow could represent environments that are stable over an order of Aeons and in which life could perhaps evolve. We define a zone around a giant planet in which such satellites could exist as a tidally-heated habitable zone. This zone can be compared to the habitable zone which results from heating due to the radiation of a central star. In our solar system, this radiatively-heated habitable zone contains the Earth. PMID:11538217

  15. Visions of Our Planet's Atmosphere, Land & Oceans - ETheater Presentation

    NASA Technical Reports Server (NTRS)

    Hasler, F.

    2000-01-01

    The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes & tornadic thunderstorms. See the latest spectacular images from NASA and NOAA remote sensing missions like GOES, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. See visualizations featured on covers of ma'gazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using 1 m resolution spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUS, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.

  16. Emergence of two types of terrestrial planet on solidification of magma ocean.

    PubMed

    Hamano, Keiko; Abe, Yutaka; Genda, Hidenori

    2013-05-30

    Understanding the origins of the diversity in terrestrial planets is a fundamental goal in Earth and planetary sciences. In the Solar System, Venus has a similar size and bulk composition to those of Earth, but it lacks water. Because a richer variety of exoplanets is expected to be discovered, prediction of their atmospheres and surface environments requires a general framework for planetary evolution. Here we show that terrestrial planets can be divided into two distinct types on the basis of their evolutionary history during solidification from the initially hot molten state expected from the standard formation model. Even if, apart from their orbits, they were identical just after formation, the solidified planets can have different characteristics. A type I planet, which is formed beyond a certain critical distance from the host star, solidifies within several million years. If the planet acquires water during formation, most of this water is retained and forms the earliest oceans. In contrast, on a type II planet, which is formed inside the critical distance, a magma ocean can be sustained for longer, even with a larger initial amount of water. Its duration could be as long as 100 million years if the planet is formed together with a mass of water comparable to the total inventory of the modern Earth. Hydrodynamic escape desiccates type II planets during the slow solidification process. Although Earth is categorized as type I, it is not clear which type Venus is because its orbital distance is close to the critical distance. However, because the dryness of the surface and mantle predicted for type II planets is consistent with the characteristics of Venus, it may be representative of type II planets. Also, future observations may have a chance to detect not only terrestrial exoplanets covered with water ocean but also those covered with magma ocean around a young star. PMID:23719462

  17. On the Origins of Atmospheres and Oceans on Rocky Planets (Invited)

    NASA Astrophysics Data System (ADS)

    Elkins-Tanton, L. T.

    2013-12-01

    The earliest atmospheres of terrestrial planets are likely a combination of degassing of their own material with captured nebular gases. Degassing occurs during giant accretionary impacts and solidification of impact-induced melt. Observations from our solar system indicate that accreting materials have sufficient volatiles to build dense atmospheres and oceans and also to populate the planetary interior with volatiles for later degassing through volcanism. Many questions remain about the efficiency of degassing magma oceans, the degree to which later impacts remove atmospheres and oceans, and the speed at which cooling steam atmospheres collapse into oceans and thus elude stripping by the energetic young star. Atmospheric stripping is an especially current topic: How much distance from the star, planetary mass, and the possibility of a magnetic dynamo protect the early atmosphere from stripping? Nonetheless, compositional data from meteorites and comets indicate that our planets obtained their water from rocky accreting materials, and observations from missions indicate that accretionary impacts do not entirely remove volatiles. The low initial water contents required to produce oceans (as little as a few hundred ppm water) indicate that rocky planets may be generally expected to produce water oceans through degassing, and that an Earth-sized planet would cool to clement conditions in just a few to tens of millions of years. Thus, rocky planets are likely to accrete with sufficient water to form early oceans. Though this first atmosphere is subsequently changed and depleted past recognition, it may also have played an important role in determining the planet's surface and habitability. Later atmospheres and oceans will inevitably comprise some combination of the volatiles degassed during accretion and cooling, volatiles delivered during the tail of accretion, and volatiles released from later volcanism.

  18. Moments of probable seas: statistical dynamics of Planet Ocean

    NASA Astrophysics Data System (ADS)

    Holloway, Greg

    The ocean is too big. From the scale of planetary radius to scales of turbulent microstructure, the range of length scales is 109. Likewise for time scales. Classical geophysical fluid dynamics does not have an apparatus for dealing with such complexity, while `brute force' computing on the most powerful supercomputers, extant or presently foreseen, barely scratches this complexity. Yet the everywhere-swirling-churning ocean interacts unpredictably in climate history and climate future - against which we attempt to devise planetary stewardship. Can we better take into account the unpredictability of oceans to improve upon present ocean/climate forecasting? What to do? First, recognize that our goal is to comprehend probabilities of possible oceans. Questions we would ask are posed as moments (expectations). Then the dynamical goal is clear: we seek equations of motion of moments of probable oceans. Classical fluid mechanics offers part of the answer but fails to recognize statistical dynamical aspects (missing the arrow of time as past==>future). At probabilities of oceans, the missing physics emerges: moments are forced by gradients of entropy with respect to moments. Time regains its arrow, and first (simplest) approximations to entropy-gradient forces enhance the fidelity of ocean theories and practical models.

  19. Hypothetical Inverted Critical Zones for Subsurface Biospheres on Desert Planets and Icy Ocean Worlds

    NASA Astrophysics Data System (ADS)

    Boston, P. J.

    2015-10-01

    Earth as a model for cave habitable real-estate does not encompass other possibilities including desert planets like Mars, or icy ocean worlds viewed as planetary-scale water-filled caves in water ice bedrock which will have inverted Critical Zones.

  20. It's Only a Little Planet: A Primer for Ocean Studies.

    ERIC Educational Resources Information Center

    Meyland, Sarah J.

    Developed as part of the Day on the Bay Cruise Program, funded by the National Sea Grant Program, this learner's manual outlines ocean studies conducted on a seven-hour cruise of the Galveston Bay area. A description of the geology and human use of Galveston Bay follows a general introduction to coastal and estuarine ecology. Line drawings

  1. It's Only a Little Planet: A Primer for Ocean Studies.

    ERIC Educational Resources Information Center

    Meyland, Sarah J.

    Developed as part of the Day on the Bay Cruise Program, funded by the National Sea Grant Program, this learner's manual outlines ocean studies conducted on a seven-hour cruise of the Galveston Bay area. A description of the geology and human use of Galveston Bay follows a general introduction to coastal and estuarine ecology. Line drawings…

  2. The Blue Planet: Seas & Oceans. Young Discovery Library Series.

    ERIC Educational Resources Information Center

    de Beauregard, Diane Costa

    This book is written for children ages 5 through 10. Part of a series designed to develop their curiosity, facinate them and educate them, this volume explores the physical and environmental characteristics of the world's oceans. Topics are: (1) human exploration; (2) the food chain; (3) coral reefs; (4) currents and tides; (5) waves; (6)

  3. The Blue Planet: Seas & Oceans. Young Discovery Library Series.

    ERIC Educational Resources Information Center

    de Beauregard, Diane Costa

    This book is written for children ages 5 through 10. Part of a series designed to develop their curiosity, facinate them and educate them, this volume explores the physical and environmental characteristics of the world's oceans. Topics are: (1) human exploration; (2) the food chain; (3) coral reefs; (4) currents and tides; (5) waves; (6)…

  4. Oceanic Communities in a Changing Planet - The Tara Oceans Project (GSC8 Meeting)

    SciTech Connect

    Raes, Jeroen

    2009-09-09

    The Genomic Standards Consortium was formed in September 2005. It is an international, open-membership working body which promotes standardization in the description of genomes and the exchange and integration of genomic data. The 2009 meeting was an activity of a five-year funding "Research Coordination Network" from the National Science Foundation and was organized held at the DOE Joint Genome Institute with organizational support provided by the JGI and by the University of California - San Diego. Jeroen Raes of the University of Brussels discusses the Tara-Oceans expedition at the Genomic Standards Consortium's 8th meeting at the DOE JGI in Walnut Creek, Calif. on Sept. 9, 2009

  5. Oceanic Communities in a Changing Planet - The Tara Oceans Project (GSC8 Meeting)

    ScienceCinema

    Raes, Jeroen [University of Brussels

    2011-04-28

    The Genomic Standards Consortium was formed in September 2005. It is an international, open-membership working body which promotes standardization in the description of genomes and the exchange and integration of genomic data. The 2009 meeting was an activity of a five-year funding "Research Coordination Network" from the National Science Foundation and was organized held at the DOE Joint Genome Institute with organizational support provided by the JGI and by the University of California - San Diego. Jeroen Raes of the University of Brussels discusses the Tara-Oceans expedition at the Genomic Standards Consortium's 8th meeting at the DOE JGI in Walnut Creek, Calif. on Sept. 9, 2009

  6. Influence of initial CO2 content on a planet surface conditions at the end of the magma ocean phase

    NASA Astrophysics Data System (ADS)

    Salvador, A.; Massol, H.; Davaille, A.; Marcq, E.; Sarda, P.; Chassefière, E.

    2015-10-01

    The earliest compositional differentiation of the terrestrial planets, the formation of their outgassed atmospheres, and the existence of condensed water oceans over their solid mantles, are conditioned by magma ocean (MO) formation and solidification. Recent studies have suggested that depending on the planet initial water content and its orbital distance to the sun, two types of conditions, with (I) or without (II) water ocean, can prevail at the end of the MO phase. We use a coupled interior-atmosphere model of MO thermal evolution to go further and study systematically the influence of the planet initial CO2 content on the resulting surface conditions (temperature, volatiles, condensed water) at the end of the MO phase. The position of the boundary between the two regimes is shown to depend also on the initial CO2 content.

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

    NASA Technical Reports Server (NTRS)

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

    2015-01-01

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

  8. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA E-Theater 2003

    NASA Technical Reports Server (NTRS)

    Hasler, Fritz

    2003-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations from space in a spectacular way. Fly in from outer space to the conference location as well as the site of the 2002 Olympic Winter Games using data from NASA satellites and the IKONOS "Spy Satellite". See HDTV movie Destination Earth 2002 incorporating the Olympic Zooms, NBC footage of the 2002 Olympics, the shuttle, & the best NASA/NOAA Earth science visualizations. See the latest US and international global satellite weather movies including hurricanes, typhoons & "tornadoes". See the latest visualizations from NASA/NOAA and International remote sensing missions like Terra, Aqua, GOES, GMS, SeaWiFS, & Landsat. Feel the pulse of our planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP satellite. The presentation will be made using the latest HDTV and video projection technology by: Dr. Fritz Hasler NASA/Goddard Space Flight Center

  9. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA E-Theater 2003

    NASA Technical Reports Server (NTRS)

    Hasler, Fritz

    2003-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations from space in a spectacular way. Fly in from outer space to the conference location as well as the site of the 2002 Olympic Winter Games using data from NASA satellites and the IKONOS "Spy Satellite". See HDTV movie Destination Earth 2002 incorporating the Olympic Zooms, NBC footage of the 2002 Olympics, the shuttle, & the best NASA/NOAA Earth science visualizations. See the latest US and international global satellite weather movies including hurricanes, typhoons & "tornadoes". See the latest visualizations from NASA/NOAA and International remote sensing missions like Terra, Aqua, GOES, GMS , SeaWiFS, & Landsat. Feel the pulse of our planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the the "night-vision" DMSP satellite. The presentation will be made using the latest HDTV and video projection technology by: Dr. Fritz Hasler NASA/Goddard Space Flight Center

  10. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA E-Theater 2003

    NASA Technical Reports Server (NTRS)

    Hasler, Fritz

    2003-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations from space in a spectacular way. Fly in from outer space to the conference location as well as the site of the 2002 Olympic Winter Games using data from NASA satellites and the IKONOS 'Spy Satellite". See HDTV movie Destination Earth 2002 incorporating the Olympic Zooms, NBC footage of the 2002 Olympics, the shuttle, & the best NASA/NOAA Earth science visualizations. See the latest US and international global satellite weather movies including hurricanes, typhoons & "tornadoes". See the latest visualizations from NASA/NOAA and International remote sensing missions like Terra, Aqua, GOES, GMS, SeaWiFS, & Landsat. Feel the pulse of OUT planet. See how land vegetation, ocean plankton, clouds and temperatures respond to the sun & seasons. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP satellite. The presentation will be made using the latest HDTV and video projection technology by: Dr. Fritz Hasler NASA/Goddard Space Flight Center.

  11. A Presentation of Spectacular Visualizations. Visions of Our Planet's Atmosphere, Land and Oceans: ETheater Presentation

    NASA Technical Reports Server (NTRS)

    Hasler, Fritz; Pierce, Hal; Einaudi, Franco (Technical Monitor)

    2000-01-01

    The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes & tornadic thunderstorms. See the latest spectacular images from NASA and NOAA remote sensing missions like GOES, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. See visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using 1 m resolution spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See ocean vortices and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.

  12. Visions of Our Planet's Atmosphere, Land and Oceans: Electronic-Theater 2000

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.

    2000-01-01

    The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the Delaware Bay and Philadelphia area. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer tropical cyclones & tornadic thunderstorms. See the latest spectacular images from NASA, NOAA & UMETSAT remote sensing missions like GOES, Meteosat, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. see visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including Landsat tours of the US, and Africa with drill downs of major global cities using 1 m resolution commercialized spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. see ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across a super sized panoramic screen.

  13. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA Electronic Theater 2002

    NASA Technical Reports Server (NTRS)

    Haser, Fritz; Starr, David (Technical Monitor)

    2002-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the 2002 Winter Olympic Stadium Site of the Olympic Opening and Closing Ceremonies in Salt Lake City. Fly in and through Olympic Alpine Venues using 1 m IKONOS "Spy Satellite" data. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes and "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including new 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we communicate science. (In cooperation with the American Museum of Natural History in NYC) See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers of Newsweek, TIME, National Geographic, Popular Science and on National and International Network TV. New computer software tools allow us to roam and zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds. data. Spectacular new visualizations of the global atmosphere and oceans are shown. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP military satellite.

  14. Visions of Our Planet's Atmosphere, Land and Oceans Electronic-Theater 2001

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    The NASA/NOAA/AMS Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Fredericton New Brunswick. Drop in on the Kennedy Space Center and Park City Utah, site of the 2002 Olympics using 1 m IKONOS "Spy Satellite" data. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and International global satellite weather movies including hurricanes & tornadoes. See the latest spectacular images from NASA/NOAA and Canadian remote sensing missions like Terra GOES, TRMM, SeaWiFS, Landsat 7, and Radarsat that are visualized & explained. See how High Definition Television (HDTV) is revolutionizing the way we communicate science in cooperation with the American Museum of Natural History in NYC. See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on Newsweek, TIME, National Geographic, Popular Science covers & National & International Network TV. New visualization tools allow us to roam & zoom through massive global images eg Landsat tours of the US, Africa, & New Zealand showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds data. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny plankton and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Onyx II Graphics Supercomputer with four CPUs, 8 Gigabytes of RAM and Terabyte of disk. With multiple projectors on a giant screen. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP military satellite.

  15. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA Electronic Theater 2002

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Starr, David (Technical Monitor)

    2001-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the Olympic Medals Plaza, the new Gateway Center, and the University of Utah Stadium Site of the Olympic Opening and Closing Ceremonies in Salt Lake City. Fly in and through the Park City, and Snow Basin sites of the 2002 Winter Olympic Alpine Venues using 1 m IKONOS "Spy Satellite" data. See the four seasons of the Wasatch Front as observed by Landsat 7 at 15m resolution and watch the trees turn color in the Fall, snow come and go in the mountains and the reservoirs freeze and melt. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes & "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including new 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we communicate science. (In cooperation with the American Museum of Natural History in NYC) See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers of Newsweek, TIME, National Geographic, Popular Science & on National & International Network TV. New computer software tools allow us to roam & zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds data. Spectacular new visualizations of the global atmosphere & oceans are shown. See vortexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "night-vision" DMSP military satellite. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with two CPUs, 4 Gigabytes of RAM and 0.5 Terabyte of disk using two projectors across a super sized panoramic 48 foot screen. In addition new HDTV technology will be demonstrated from a portable computer server.

  16. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA Electronic Theater 2002

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Starr, David (Technical Monitor)

    2002-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the Olympic Medals Plaza, the new Gateway Center, and the University of Utah Stadium Site of the Olympic Opening and Closing Ceremonies in Salt Lake City. Fly in and through the Park City, and Snow Basin sites of the 2002 Winter Olympic Alpine Venues using 1 m IKONOS "Spy Satellite" data. See the four seasons of the Wasatch Front as observed by Landsat 7 at 15m resolution and watch the trees turn color in the Fall, snow come and go in the mountains and the reservoirs freeze and melt. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies Including hurricanes & "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including new 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we communicate science. (In cooperation with the American Museum of Natural History in NYC) See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers Of Newsweek, TIME, National Geographic, Popular Science & on National & International Network TV. New computer software. tools allow us to roam & zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds data. Spectacular new visualizations of the global atmosphere & oceans are shown. See vertexes and currents in the global oceans that bring up the nutrients to feed tin) algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. See the city lights, fishing fleets, gas flares and biomass burning of the Earth at night observed by the "night-vision" DMSP military satellite. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with two CPUs, 4 Gigabytes of RAM and 0.5 Terabyte of disk using two projectors across a super sized panoramic 48 foot screen. In addition new HDTV technology will be demonstrated from a portable computer server.

  17. Electronic-Theater 2001: Visions of Our Planet's Atmosphere, Land and Oceans

    NASA Technical Reports Server (NTRS)

    Hasler, Authur; Starr, David OC. (Technical Monitor)

    2001-01-01

    The NASA/NOAA/AMS Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Wisconsin, Madison and the Monona Terrace Center. Drop in on the Kennedy Space Center and Park City Utah, site of the 2002 Olympics using I m IKONOS "Spy Satellite" data. Go back to the early weather satellite images from the 1960s pioneered by UW. Scientists and see them contrasted with the latest US and International global satellite weather movies including hurricanes & tornadoes. See the latest spectacular images from NASA/NOAA remote sensing missions like Terra GOES, TRMM, SeaWiFS, Landsat 7 that are visualized & explained. See how High Definition Television (HDTV) is revolutionizing the way we communicate science in cooperation with the American Museum of Natural History in NYC. See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on Newsweek, TIME, National Geographic, Popular Science covers & National & International Network TV. New visualization tools allow us to roam & zoom through massive global images eg Landsat tours of the US, Africa, & New Zealand showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds data. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See vortices and currents in the global oceans that bring up the nutrients to feed tiny plankton and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nina/La Nina climate changes. The demonstration is interactively driven by a SGI Onyx 11 Graphics Supercomputer with four CPUs, 8 Gigabytes of RAM and Terabyte of disk. With five projectors on a giant IMAX sized 18 x 72 ft screen. See the city lights, fishing fleets, gas flares and bio-mass burning of the Earth at night observed by the "nightvision" DMSP military satellite.

  18. The Torque of the Planet: NASA Researcher Uses NCCS Computers to Probe Atmosphere-Land-Ocean Coupling

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The study of Earth science is like a giant puzzle, says Braulio Sanchez. "The more you know about the individual pieces, the easier it is to fit them together." A researcher with Goddard's Space Geodesy Branch, Sanchez has been using NCCS supercomputer and mass storage resources to show how the angular momenta of the atmosphere, the oceans, and the solid Earth are dynamically coupled. Sanchez has calculated the magnitude of atmospheric torque on the planet and has determined some of the possible effects that torque has on Earth's rotation.

  19. Atmospheres and Oceans of Rocky Planets In and Beyond the Habitable Zones of M dwarfs

    NASA Astrophysics Data System (ADS)

    Tian, Feng

    2015-12-01

    he evolution of M dwarfs during their pre-main-sequence phase causes rocky planets in and beyond the habitable zones these stars to be in the runaway and moist greenhouse states. This scenario has been studied by three groups of researchers recently (Ramirez and Kaltenegger 2014, Tian and Ida 2015, Luger and Barnes 2015), and their consensus is that massive amount of water could have been lost during this time -- early evolution of M dwarfs could have changed the water contents of rocky planets around them, which could strongly influence the habitability of rocky planets around low mass stars. It has been proposed that dense oxygen dominant atmospheres (up to 2000 bars, Luger and Barnes 2015) because of rapid water loss. Is this true? If so, what's the condition for such atmospheres to exist and can they be maintained? On the other hand, what's the likelihood for sub-Neptunes to shrink into habitable planets under such environment? In general how is the habitability of planets around M dwarfs different from those around Sun-type stars? These are the questions we will attempt to address in this work.

  20. THE ORBITAL PHASES AND SECONDARY TRANSITS OF KEPLER-10b. A PHYSICAL INTERPRETATION BASED ON THE LAVA-OCEAN PLANET MODEL

    SciTech Connect

    Rouan, D.; Deeg, H. J.; Demangeon, O.; Samuel, B.; Cavarroc, C.; Leger, A.; Fegley, B.

    2011-11-10

    The Kepler mission has made an important observation: the first detection of photons from a terrestrial planet by observing its phase curve (Kepler-10b). This opens a new field in exoplanet science: the possibility of obtaining information about the atmosphere and surface of rocky planets, objects of prime interest. In this Letter, we apply the Lava-ocean model to interpret the observed phase curve. The model, a planet without atmosphere and a surface partially made of molten rocks, has been proposed for planets of the class of CoRoT-7b, i.e., rocky planets very close to their star (at a few stellar radii). Kepler-10b is a typical member of this family. It predicts that the light from the planet has an important emission component in addition to the reflected one, even in the Kepler spectral band. Assuming an isotropical reflection of light by the planetary surface (Lambertian-like approximation), we find that a Bond albedo of {approx}50% can account for the observed amplitude of the phase curve, as opposed to a first attempt where an unusually high value was found. We propose a physical process to explain this still large value of the albedo. The overall interpretation can be tested in the future with instruments such as the James Webb Space Telescope or the Exoplanet Characterization Observatory. Our model predicts a spectral dependence that is clearly distinguishable from that of purely reflected light and from that of a planet at a uniform temperature.

  1. A Perspective of Our Planet's Atmosphere, Land, and Oceans: A View from Space

    NASA Technical Reports Server (NTRS)

    King, Michael D.; Graham, Steven M.

    2002-01-01

    A birds eye view of the Earth from afar and up close reveals the power and magnificence of the Earth and juxtaposes the simultaneous impacts and powerlessness of humankind. The NASA Electronic Theater presents Earth science observations and visualizations in true high definition (HD) format. See the latest spectacular images from NASA & NOAA remote sensing missions like GOES, TRMM, Landsat 7, QuikScat, and Terra, which will be visualized and explained in the context of global change. Marvel at visualizations of global data sets currently available from Earth orbiting satellites, including the Earth at night with its city lights, aerosols from biomass burning, and global cloud properties. See the dynamics of vegetation growth and decay over South America over 17 years, and its contrast to the North American and Africa continents. Spectacular new visualizations of the global atmosphere & oceans will be shown. See massive dust storms sweeping across Africa and across the Atlantic to the Caribbean and Amazon basin. See ocean vortexes and currents that bring up the nutrients to feed tiny phytoplankton and draw the fish, giant whales and fisher- man. See how the ocean blooms in response to these currents and El Nino/La Nina climate changes. We will illustrate these and other topics with a dynamic theater-style presentation, along with animations of satellite launch deployments and orbital mapping to highlight aspects of Earth observations from space.

  2. A Perspective of Our Planet's Atmosphere, Land, and Oceans: A View from Space

    NASA Technical Reports Server (NTRS)

    King, Michael D.; Tucker, Compton

    2002-01-01

    A birds eye view of the Earth from afar and up close reveals the power and magnificence of the Earth and juxtaposes the simultaneous impacts and powerlessness of humankind. The NASA Electronic Theater presents Earth science observations and visualizations in an historical perspective. Fly in from outer space to South America with its Andes Mountains and the glaciers of Patagonia, ending up close and personal in Buenos Aires. See the latest spectacular images from NASA & NOAA remote sensing missions like GOES, TRMM, Landsat 7, QuikScat, and Terra, which will be visualized and explained in the context of global change. See visualizations of global data sets currently available from Earth orbiting satellites, including the Earth at night with its city lights, aerosols from biomass burning in South America and Africa, and global cloud properties. See the dynamics of vegetation growth and decay over South America over 17 years, and its contrast to the North American and Africa continents. New visualization tools allow us to roam & zoom through massive global mosaic images from the Himalayas to the dynamics of the Pacific Ocean that affect the climate of South and North America. New visualization tools allow us to roam & zoom through massive global mosaic images including Landsat and Terra tours of South America and Africa showing land use and land cover change from Patagonia to the Amazon Basin, including the Andes Mountains, the Pantanal, and the Bolivian highlands. Landsat flyins to Rio Di Janeiro and Buenos Aires will be shows to emphasize the capabilities of new satellite technology to visualize our natural environment. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa and across the Atlantic to the Caribbean and Amazon basin. See ocean vortexes and currents that bring up the nutrients to feed tiny phytoplankton and draw the fish, giant whales and fisherman. See how the ocean blooms in response to these currents and El Nino/La Nina climate changes. We will illustrate these and other topics with a dynamic theater-style presentation, along with animations of satellite launch deployments and orbital mapping to highlight aspects of Earth observations from space.

  3. The effects of cloud radiative forcing on an ocean-covered planet

    NASA Technical Reports Server (NTRS)

    Randall, David A.

    1990-01-01

    Cumulus anvil clouds, whose importance has been emphasized by observationalists in recent years, exert a very powerful influence on deep tropical convection by tending to radiatively destabilize the troposphere. In addition, they radiatively warm the column in which they reside. Their strong influence on the simulated climate argues for a much more refined parameterization in the General Circulation Model (GCM). For Seaworld, the atmospheric cloud radiative forcing (ACRF) has a powerful influence on such basic climate parameters as the strength of the Hadley circulation, the existence of a single narrow InterTropical Convergence Zone (ITCZ), and the precipitable water content of the atmosphere. It seems likely, however, that in the real world the surface CRF feeds back negatively to suppress moist convection and the associated cloudiness, and so tends to counteract the effects of the ACRF. Many current climate models have fixed sea surface temperatures but variable land-surface temperatures. The tropical circulations of such models may experience a position feedback due to ACRF over the oceans, and a negative or weak feedback due to surface CRF over the land. The overall effects of the CRF on the climate system can only be firmly established through much further analysis, which can benefit greatly from the use of a coupled ocean-atmospheric model.

  4. The Polar Ocean in a Warming Planet: Understanding for managing a unique resource of the Humankind

    NASA Astrophysics Data System (ADS)

    Azzolini, R.; Campus, P.; Weber, J.

    2012-04-01

    There is no doubt that changes in the Polar Regions are of great significance at the global level, such as having far-reaching effects on atmospheric and ocean circulation. Changes in ocean currents, temperature conditions, ice cover and reduction of permafrost regions are having impacts on marine and terrestrial ecosystems in the Arctic Regions of Europe and Northern Hemisphere. Human activity is putting pressure on the environment in these regions; maritime transport between Europe and Asia through the northern sea route and accessibility conditions to hidden Arctic resources as well as new technologies of exploitation will have a significant impact on the marine environment, on the living resources and on the regional social organization and needs. There are still unresolved issues related to national claims on continental shelf and sea areas that involve international law; in these respects science can provide crucial elements for supporting political agreements. Such scenarios will present new opportunities for economic activities, but also risks which will result in new demands for marine management, monitoring systems, emergency response systems, search and rescue services as well as closer international cooperation. It will also require the development of an international regime based on the improvement of the present regulations on exploration, accessibility, exploitation and liability. Dialogue and international agreements based on scientific evidences and foresight are key elements for finding solutions. On the opposite hemisphere, the ocean surrounding Antarctica plays a primary role in all global climatic processes, through the annual sea ice evolution, the circum-Antarctic circulation driving the exchange of heat between low and high latitudes and the atmospheric circulation, through the density bottom currents that affect the global Thermohaline circulation (THC), and the biogeochemical cycles that have peculiar characteristics in the icy Antarctic waters. Besides this, the marine living resources and the reservoirs of energy and bio-chemical resources (e.g. gas hydrates, bio-prospecting) have a growing strategic importance in the global economy. The Antarctic Ocean, due to its isolation and extreme climatic conditions, has always been an area of international cooperation and technological challenges in support of scientific progress. In this scenario, the rapid environmental changes and the need of humankind for new and alternative reservoirs of food and energy to be exploited play a crucial role in understanding and managing the Polar oceans. The newly emerging opportunities and associated emerging threats for Arctic people increase the number of policy areas in which EU involvement is relevant and necessary. In order to gain insight into the this complex scenario and into the needs in terms of research programmes and infrastructures, policy and education to manage it, the European Polar Board launched an initiative in Polar marine science. The ESF/EPB marine initiative is intended to focus on various aspect of the Polar marine environment and to indicate a strategy focused on innovative scientific and technological topics, capable of combining together different research capacities as well as political, economic and strategic objectives, toward goals of economic and social interest. Therefore, it is based on a wide and multidisciplinary participation.

  5. Building Planet Earth

    NASA Astrophysics Data System (ADS)

    Cattermole, Peter

    2000-03-01

    Continental plates, moving as fast as human hair grows, collide, mountains buckle, the ocean abyss sucks in the Earth's crust, and volcanos explode. Here is a story that Hollywood wished it could option: the dynamic cycle of geological destruction and renewal that has stretched across billions of years and shaped our planet in its current image. Scene by scene, this action-packed blockbuster can be experienced in Building Planet Earth. Peter Cattermole begins the story by describing a cloud of matter that surrounds a primitive Sun. Out of this the Earth was formed through compaction and internal heating to the point at which it became a stable, layered structure with a core, mantle, and crust. Using eye-catching images, artwork, and diagrams, Building Planet Earth presents this geological development and goes on to discuss what is happening to our planet now and what we can expect in the future. Cattermole covers in fascinating detail the impact of mass extinctions, global-warming, and ozone holes. The book features 241 illustrations--128 in full-color--and a number of useful appendices. For anyone who has ever wondered how this miraculous planet continues to thrive and surprise, this elegantly-written book will be an essential read. Peter Cattermole is a principal investigator with NASA's Planetary Geology and Geophysics Program. He has written several books on geology and astronomy as well as numerous articles for both scholarly and popular media, including Atlas of Venus (Cambridge University Press, 1997) and The Story of the Earth (Cambridge University Press, 1985).

  6. Take a Planet Walk

    ERIC Educational Resources Information Center

    Schuster, Dwight

    2008-01-01

    Physical models in the classroom "cannot be expected to represent the full-scale phenomenon with complete accuracy, not even in the limited set of characteristics being studied" (AAAS 1990). Therefore, by modifying a popular classroom activity called a "planet walk," teachers can explore upper elementary students' current understandings; create an

  7. Take a Planet Walk

    ERIC Educational Resources Information Center

    Schuster, Dwight

    2008-01-01

    Physical models in the classroom "cannot be expected to represent the full-scale phenomenon with complete accuracy, not even in the limited set of characteristics being studied" (AAAS 1990). Therefore, by modifying a popular classroom activity called a "planet walk," teachers can explore upper elementary students' current understandings; create an…

  8. Visions of our Planet's Atmosphere, Land and Oceans: NASA/NOAA Electronic-Theater 2002. Spectacular Visualizations of our Blue Marble

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.; Starr, David (Technical Monitor)

    2002-01-01

    Spectacular Visualizations of our Blue Marble The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the 2002 Winter Olympic Stadium Site of the Olympic Opening and Closing Ceremonies in Salt Lake City. Fly in and through Olympic Alpine Venues using 1 m IKONOS "Spy Satellite" data. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes & "tornadoes". See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including new 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained. See how High-Definition Television (HDTV) is revolutionizing the way we communicate science. (In cooperation with the American Museum of Natural History in NYC). See dust storms in Africa and smoke plumes from fires in Mexico. See visualizations featured on the covers of Newsweek, TIME, National Geographic, Popular Science & on National & International Network TV. New computer software tools allow us to roam & zoom through massive global images e.g. Landsat tours of the US, and Africa, showing desert and mountain geology as well as seasonal changes in vegetation. See animations of the polar ice packs and the motion of gigantic Antarctic Icebergs from SeaWinds data. Spectacular new visualizations of the global atmosphere & oceans are shown. See vertexes and currents in the global oceans that bring up the nutrients to feed tiny algae and draw the fish, whales and fisherman. See the how the ocean blooms in response to these currents and El Nicola Nina climate changes. See the city lights, fishing fleets, gas flares and biomass burning of the Earth at night observed by the "night-vision" DMSP military satellite.

  9. Role of the Midlatitude Oceanic Front in the Ozone-induced Climate Change in the Southern Hemisphere as Revealed in Aqua Planet Experiments

    NASA Astrophysics Data System (ADS)

    Ogawa, Fumiaki; Omrani, Nour-Eddine; Nishii, Kazuaki; Nakamura, Hisashi; Keenlyside, Noel

    2015-04-01

    The Southern Hemisphere Annular Mode (SAM) is the dominant mode of low-frequency atmospheric variability in the extratropical Southern Hemisphere, exerting substantial climatic impacts on extensive regions. A decadal trend of SAM observed in the troposphere during the late 20th century is considered to be related to the intensification of the stratospheric polar vortex induced by the ozone depletion. Known as a manifestation of meridional displacements of the eddy-driven polar-front jet (PFJ) and associated storm-track, the tropospheric SAM and its trend may be sensitive to the near-surface baroclinicity associated with the midlatitude oceanic frontal zone. In the present study, aqua-planet experiments with an atmospheric general circulation model are conducted by prescribing two different latitudinal profiles of zonally symmetric sea-surface temperature (SST) with and without frontal gradient in midlatitudes. A comparison of the tropospheric response to the assigned stratospheric ozone depletion between the two SST profiles reveals critical importance of the frontal SST gradient for translating the direct response of the stratospheric polar vortex to the ozone depletion down to the surface by enhancing the SAM variability and allowing the SAM its deep structure into the stratosphere in late spring through early summer.

  10. Popular Culture and English.

    ERIC Educational Resources Information Center

    Holbrook, Hilary Taylor

    1987-01-01

    Explores the origins and elements of popular culture--noting that English instruction and popular culture need not be mutually exclusive, and that selected materials from popular culture may serve goals of the English curriculum without compromising them. (NKA)

  11. Hazards to Planet Formation

    NASA Astrophysics Data System (ADS)

    Bally, J.

    2001-05-01

    The Orion Nebula provides a remarkable window on the first few million years in the lives of typical young stars and planetary systems. HST has demonstrated that most young stars in the Nebula are surrounded by circumstellar disks (the so-called `proplyds'). While these observations show that planet forming environments may be common, they also demonstrate that Orion's disks are being destroyed by intense UV radiation fields. `Gravel' sufficiently large to resist photo-erosion (meter scale solids or ices) may lock-up sufficient material to eventually build rocky planets. Indeed, there is evidence for large solids in some proplyds. But, the hydrogen and helium needed for the formation of giant planets will be removed. To form in Orion-like environments, giant planets must be assembled promptly prior to UV exposure. Even rocky planets may not form if the photoionized disk corona causes surviving large particles in the disk to spiral into the central star. Thus, nearby massive stars pose severe hazards to planet formation. Star counts indicate that most stars form in Orion-like environments. Only about 10% of young stars are born in shielded environments such as the Taurus or L1641 clouds where disks may escape photo-erosion. In dark clouds, the majority of stars (> 80%) form in non-hierarchal multiple star systems where close encounters with sibling stars can destroy disks and eject young planets. Thus, most stars may never develop planetary systems. These considerations indicate that extra-Solar planets may be rare, contrary to the popular view. These conclusions are consistent with the recent discoveries of extra-Solar planets around a few percent of single stars.

  12. Planet Formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Fonda, Mark (Technical Monitor)

    2002-01-01

    Modern theories of star and planet formation and of the orbital stability of planetary systems are described and used to discuss possible characteristics of undiscovered planetary systems. The most detailed models of planetary growth are based upon observations of planets and smaller bodies within our own Solar System and of young stars and their environments. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth as do terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. These models predict that rocky planets should form in orbit about most single stars. It is uncertain whether or not gas giant planet formation is common, because most protoplanetary disks may dissipate before solid planetary cores can grow large enough to gravitationally trap substantial quantities of gas. A potential hazard to planetary systems is radial decay of planetary orbits resulting from interactions with material within the disk. Planets more massive than Earth have the potential to decay the fastest, and may be able to sweep up smaller planets in their path. The implications of the giant planets found in recent radial velocity searches for the abundances of habitable planets are discussed, and the methods that are being used and planned for detecting and characterizing extrasolar planets are reviewed.

  13. Popular Culture and Curricula.

    ERIC Educational Resources Information Center

    Browne, Ray B., Ed.; Ambrosetti, Ronald J., Ed.

    The seven essays in this publication, including four read at the fall 1969 American Studies Association meeting, attempt to present both the nature of popular culture study and a guide for teachers of popular culture courses. Papers are (1) "Popular Culture: Notes toward a Definition" by Ray B. Browne; (2) "Can Popular Culture Save American…

  14. Planet Formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Young, Richard E. (Technical Monitor)

    1997-01-01

    Modern theories of star and planet formation, which are based upon observations of the Solar System and of young stars and their environments, predict that most single stars should have rocky planets in orbit about them; the frequency of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth like terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. Models for the formation of the giant planets found in recent radial velocity searches are discussed.

  15. Planet Formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Young, Richard E. (Technical Monitor)

    1998-01-01

    An overview of current theories of star and planet formation is presented. These models are based upon observations of the Solar System and of young stars and their environments. They predict that rocky planets should form around most single stars, although it is possible that in some cases such planets are lost to orbital decay within the protoplanetary disk. The frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth like terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates.

  16. Extrasolar planets.

    PubMed

    Lissauer, J J; Marcy, G W; Ida, S

    2000-11-01

    The first known extrasolar planet in orbit around a Sun-like star was discovered in 1995. This object, as well as over two dozen subsequently detected extrasolar planets, were all identified by observing periodic variations of the Doppler shift of light emitted by the stars to which they are bound. All of these extrasolar planets are more massive than Saturn is, and most are more massive than Jupiter. All orbit closer to their stars than do the giant planets in our Solar System, and most of those that do not orbit closer to their star than Mercury is to the Sun travel on highly elliptical paths. Prevailing theories of star and planet formation, which are based on observations of the Solar System and of young stars and their environments, predict that planets should form in orbit about most single stars. However, these models require some modifications to explain the properties of the observed extrasolar planetary systems. PMID:11035782

  17. Extrasolar planets

    PubMed Central

    Lissauer, Jack J.; Marcy, Geoffrey W.; Ida, Shigeru

    2000-01-01

    The first known extrasolar planet in orbit around a Sun-like star was discovered in 1995. This object, as well as over two dozen subsequently detected extrasolar planets, were all identified by observing periodic variations of the Doppler shift of light emitted by the stars to which they are bound. All of these extrasolar planets are more massive than Saturn is, and most are more massive than Jupiter. All orbit closer to their stars than do the giant planets in our Solar System, and most of those that do not orbit closer to their star than Mercury is to the Sun travel on highly elliptical paths. Prevailing theories of star and planet formation, which are based on observations of the Solar System and of young stars and their environments, predict that planets should form in orbit about most single stars. However, these models require some modifications to explain the properties of the observed extrasolar planetary systems. PMID:11035782

  18. Conditions for oceans on Earth-like planets orbiting within the habitable zone: importance of volcanic CO{sub 2} degassing

    SciTech Connect

    Kadoya, S.; Tajika, E. E-mail: tajika@astrobio.k.u-tokyo.ac.jp

    2014-08-01

    Earth-like planets in the habitable zone (HZ) have been considered to have warm climates and liquid water on their surfaces if the carbonate-silicate geochemical cycle is working as on Earth. However, it is known that even the present Earth may be globally ice-covered when the rate of CO{sub 2} degassing via volcanism becomes low. Here we discuss the climates of Earth-like planets in which the carbonate-silicate geochemical cycle is working, with focusing particularly on insolation and the CO{sub 2} degassing rate. The climate of Earth-like planets within the HZ can be classified into three climate modes (hot, warm, and snowball climate modes). We found that the conditions for the existence of liquid water should be largely restricted even when the planet is orbiting within the HZ and the carbonate-silicate geochemical cycle is working. We show that these conditions should depend strongly on the rate of CO{sub 2} degassing via volcanism. It is, therefore, suggested that thermal evolution of the planetary interiors will be a controlling factor for Earth-like planets to have liquid water on their surface.

  19. Characterizing Earth-like planets with terrestrial planet finder

    NASA Astrophysics Data System (ADS)

    Seager, Sara; Ford, E. B.; Turner, E. L.

    2002-11-01

    For the first time in human history the possibility of detecting and studying Earth-like planets is on the horizon. Terrestrial Planet Finder (TPF), with a launch date in the 2015 timeframe, is being planned by NASA to find and characterize planets in the habitable zones of nearby stars. The mission Darwin from ESA has similar goals. The motivation for both of these space missions is the detection and spectroscopic characterization of extrasolar terrestrial planet atmospheres. Of special interest are atmospheric biomarkers-such as O2, O3, H2O, CO and CH4-which are either indicative of life as we know it, essential to life, or can provide clues to a planet's habitability. A mission capable of measuring these spectral features would also obtain sufficient signal-to-noise to characterize other terrestrial planet properties. For example, physical characteristics such as temperature and planetary radius can be constrained from low-resolution spectra. In addition, planet characteristics such as weather, rotation rate, presence of large oceans or surface ice, and existence of seasons could be derived from photometric measurements of the planet's variability. We will review the potential to characterize terrestrial planets beyond their spectral signatures. We will also discuss the possibility to detect strong surface biomarkers-such as Earth's vegetation red edge near 700 nm-that are different from any known atomic or molecular signature.

  20. Extreme Planets

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This artist's concept depicts the pulsar planet system discovered by Aleksander Wolszczan in 1992. Wolszczan used the Arecibo radio telescope in Puerto Rico to find three planets - the first of any kind ever found outside our solar system - circling a pulsar called PSR B1257+12. Pulsars are rapidly rotating neutron stars, which are the collapsed cores of exploded massive stars. They spin and pulse with radiation, much like a lighthouse beacon. Here, the pulsar's twisted magnetic fields are highlighted by the blue glow.

    All three pulsar planets are shown in this picture; the farthest two from the pulsar (closest in this view) are about the size of Earth. Radiation from charged pulsar particles would probably rain down on the planets, causing their night skies to light up with auroras similar to our Northern Lights. One such aurora is illustrated on the planet at the bottom of the picture.

    Since this landmark discovery, more than 160 extrasolar planets have been observed around stars that are burning nuclear fuel. The planets spotted by Wolszczan are still the only ones around a dead star. They also might be part of a second generation of planets, the first having been destroyed when their star blew up. The Spitzer Space Telescope's discovery of a dusty disk around a pulsar might represent the beginnings of a similarly 'reborn' planetary system.

  1. Primordial Planet Formation

    NASA Astrophysics Data System (ADS)

    Schild, Rudolph E.; Gibson, Carl H.

    Recent spacecraft observations exploring solar system properties impact standard paradigms of the formation of stars, planets and comets. We stress the unexpected cloud of microscopic dust resulting from the DEEP IMPACT mission, and the existence of molten nodules in STARDUST samples. And the theory of star formation does not explain the common occurrence of binary and multiple star systems in the standard gas fragmentation scenario. No current theory of planet formation can explain the iron core of the earth, under oceans of water. These difficulties are avoided in a scenario where the planet mass objects form primordially and are today the baryonic dark matter. They have been detected in quasar microlensing and anomalous quasar radio brightening bursts. The primordial planets often concentrate together to form a star, with residual matter seen in pre-stellar accretion discs around the youngest stars. These primordial planet mass bodies were formed of hydrogen-helium, aggregated in dense clumps of a trillion at the time of plasma neutralization 380,000 years after the big bang. Most have been frozen and invisible, but are now manifesting themselves in numerous ways as sensitive modern space telescopes become operational. Their key detection signature is their thermal emission spectrum, pegged at the 13.8 degrees Kelvin triple point of hydrogen, the baryonic dark matter (Staplefeldt et al. 1999).

  2. Ocean ecology: Life in an oceanic extreme

    NASA Astrophysics Data System (ADS)

    Epping, Eric

    2013-04-01

    Scarce food supplies could hinder biological activity in the ocean's depths. However, measurements at Mariana Trench point to an unexpectedly active microbial community in the deepest seafloor setting on the planet.

  3. Planet formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    1993-01-01

    Models of planetary formation are developed using the present single example of a planetary system, supplemented by limited astrophysical observations of star-forming regions and circumstellar disks. The solar nebula theory and the planetesimal hypothesis are discussed. The latter is found to provide a viable theory of the growth of the terrestrial planets, the cores of the giant planets, and the smaller bodies present in the solar system. The formation of solid bodies of planetary size should be a common event, at least around young stars which do not have binary companions orbiting at planetary distances. Stochastic impacts of large bodies provide sufficient angular momentum to produce the obliquities of the planets. The masses and bulk compositions of the planets can be understood in a gross sense as resulting from planetary growth within a disk whose temperature and surface density decreased with distance from the growing sun.

  4. Planet Formation

    NASA Astrophysics Data System (ADS)

    Klahr, Hubert; Brandner, Wolfgang

    2011-02-01

    1. Historical notes on planet formation Bodenheimer; 2. The formation and evolution of planetary systems Bouwman et al.; 3. Destruction of protoplanetary disks by photoevaporation Richling, Hollenbach and Yorke; 4. Turbulence in protoplanetary accretion disks Klahr, Rozyczka, Dziourkevitch, Wunsch and Johansen; 5. The origin of solids in the early solar system Trieloff and Palme; 6. Experiments on planetesimal formation Wurm and Blum; 7. Dust coagulation in protoplanetary disks Henning, Dullemond, Wolf and Dominik; 8. The accretion of giant planet cores Thommes and Duncan; 9. Planetary transits: direct vision of extrasolar planets Lecavelier des Etangs and Vidal-Madjar; 10. The core accretion - gas capture model Hubickyj; 11. Properties of exoplanets Marcy, Fischer, Butler and Vogt; 12. Giant planet formation: theories meet observations Boss; 13. From hot Jupiters to hot Neptures … and below Lovis, Mayor and Udry; 14. Disk-planet interaction and migration Masset and Kley; 15. The Brown Dwarf - planet relation Bate; 16. From astronomy to astrobiology Brandner; 17. Overview and prospective Lin.

  5. The Popular Culture Explosion.

    ERIC Educational Resources Information Center

    Browne, Ray B.; Madden, David

    Popular culture is defined here as anything produced by and/or dissembled by the mass media or mass production or transportation, either directly or indirectly, and that reaches the majority of the people. This sampler from mass magazines, intended for use in the study of popular culture, includes fiction from "Playboy"; articles on cars, Johnny…

  6. Popular Music Performance Class.

    ERIC Educational Resources Information Center

    Ginocchio, John

    2001-01-01

    Discusses the creation and content of a high school course on popular music performance. Describes how the teacher decided on aspects of the course, such as student background, transcription exercises, the student report on a popular music artist, and opportunities for performance. Reflects on what the teacher learned from the experience. (CMK)

  7. Popular Chat Day Q & A

    MedlinePlus

    ... Day / Popular Chat Day Q & A Popular Chat Day Q & A Read students most popular questions about ... New Order Free Materials National Drugs & Alcohol Chat Day Chat Day Participant FAQs Popular Chat Day Q & ...

  8. Popular Chat Day Q & A

    MedlinePlus

    ... Day / Popular Chat Day Q & A Popular Chat Day Q & A Read students’ most popular questions about ... New Order Free Materials National Drugs & Alcohol Chat Day Chat Day Participant FAQs Popular Chat Day Q & ...

  9. [Extrasolar terrestrial planets and possibility of extraterrestrial life].

    PubMed

    Ida, Shigeru

    2003-12-01

    Recent development of research on extrasolar planets are reviewed. About 120 extrasolar Jupiter-mass planets have been discovered through the observation of Doppler shift in the light of their host stars that is caused by acceleration due to planet orbital motions. Although the extrasolar planets so far observed may be limited to gas giant planets and their orbits differ from those of giant planets in our Solar system (Jupiter and Saturn), the theoretically predicted probability of existence of extrasolar terrestrial planets that can have liquid water ocean on their surface is comparable to that of detectable gas giant planets. Based on the number of extrasolar gas giants detected so far, about 100 life-sustainable planets may exist within a range of 200 light years. Indirect observation of extrasolar terrestrial planets would be done with space telescopes within several years and direct one may be done within 20 years. The latter can detect biomarkers on these planets as well. PMID:15136756

  10. Binary Planets

    NASA Astrophysics Data System (ADS)

    Ryan, Keegan; Nakajima, Miki; Stevenson, David J.

    2014-11-01

    Can a bound pair of similar mass terrestrial planets exist? We are interested here in bodies with a mass ratio of ~ 3:1 or less (so Pluto/Charon or Earth/Moon do not qualify) and we do not regard the absence of any such discoveries in the Kepler data set to be significant since the tidal decay and merger of a close binary is prohibitively fast well inside of 1AU. SPH simulations of equal mass Earths were carried out to seek an answer to this question, assuming encounters that were only slightly more energetic than parabolic (zero energy). We were interested in whether the collision or near collision of two similar mass bodies would lead to a binary in which the two bodies remain largely intact, effectively a tidal capture hypothesis though with the tidal distortion being very large. Necessarily, the angular momentum of such an encounter will lead to bodies separated by only a few planetary radii if capture occurs. Consistent with previous work, mostly by Canup, we find that most impacts are disruptive, leading to a dominant mass body surrounded by a disk from which a secondary forms whose mass is small compared to the primary, hence not a binary planet by our adopted definition. However, larger impact parameter kissing collisions were found to produce binaries because the dissipation upon first encounter was sufficient to provide a bound orbit that was then rung down by tides to an end state where the planets are only a few planetary radii apart. The long computational times for these simulation make it difficult to fully map the phase space of encounters for which this outcome is likely but the indications are that the probability is not vanishingly small and since planetary encounters are a plausible part of planet formation, we expect binary planets to exist and be a non-negligible fraction of the larger orbital radius exoplanets awaiting discovery.

  11. Mission to planet earth

    SciTech Connect

    Baker, D.J.

    1988-07-01

    Plans for environmental monitoring using remote-sensing satellites in the era of the International Space Station are reviewed. The role of international cooperation is stressed, considering the present Landsat, SPOT, and Marine Observation Satellite programs; ERS-1 and Topex/Poseidon; and plans for the Italian Lageos-2, the Indian Remote Sensing Satellite, and the Japanese Advanced Earth Observation Satellite. The NASA Mission to Planet Earth proposal calls for four polar-orbit and five GEO platforms (five NASA, two ESA, and two NASDA), to be in place by the year 2000, as well as dedicated spacecraft of the Earth System Explorer series in the 1990s. Payloads will monitor the geomagnetic field, atmospheric temperature and water vapor, O3 and aerosols, outgoing radiation, precipitation, sea-surface temperature, sea ice, ocean chlorophyll, surface winds, wave height, ocean circulation, snow cover, land use, vegetation, crops, volcanic activity, and the hydrologic cycle.

  12. A Planet Detection Tutorial and Simulator

    NASA Astrophysics Data System (ADS)

    Koch, D.

    2000-12-01

    Detection of extra-solar planets has been a very popular topic with the general public for years. Considerable media coverage of recent detections (currently at about 50) has only heightened the interest in the topic. School children are particularly interested in learning about recent astronomical discoveries. Scientists have the knowledge and responsibility to present this information in both an understandable and interesting format. Most classrooms and homes are now connected to the internet, which can be utilized to provide more than a traditional "flat" presentation. An interactive software package on planet detection has been developed. The major topics include: "1996 - The Break Through Year In Planet Detection"; "What Determines If A Planet Is Habitable?"; "How Can We Find Other Planets (Search Methods)"; "All About the Kepler Mission: How To Find Terrestrial Planets"; and "A Planet Detection Simulator". Using the simulator, the student records simulated observations and then analyzes and interprets the data within the program. One can determine the orbit and planet size, the planet's temperature and surface gravity, and finally determine if the planet is habitable. Originally developed for the Macintosh, a web based browser version is being developed.

  13. A Planet Detection Tutorial and Simulator

    NASA Technical Reports Server (NTRS)

    Knoch, David; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    Detection of extra-solar planets has been a very popular topic with the general public for years. Considerable media coverage of recent detections (currently at about 50) has only heightened the interest in the topic. School children are particularly interested in learning about recent astronomical discoveries. Scientists have the knowledge and responsibility to present this information in both an understandable and interesting format. Most classrooms and homes are now connected to the internet, which can be utilized to provide more than a traditional 'flat' presentation. An interactive software package on planet detection has been developed. The major topics include: "1996 - The Break Through Year In Planet Detection"; "What Determines If A Planet Is Habitable?"; "How Can We Find Other Planets (Search Methods)"; "All About the Kepler Mission: How To Find Terrestrial Planets"; and "A Planet Detection Simulator". Using the simulator, the student records simulated observations and then analyzes and interprets the data within the program. One can determine the orbit and planet size, the planet's temperature and surface gravity, and finally determine if the planet is habitable. Originally developed for the Macintosh, a web based browser version is being developed.

  14. Popular Music in Taiwan.

    ERIC Educational Resources Information Center

    Wang, Georgette

    1986-01-01

    Discusses the recent concern over the imbalanced international flow of cultural products into Taiwan--such as films, television programs, and news from developed to developing nations--as it has fed the apprehension that imported popular music may have socialized Taiwanese audiences with alien values and ethics. (JD)

  15. Most Popular Campus

    ERIC Educational Resources Information Center

    Montgomery, Roger

    1973-01-01

    Foothill College owes its tremendous popularity to the fact that it neither fits into the tradition of the modern movement of architectural art, with its in-group language of heroic forms constructed in brute concrete, nor the more esoteric world that sees high art in commercial strip development and A & P parking lots. (Author)

  16. Television: Polysemy and Popularity.

    ERIC Educational Resources Information Center

    Fiske, John

    1986-01-01

    Argues that television programs must be polysemic to achieve popularity because of the wide variety of subcultures represented in the television audience. Analyzes two scenes from "Hart to Hart" to demonstrate the textual devices that bear the dominant ideology and those that resist it. (JD)

  17. Popularity in Wonderland.

    ERIC Educational Resources Information Center

    Nist, J.S.

    Specialists in the field of children's literature, who publish research and decide on awards for individual books, should give serious study to what children themselves choose to read. Among the children's books that were not originally awarded top honors by critics but that have proved extremely popular with children are the Oz books by L. Frank…

  18. Earth and Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    Jacobson, Seth A.; Walsh, Kevin J.

    2015-09-01

    The growth and composition of Earth is a direct consequence of planet formation throughout the Solar System. We discuss the known history of the Solar System, the proposed stages of growth and how the early stages of planet formation may be dominated by pebble growth processes. Pebbles are small bodies whose strong interactions with the nebula gas lead to remarkable new accretion mechanisms for the formation of planetesimals and the growth of planetary embryos. Many of the popular models for the later stages of planet formation are presented. The classical models with the giant planets on fixed orbits are not consistent with the known history of the Solar System, fail to create a high Earth/Mars mass ratio, and, in many cases, are also internally inconsistent. The successful Grand Tack model creates a small Mars, a wet Earth, a realistic asteroid belt and the mass-orbit structure of the terrestrial planets. In the Grand Tack scenario, growth curves for Earth most closely match a Weibull model. The feeding zones, which determine the compositions of Earth and Venus follow a particular pattern determined by Jupiter, while the feeding zones of Mars and Theia, the last giant impactor on Earth, appear to randomly sample the terrestrial disk. The late accreted mass samples the disk nearly evenly.

  19. Barnard’s Star: Planets or Pretense

    NASA Astrophysics Data System (ADS)

    Bartlett, Jennifer L.; Ianna, P. A.

    2014-01-01

    Barnard’s Star remains popular with planet hunters because it is not only an extremely near, high proper motion star, but also the object of early planet-detection claims. In 1963, van de Kamp explained perturbations in its proper motion by the presence of a planet. In 1969, he produced another single-planet solution and a two-planet solution to the astrometric wobbles detected. At least 19 studies have failed to confirm his results using a range of techniques, including radial velocity, direct imaging, and speckle interferometry. However, most of them lacked the sensitivity to detect the planets he described, including astrometric studies at the McCormick and Naval Observatories. However, radial-velocity monitoring of Barnard’s Star at Lick and Keck Observatories from 1987 through 2012 appears to have ruled out such planets. Based upon observations made at the Sproul Observatory between 1916 and 1962, van de Kamp claimed that Barnard’s Star had a planet with about 1.6 times the mass of Jupiter and an orbital period of 24 years. After accounting for instrumentation effects that might have been partially responsible for his initial results, he continued to assert that this red dwarf had two planets. In his 1982 analysis of ~20,000 exposures collected between 1938 and 1981, he calculated that two planets with 0.7- and 0.5-Jupiter masses in 12- and 20-year orbits, respectively, orbited the second-closest stellar system to our own. Starting in 1995, the dramatic successes of radial velocity searches for extrasolar planets drove van de Kamp’s unsubstantiated claims from popular consciousness. Although many low-mass stellar companions were discovered through astrometry, the technique has been less successful for planets: “The Extrasolar Planets Encyclopaedia” identifies one such discovery out of the 997 planets listed on 2013 September 23. Although Barnard’s Star has lost its pretensions to hosting the first extrasolar planets known, its intrinsic properties will keep it under observation. NSF grant AST 98-20711, Litton Marine Systems, Levinson Fund, University of Virginia, Hampden-Sydney College, and US Naval Observatory supported this research.

  20. Extrasolar Planets and Prospects for Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Marcy, Geoffrey W.; Butler, R. Paul; Vogt, Steven S.; Fischer, Debra A.

    2004-06-01

    Examination of 2000 sun--like stars has revealed 97 planets (as of 2002 Nov), all residing within our Milky Way Galaxy and within 200 light years of our Solar System. They have masses between 0.1 and 10 times that of Jupiter, and orbital sizes of 0.05--5 AU. Thus planets occupy the entire detectable domain of mass and orbits. News &summaries about extrasolar planets are provided at: http://exoplanets.org. These planets were all discovered by the wobble of the host stars, induced gravitationally by the planets, causing a periodicity in the measured Doppler effect of the starlight. Earth--mass planets remain undetectable, but space--based missions such as Kepler, COROT and SIM may provide detections of terrestrial planets within the next decade. The number of planets increases with decreasing planet mass, indicating that nature makes more small planets than jupiter--mass planets. Extrapolation, though speculative, bodes well for an even larger number of earth--mass planets. These observations and the theory of planet formation suggests that single sun--like stars commonly harbor earth--sized rocky planets, as yet undetectable. The number of planets increases with increasing orbital distance from the host star, and most known planets reside in non--circular orbits. Many known planets reside in the habitable zone (albeit being gas giants) and most newly discovered planets orbit beyond 1 AU from their star. A population of Jupiter--like planets may reside at 5--10 AU from stars, not easily detectable at present. The sun--like star 55 Cancri harbors a planet of 4--10 Jupiter masses orbiting at 5.5 AU in a low eccentricity orbit, the first analog of our Jupiter, albeit with two large planets orbiting inward. To date, 10 multiple--planet systems have been discovered, with four revealing gravitational interactions between the planets in the form of resonances. GJ 876 has two planets with periods of 1 and 2 months. Other planetary systems are ``hierarchical'', consisting of widely separated orbits. These two system architectures probably result from gravitational interactions among the planets and between the planets and the protoplanetary disk out of which they formed.

  1. Exploring the Living Planet with David Attenborough.

    ERIC Educational Resources Information Center

    Burgess, Jacquelin; Unwin, David

    1984-01-01

    In this interview David Attenborough, the celebrated natural history film maker and writer, talks about his highly successful television series, "The Living Planet." Devoted to the exposition of the world's ecosystems, the film represents a significant example of popular geographic education. (RM)

  2. Popular perceptions of Galileo

    NASA Astrophysics Data System (ADS)

    Sobel, Dava

    2010-01-01

    Among the most persistent popular misperceptions of Galileo is the image of an irreligious scientist who opposed the Catholic Church and was therefore convicted of heresy-was even excommunicated, according to some accounts, and denied Christian burial. In fact, Galileo considered himself a good Catholic. He accepted the Bible as the true word of God on matters pertaining to salvation, but insisted Scripture did not teach astronomy. Emboldened by his discovery of the Medicean Moons, he took a stand on Biblical exegesis that has since become the official Church position.

  3. PLANET-PLANET SCATTERING IN PLANETESIMAL DISKS

    SciTech Connect

    Raymond, Sean N.; Armitage, Philip J.; Gorelick, Noel

    2009-07-10

    We study the final architecture of planetary systems that evolve under the combined effects of planet-planet and planetesimal scattering. Using N-body simulations we investigate the dynamics of marginally unstable systems of gas and ice giants both in isolation and when the planets form interior to a planetesimal belt. The unstable isolated systems evolve under planet-planet scattering to yield an eccentricity distribution that matches that observed for extrasolar planets. When planetesimals are included the outcome depends upon the total mass of the planets. For M {sub tot} {approx}> 1 M{sub J} the final eccentricity distribution remains broad, whereas for M {sub tot} {approx}< 1 M{sub J} a combination of divergent orbital evolution and recircularization of scattered planets results in a preponderance of nearly circular final orbits. We also study the fate of marginally stable multiple planet systems in the presence of planetesimal disks, and find that for high planet masses the majority of such systems evolve into resonance. A significant fraction leads to resonant chains that are planetary analogs of Jupiter's Galilean satellites. We predict that a transition from eccentric to near-circular orbits will be observed once extrasolar planet surveys detect sub-Jovian mass planets at orbital radii of a {approx_equal} 5-10 AU.

  4. Is Venus a New Planet?

    NASA Astrophysics Data System (ADS)

    Fritzius, Robert S.

    2007-12-01

    In Worlds In Collision, MacMillan, 1950, Immanuel Velikovsky popularized the idea that Venus is a new planet, a fission product of Jupiter. And from about 1450 to 550 BCE, it participated in a series of close-encounters-of-the-worst-kind with Earth. His thesis was largely (and emphatically) rejected by the astronomical community. That rejection is still generally in effect. This, in spite of the fact, that his predictions about the Earth-Venus problem have been verified. This poster will summarize the Velikovsky scenario and list the solar system investigations which touch on each aspect.

  5. Dance of the Planets

    ERIC Educational Resources Information Center

    Riddle, Bob

    2005-01-01

    As students continue their monthly plotting of the planets along the ecliptic they should start to notice differences between inner and outer planet orbital motions, and their relative position or separation from the Sun. Both inner and outer planets have direct eastward motion, as well as retrograde motion. Inner planets Mercury and Venus,

  6. Dance of the Planets

    ERIC Educational Resources Information Center

    Riddle, Bob

    2005-01-01

    As students continue their monthly plotting of the planets along the ecliptic they should start to notice differences between inner and outer planet orbital motions, and their relative position or separation from the Sun. Both inner and outer planets have direct eastward motion, as well as retrograde motion. Inner planets Mercury and Venus,…

  7. Nebulous networks: Virginia Woolf and popular astronomy

    NASA Astrophysics Data System (ADS)

    Henry, Holly Grace

    This study investigates Virginia Woolf's fascination with advances in astronomy and telescopic technologies of the 1920s and 30s. Grounded in the cultural studies of science, and the work of theorists such as Donna Haraway and Bruno Latour, the dissertation reconstructs the complex interconnections between Woolf's fiction and prose writing and an explosive popular interest in astronomy and cosmology. Woolf's aesthetic and political practices were shaped by emerging visualization technologies ranging from astronomical telescopes to the hand-held camera. While her writing provides a focus for this investigation, the dissertation offers close readings of fiction and essays by multiple British authors and science writers in the context of these converging phenomena. As a result of glimpsing tiny worlds through her own telescope, Virginia Woolf formulated a global aesthetic and a global politics. Gazing at the moon and stars reminded her that earth is a planet in space, and that earth's inhabitants must rely on this small, fragile globe for their future survival. The opening chapter establishes the cultural context for the study. In 1923, the American astronomer Edwin Hubble determined that the Andromeda galaxy was located far beyond the limits of the Milky Way, then believed to comprise the entire universe. Hubble's radical reconfiguration of the universe contributed to a pervasive sense, in the modern period, of a decentering and re-scaling of humans in the universe. In the chapters that follow, the dissertation offers readings of Woolf's novels and short fiction in relation to her fascination with astronomy and explores how the wildly popular British cosmologist and science writer, Sir James jeans, had a shaping effect on popular culture and on Woolf's narrative practices and pacifist politics. Despite his oblique connections to what became Bloomsbury, jeans and his popular science texts were to play a considerable role in Woolf's formulation of a global aesthetic.

  8. Juggling Popularity and Quality: Literary Excellence vs. Popular Culture.

    ERIC Educational Resources Information Center

    Genco, Barbara A.; And Others

    1991-01-01

    Three librarians--Barbara A. Genco from Brooklyn, New York; Eleanor K. MacDonald from Beverly Hills, California; and Betsy Hearne from Chicago, Illinois--share their perspectives on where popular literature should fit into library material selection and children's reading diets. Popular literature is defined as primarily that which has first

  9. Tomorrow's Forecast: Oceans and Weather.

    ERIC Educational Resources Information Center

    Smigielski, Alan

    1995-01-01

    This issue of "Art to Zoo" focuses on weather and climate and is tied to the traveling exhibition Ocean Planet from the Smithsonian's National Museum of Natural History. The lessons encourage students to think about the profound influence the oceans have on planetary climate and life on earth. Sections of the lesson plan include: (1) "Ocean…

  10. Satisfaction Analysis of Experiential Learning-Based Popular Science Education

    ERIC Educational Resources Information Center

    Dzan, Wei-Yuan; Tsai, Huei-Yin; Lou, Shi-Jer; Shih, Ru-Chu

    2015-01-01

    This study employed Kolb's experiential learning model-specific experiences, observations of reflections, abstract conceptualization, and experiment-action in activities to serve as the theoretical basis for popular science education planning. It designed the six activity themes of "Knowledge of the Ocean, Easy to Know, See the Large from the…

  11. Popular Music: An Ongoing Challenge.

    ERIC Educational Resources Information Center

    Cutietta, Robert A.

    1991-01-01

    Addresses tendencies to force popular music into existing school music program formats, rather than include it as a form with its own musical integrity and authenticity. Urges music teachers not to dismiss popular music or turn it into elevator music. (CH)

  12. Rethinking Popular Culture and Media

    ERIC Educational Resources Information Center

    Marshall, Elizabeth, Ed.; Sensoy, Ozlem, Ed.

    2011-01-01

    "Rethinking Popular Culture and Media" is a provocative collection of articles that begins with the idea that the "popular" in classrooms and in the everyday lives of teachers and students is fundamentally political. This anthology includes outstanding articles by elementary and secondary public school teachers, scholars, and activists who…

  13. Rethinking Popular Culture and Media

    ERIC Educational Resources Information Center

    Marshall, Elizabeth, Ed.; Sensoy, Ozlem, Ed.

    2011-01-01

    "Rethinking Popular Culture and Media" is a provocative collection of articles that begins with the idea that the "popular" in classrooms and in the everyday lives of teachers and students is fundamentally political. This anthology includes outstanding articles by elementary and secondary public school teachers, scholars, and activists who

  14. Technology, Sound and Popular Music.

    ERIC Educational Resources Information Center

    Jones, Steve

    The ability to record sound is power over sound. Musicians, producers, recording engineers, and the popular music audience often refer to the sound of a recording as something distinct from the music it contains. Popular music is primarily mediated via electronics, via sound, and not by means of written notes. The ability to preserve or modify…

  15. Popular Culture and Democratic Practice.

    ERIC Educational Resources Information Center

    Dolby, Nadine

    2003-01-01

    A literature review explores how scholars have approached the study of popular culture--as text or lived experience. Examines the concepts of youth culture, individual agency, and cultural citizenship. Argues that the importance of popular culture lies in its role as a site for democratic practice. (Contains 88 reference notes.) (SK)

  16. New Dimensions in Popular Culture.

    ERIC Educational Resources Information Center

    Nye, Russel B., Ed.

    This document contains fifteen essays which study some of the didactic, moralistic literature which was popular in nineteenth century America, and speculate about the culture from which the literature evolved. The essays include "Millions of Moral Little Books: Sunday School Books in Their Popular Context"; "Nineteenth Century Gift Books: A…

  17. American Civilization--Popular Culture.

    ERIC Educational Resources Information Center

    Miller, Carol F.

    This syllabus introduces the purposes and organization of a course on Popular Culture as evidence of American civilization offered at Meramec Community College. The guide first presents a rationale for the study of popular culture and then lists course requirements; discusses techniques such as comparative analysis and psychoanalytic investigation…

  18. Terrestrial Planets: Comparative Planetology

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Papers were presented at the 47th Annual Meteoritical Society Meeting on the Comparative planetology of Terrestrial Planets. Subject matter explored concerning terrestrial planets includes: interrelationships among planets; plaentary evolution; planetary structure; planetary composition; planetary Atmospheres; noble gases in meteorites; and planetary magnetic fields.

  19. Kepler Planet Formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    2015-01-01

    Kepler has vastly increased our knowledge of planets and planetary systems located close to stars. The new data shows surprising results for planetary abundances, planetary spacings and the distribution of planets on a mass-radius diagram. The implications of these results for theories of planet formation will be discussed.

  20. Magma Oceans in the Inner Solar System

    NASA Astrophysics Data System (ADS)

    Elkins-Tanton, Linda T.

    2012-05-01

    Theory and observations point to the occurrence of magma ponds or oceans in the early evolution of terrestrial planets and in many early-accreting planetesimals. The apparent ubiquity of melting during giant accretionary impacts suggests that silicate and metallic material may be processed through multiple magma oceans before reaching solidity in a planet. The processes of magma ocean formation and solidification, therefore, strongly influence the earliest compositional differentiation and volatile content of the terrestrial planets, and they form the starting point for cooling to clement, habitable conditions and for the onset of thermally driven mantle convection and plate tectonics. This review focuses on evidence for magma oceans on planetesimals and planets and on research concerning the processes of compositional differentiation in the silicate magma ocean, distribution and degassing of volatiles, and cooling.

  1. Mission to Planet Earth

    NASA Technical Reports Server (NTRS)

    Tilford, Shelby G.; Koczor, Ron; Lee, Jonathan; Grady, Kevin J.; Hudson, Wayne R.; Johnston, Gordon I.; Njoku, Eni G.

    1990-01-01

    To preserve the earth, it is necessary to understand the tremendously complex interactions of the atmosphere, oceans, land, and man's activities deeply enough to construct models that can predict the consequences of our actions and help us make sound environmental, energy, agriculture, and economic decisions. Mission to Planet Earth is NASA's suggested share and the centerpiece of the U.S. contribution to understanding the environment, the Global Change Research Program. The first major element of the mission would be the Earth Observing System, which would give the simultaneous, comprehensive, long-term earth coverage lacking previously. NASA's Geosynchronous Earth Observatory with two additional similar spacecraft would be orbited by the U.S., plus one each by Japan and the European Space Agency. These would be the first geostationary satellites to span all the disciplines of the earth sciences. A number of diverse data gathering payloads are also planned to be carried aboard the Polar Orbiting Platform. Making possible the long, continuous observations planned and coping with the torrent of data acquired will require technical gains across a wide front. Finally, how all this data is consolidated and disseminated by the EOS Data and Information System is discussed.

  2. Extrasolar planets: constraints for planet formation models.

    PubMed

    Santos, Nuno C; Benz, Willy; Mayor, Michel

    2005-10-14

    Since 1995, more than 150 extrasolar planets have been discovered, most of them in orbits quite different from those of the giant planets in our own solar system. The number of discovered extrasolar planets demonstrates that planetary systems are common but also that they may possess a large variety of properties. As the number of detections grows, statistical studies of the properties of exoplanets and their host stars can be conducted to unravel some of the key physical and chemical processes leading to the formation of planetary systems. PMID:16224012

  3. DETECTING VOLCANISM ON EXTRASOLAR PLANETS

    SciTech Connect

    Kaltenegger, L.; Sasselov, D. D.; Henning, W. G.

    2010-11-15

    The search for extrasolar rocky planets has already found the first transiting rocky super-Earth, Corot 7b, with a surface temperature that allows for magma oceans. Here, we investigate whether we could distinguish rocky planets with recent major volcanism by remote observation. We develop a model for volcanic eruptions on an Earth-like exoplanet based on the present-day Earth and derive the observable features in emergent and transmission spectra for multiple scenarios of gas distribution and cloud cover. We calculate the observation time needed to detect explosive volcanism on exoplanets in primary as well as secondary eclipse and discuss the likelihood of observing volcanism on transiting Earth-sized to super-Earth-sized exoplanets. We find that sulfur dioxide from large explosive eruptions does present a spectral signal that is remotely detectable especially for secondary eclipse measurements around the closest stars and ground-based telescopes, and report the frequency and magnitude of the expected signatures. The transit probability of a planet in the habitable zone decreases with distance from the host star, making small, nearby host stars the best targets.

  4. Planet Demographics from Transits

    NASA Astrophysics Data System (ADS)

    Howard, Andrew

    2015-08-01

    From the demographics of planets detected by the Kepler mission, we have learned that there exists approximately one planet per star for planets larger than Earth orbiting inside of 1 AU. We have also learned the relative occurrence of these planets as a function of their orbital periods, sizes, and host star masses and metallicities. In this talk I will review the key statistical findings that the planet size distribution peaks in the range 1-3 times Earth-size, the orbital period distribution is characterized by a power-law cut off at short periods, small planets are more prevalent around small stars, and that approximately 20% of Sun-like stars hosts a planet 1-2 times Earth-size in a habitable zone. Looking forward, I will describe analysis of photometry from the K2 mission that is yielding initial planet discoveries and offering the opportunity to measure planet occurrence in widely separated regions of the galaxy. Finally, I will also discuss recent techniques to discover transiting planets in space-based photometry and to infer planet population properties from the ensemble of detected and non-detected transit signals.

  5. Popular Culture in the Classroom

    ERIC Educational Resources Information Center

    Allender, Dale

    2004-01-01

    Traditional and innovative elements such as bells and music with quick pacing accented by a voice that students could recognize is used to effortlessly bring students to the classroom. Popular culture is shown to work well using classroom examples.

  6. Early societies popularize scientific research.

    PubMed

    Hackmann, W D

    1983-01-01

    Private scientific societies, popular in the eighteenth century, supported and encouraged research on such devices as the electrostatic generator and the Leyden jar, paving the way for later electrophysiological research. PMID:6358812

  7. Planet Masses and Densities

    NASA Astrophysics Data System (ADS)

    Marcy, Geoffrey W.

    2012-05-01

    The masses of Kepler planet candidates remain unknown until some dynamical technique measures the gravitational effect of that planet on either the star (with RV measurements) or other planets (with TTVs). Measuring planet masses is particularly important as, when combined with the transit-based planet radii, they yield the bulk density of the planets, constraining conditions in the interior, notably the amount of metal, rock, water, and gas. For planets smaller than 2 Earth-radii, the transition from Neptune-like to rocky planets is particularly intriguing, bearing on formation, evolution, and habitability. We report precise (2 m/s) Doppler RVs for 15 host stars of Kepler planet candidates. New RV techniques are now employed for faint stars of 13th mag, notably long-slit sky subtraction and statistical priors for the PSF and wavelength scale in the Doppler analysis. The RV observations are timed at moments near orbital quadrature to maximize the RV differences. We obtained 10-20 RVs for each of 15 host stars of Kepler planet candidates, with typical exposure times of 30 min. The RVs are fit with Keplerian models that include all transisting planets and their known ephemerides from the Kepler photometry. The two free parameters are only the masses of the planets and RV zero point. Both random and systematic errors will not be correlated with orbital phase, ensuring that the RV signal-to-noise improves as the square root of the number of RV observations. Orbital fits provide planet mass, density, and in some cases contraints on eccentricity. For RV non-detections, MCMC analyses provide upper limits to planet mass and density.

  8. Snowball Planets: A Possible Type of Water-Rich Terrestrial Planet in Extrasolar Planetary Systems

    NASA Astrophysics Data System (ADS)

    Tajika, E.

    2008-12-01

    Existence of liquid water on the planetary surface is essential for life. However, terrestrial planets with abundant water have multiple climate modes, including an ice-free, a partially ice-covered, and a globally ice- covered state, even when the incident flux from the central star and the abundance of greenhouse gasses in the atmosphere are the same. This multiplicity of climate mode is derived from large difference in the albedo of ice and water. Recent geological studies have revealed that the Earth experienced global glaciations ("snowball Earth" events) in its history. In the snowball glaciations, liquid water is thought to have existed under the ice shell because of geothermal heat flow from the Earth"fs interior. By analogy with the snowball glaciations, I discuss the conditions for an extrasolar terrestrial planet which is covered with ice but has an internal ocean for the timescale of planetary evolution owing to geothermal heat flow from the planetary interior. I show that liquid water can exist if the planetary mass and the water abundance are comparable to the Earth, although a planet with a mass of <0.4 Me (Me is the Earth's mass) would not be able to maintain the internal ocean. Liquid water would be absolutely stable for a planet with a mass of >4 Me (i.e., super- Earth), irrespective of planetary orbit and luminosity of the central star. It is therefore implied that super-Earth inevitably have liquid water either on its surface (for the ice-freee or partially ice-covered modes) or beneath the ice (for the globally ice-covered mode). Searches for terrestrial planets in extrasolar planetary systems should consider such a "snowball planet", which is a possible type of water-rich terrestrial planet other than an Earth-like "ocean planet". Because a snowball planet is much brighter than (more than twice) an ocean planet with the same size, it would be a good target for the astronomical observation in the future.

  9. The planet Jupiter

    NASA Astrophysics Data System (ADS)

    Encrenaz, Thrse

    The exploration of Jupiter, the closest and biggest giant planet, has provided key information about the origin and evolution of the outer Solar system. Our knowledge has strongly benefited from the Voyager and Galileo space missions. We now have a good understanding of Jupiter's thermal structure, chemical composition and magnetospheric environment. There is still debate about the nature of the heating source responsible for the high thermospheric temperatures (precipitating particles and/or gravity waves). The measurement of elemental abundance ratios (C/H, N/H, S/H) gives strong support to the "nucleation" formation model, according to which giant planets formed from the accretion of an initial core and the collapse of the surrounding gaseous protosolar nebula. The D/H and 3He/4He ratios are found to be representative of their protosolar value. The helium abundance, in contrast, appears to be slightly depleted in the outer envelope with respect to the protosolar value; this departure is interpreted as an evolutionary effect, due to the condensation of helium droplets in the liquid hydrogen ocean inside Jupiter's interior. The cloud structure of Jupiter, characterized by the belt-zone system, is globally understood; also present are specific features like regions of strong infrared radiation ("hot spots"), colder regions ("white ovals") and the Great Red Spot (GRS). Clouds were surprisingly absent at the hot spot corresponding to the Galileo probe entry site, and the water abundance measured there was strongly depleted with respect to the solar O/H value. This probably implies that hot spots are dry, cloud-free regions of subsidence, while "normal" air, rich in condensibles, is transported upward by convective motions. As a result, the Jovian meteorology, still based on Halley-type cells, seems to be much more complex than a simple zone-belt system. The nature of the GRS, a giant anticyclonic storm, colder and higher than its environment, has been confirmed by the Galileo observations, but its internal structure appears to be very complex. Strong winds, probably driven by the Jovian internal source, were measured at deep tropospheric levels. The troposphere might be statically stable at pressures higher than 18 bars, but the extent of this putative radiative layer is still unknown.

  10. Wave of a Planet

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This plot tells astronomers that a fifth planet is in orbit around the star 55 Cancri, making the star the record-holder for hosting the most known exoplanets.

    As planets circle around their stars, they cause the stars to wobble back and forth in a regular pattern. By looking for this motion in a star, scientists can find planets that can't be seen with telescopes.

    The wobble caused by the fifth planet discovered around 55 Cancri is represented here by the sinuous line in blue. The actual data points are yellow and error bars are the lines above and below the yellow dots. The cycle of the wobble indicates that the planet circles around its star about every 260 days. The amplitude of the wobble indicates that the planet is a giant at least 45 times the mass of Earth.

    The wobbles caused by the other four planets has been removed from this plot, to reveal that caused by the fifth. The departure from a perfect sine wave suggests the planet's orbit is not perfectly circular.

    Because 55 Cancri has multiple planets, the star had to be observed for a long time before astronomers could find and confirm its fifth planet. These data were collected over a period of 18 years using both the Lick Observatory near San Jose, Calif., and the W.M. Keck Observatory in Hawaii.

  11. The Freezing Conditions of Planets: Effect of Obliquity

    NASA Astrophysics Data System (ADS)

    Abe, Y.; Abe-Ouchi, A.

    2002-12-01

    Condition for the occurrence of the completely frozen state (a "snow-ball" state) might be a critical measure related to the habitability of the planet. It is investigated with a particular reference to the obliquity for both a land planet case and an aqua planet case. Obliquity change may cause freezing and unfreezing of planet if the freezing condition depends on the obliquity. Effect of obliquity on the freezing is also an important issue for the investigation of the paleo-Mars. Here we investigated the freezing condition by a general circulation model, CCSR/NIES AGCM 5.4g. We applied the Earth condition, but assumed no topography and applied a bucket model with the saturation depth of 10 cm for ground water calculation for the land planet case and 50m slab ocean for the aqua planet case. The results are summarized as follows: 1. A land planet shows stronger resistance to the complete freezing than an aqua planet. 2. A land planet in an oblique regime falls in the completely frozen state at a smaller solar constant than an upright regime. 3. On a land planet in an oblique regime, low latitude area is more susceptible to freezing than the mid latitude area. Implication for the paleo-Mars will be discussed in the presentation.

  12. In search of planet Vulcan. The ghost in Newton's clockwork universe.

    NASA Astrophysics Data System (ADS)

    Baum, R.; Sheehan, W.

    Presented for the first time in popular form is the story of the search for the phantom planet Vulcan. It is rich in the eccentricities of human character, of astronomers far from the popular ideal. There is the autocratic Urbain J. J. Le Verrier, the mathematician who essentially created Vulcan, and James Craig Watson, who made the most credible (but disputed) observations of the planet at the July 1878 eclipse.

  13. Popularizing Space Education in Indian Context

    NASA Astrophysics Data System (ADS)

    Yalagi, Amrut

    Indians have many mythological stories about many constellations and stars. Hindu months are based on MOON and 27 stars on Zodiac. They are very important for many Indians in ritual, religious functions. By prompting them to identify their birth star, really makes them elevated. Similarly conveying them the importance of star gazing with respect to their day today life makes them to take interest and active participation in Space Activities. Space activities should be driven by public; their requirements; their dreams and imaginations. Their active participation definitely gives valuable inputs to space scientists. Hence, there is a need of involving common man or public mass by appropriate motivation by organising sky gazing sessions, exhibitions, workshops, etc. In this connection, even if the some organisation are able to attract a small percent of qualified engineers/scientists,, enthusiastic students, it would result in the creation of a sizable pool of talent in space sciences,which may well determine the future mankind on this planet. Some simple motivation acts have made the people to take interest in space. we have been using certain methodologies to popularize space science - 1] Conducting theory sessions on basics of star gazing and conveying importance of sky gazing with respect to day-today life. 2] Organising seminars, workshops, lectures and other academic/popular science activities with special reference to space science 3] Projects - a] Cubsat Missions b] Automatic Weather Station Facility c] Model making d] Creating and simulating space models and rover making competitions. The 50 year's of Exploration has left tremendous impact on many society's working towards space education and exploration.

  14. Popular Culture and the Teaching of English.

    ERIC Educational Resources Information Center

    Donelson, Ken, Ed.

    1975-01-01

    This issue of the "Arizona English Bulletin" contains 38 articles related to popular culture and the teaching of English. The articles discuss such topics as language in the popular arts, establishing a popular culture library, defining sexism in popular culture, detective literature and its uses in the traditional classroom, popular literature as…

  15. A Maximum Radius for Habitable Planets

    NASA Astrophysics Data System (ADS)

    Alibert, Yann

    2015-09-01

    We compute the maximum radius a planet can have in order to fulfill two constraints that are likely necessary conditions for habitability: 1- surface temperature and pressure compatible with the existence of liquid water, and 2- no ice layer at the bottom of a putative global ocean, that would prevent the operation of the geologic carbon cycle to operate. We demonstrate that, above a given radius, these two constraints cannot be met: in the Super-Earth mass range (1-12 Mearth), the overall maximum that a planet can have varies between 1.8 and 2.3 Rearth. This radius is reduced when considering planets with higher Fe/Si ratios, and taking into account irradiation effects on the structure of the gas envelope.

  16. A Maximum Radius for Habitable Planets.

    PubMed

    Alibert, Yann

    2015-09-01

    We compute the maximum radius a planet can have in order to fulfill two constraints that are likely necessary conditions for habitability: 1- surface temperature and pressure compatible with the existence of liquid water, and 2- no ice layer at the bottom of a putative global ocean, that would prevent the operation of the geologic carbon cycle to operate. We demonstrate that, above a given radius, these two constraints cannot be met: in the Super-Earth mass range (1-12 Mearth), the overall maximum that a planet can have varies between 1.8 and 2.3 Rearth. This radius is reduced when considering planets with higher Fe/Si ratios, and taking into account irradiation effects on the structure of the gas envelope. PMID:26159097

  17. Planet Formation - Overview

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    2005-01-01

    Modern theories of star and planet formation are based upon observations of planets and smaller bodies within our own Solar System, exoplanets &round normal stars and of young stars and their environments. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth as do terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. These models predict that rocky planets should form in orbit about most single stars. It is uncertain whether or not gas giant planet formation is common, because most protoplanetary disks may dissipate before solid planetary cores can grow large enough to gravitationally trap substantial quantities of gas. A potential hazard to planetary systems is radial decay of planetary orbits resulting from interactions with material within the disk. Planets more massive than Earth have the potential to decay the fastest, and may be able to sweep up smaller planets in their path.

  18. Terrestrial planet formation

    PubMed Central

    Righter, K.; O’Brien, D. P.

    2011-01-01

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (∼106 y), followed by planetesimals to embryos (lunar to Mars-sized objects; few × 106 y), and finally embryos to planets (107–108 y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids. PMID:21709256

  19. Terrestrial planet formation.

    PubMed

    Righter, K; O'Brien, D P

    2011-11-29

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids. PMID:21709256

  20. Popular Education in Solidarity Economy

    ERIC Educational Resources Information Center

    de Melo Neto, José Francisco; da Costa, Francisco Xavier Pereira

    2015-01-01

    This article seeks to show the relation between popular education and solidarity economy in experiences of solidarity economy enterprises in Brazil. It is based on diverse experiences which have occurred in various sectors of this economy, highlighting those experiences which took place in João Pessoa with the creation of a Cooperative of Workers…

  1. Popular Education in Solidarity Economy

    ERIC Educational Resources Information Center

    de Melo Neto, Jos Francisco; da Costa, Francisco Xavier Pereira

    2015-01-01

    This article seeks to show the relation between popular education and solidarity economy in experiences of solidarity economy enterprises in Brazil. It is based on diverse experiences which have occurred in various sectors of this economy, highlighting those experiences which took place in Joo Pessoa with the creation of a Cooperative of Workers

  2. Readers' Knowledge of Popular Genre

    ERIC Educational Resources Information Center

    Dixon, Peter; Bortolussi, Marisa

    2009-01-01

    This research examined readers' knowledge of popular genres. Participants wrote short essays on fantasy, science fiction, or romance. The similarities among the essays were measured using latent semantic analysis (LSA) and were then analyzed using multidimensional scaling and cluster analysis. The clusters and scales were interpreted by searching…

  3. Popular Music in Early Adolescence.

    ERIC Educational Resources Information Center

    Christenson, Peter G.; Roberts, Donald F.

    This paper examines young adolescents' involvement with popular music and the health implications of that involvement. Initial discussion explores three central concepts: music media, adolescence, and mass media effects. A summary of research on music media in adolescence is offereed in two sections discussing exposure to, and gratifications and…

  4. Teaching the French Popular Front.

    ERIC Educational Resources Information Center

    Wall, Irwin M.

    1987-01-01

    Examines the French Popular Front of 1936 as a vehicle to investigate the turbulent decade of the 1930s. Reviews current historiography and discusses various facets of Leon Blum's government, examining the interrelationship of major economic and political forces. Concludes that the French Left still faces Blum's dilemma of implementing socialism…

  5. Popular Fiction as Liberal Art.

    ERIC Educational Resources Information Center

    Stowe, William W.

    1986-01-01

    Analyzes popular fiction, particularly the detective novel, using Ruth Rendell's "An Unkindness of Ravens" as an example. Calls detective fiction political literature and claims that it gives readers a chance to affirm or criticize the dynamics of the confrontation of society and crime. (SRT)

  6. Popularity Ends at Grade 12!

    ERIC Educational Resources Information Center

    Rimm, Sylvia B.

    1988-01-01

    This presentation of a speech to gifted teenagers discusses the pressures of giftedness. It focuses on the demands placed on gifted teenagers by others and by themselves, their need to develop self-confidence, their uniqueness and yet similarities with others, the balance between creativity and conformity, and the unimportance of popularity. (JDD)

  7. Outer Planet Icy Satellites

    NASA Technical Reports Server (NTRS)

    Buratti, B.

    1994-01-01

    An outer planet icy satellite is any one of the celestial bodies in orbit around Jupiter, Saturn, Uranus, Neptune, or Pluto. They range from large, planet-like geologically active worlds with significant atmospheres to tiny irregular objects tens of kilometers in diameter. These bodies are all believed to have some type of frozen volatile, existing alone or in combination with other volatiles.

  8. Outer planet satellites

    NASA Technical Reports Server (NTRS)

    Schenk, Paul M.

    1991-01-01

    Recent findings on the outer-planet satellites are presented, with special consideration given to data on the rheologic properties of ice on icy satellites, the satellite surfaces and exogenic processes, cratering on dead cratered satellites, volcanism, and the interiors of outer-planet satellites. Particular attention is given to the state of Titan's surface and the properties of Triton, Pluto, and Charon.

  9. March of the Planets

    ERIC Educational Resources Information Center

    Thompson, Bruce

    2007-01-01

    The motion of the planets in their orbits can be demonstrated to students by using planetarium software programs. These allow time to be sped up so that the relative motions are readily observed. However, it is also valuable to have the students understand the real speed of the planets in their orbits. This paper describes an exercise that gives

  10. Planets in Motion

    ERIC Educational Resources Information Center

    Riddle, Bob

    2005-01-01

    All the planets in the solar system revolve around the Sun in the same direction, clockwise when viewed from above the North Pole. This is referred to as direct motion. From the perspective on the Earth's surface, the planets travel east across the sky in relation to the background of stars. The Sun also moves eastward daily, but this is an

  11. Name That Planet!

    ERIC Educational Resources Information Center

    Beck, Judy; Rust, Cindy

    2002-01-01

    Presents an activity in which students in groups explore one planet in the solar system and present their findings to the whole class. Focuses on the planet's location in the solar system, geological features, rate of revolutions, and calendar year. (YDS)

  12. March of the Planets

    ERIC Educational Resources Information Center

    Thompson, Bruce

    2007-01-01

    The motion of the planets in their orbits can be demonstrated to students by using planetarium software programs. These allow time to be sped up so that the relative motions are readily observed. However, it is also valuable to have the students understand the real speed of the planets in their orbits. This paper describes an exercise that gives…

  13. Planets in Motion

    ERIC Educational Resources Information Center

    Riddle, Bob

    2005-01-01

    All the planets in the solar system revolve around the Sun in the same direction, clockwise when viewed from above the North Pole. This is referred to as direct motion. From the perspective on the Earth's surface, the planets travel east across the sky in relation to the background of stars. The Sun also moves eastward daily, but this is an…

  14. Comparative Climatology of Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Mackwell, Stephen J.; Simon-Miller, Amy A.; Harder, Jerald W.; Bullock, Mark A.

    Public awareness of climate change on Earth is currently very high, promoting significant interest in atmospheric processes. We are fortunate to live in an era where it is possible to study the climates of many planets, including our own, using spacecraft and groundbased observations as well as advanced computational power that allows detailed modeling. Planetary atmospheric dynamics and structure are all governed by the same basic physics. Thus differences in the input variables (such as composition, internal structure, and solar radiation) among the known planets provide a broad suite of natural laboratory settings for gaining new understanding of these physical processes and their outcomes. Diverse planetary settings provide insightful comparisons to atmospheric processes and feedbacks on Earth, allowing a greater understanding of the driving forces and external influences on our own planetary climate. They also inform us in our search for habitable environments on planets orbiting distant stars, a topic that was a focus of Exoplanets, the preceding book in the University of Arizona Press Space Sciences Series. Quite naturally, and perhaps inevitably, our fascination with climate is largely driven toward investigating the interplay between the early development of life and the presence of a suitable planetary climate. Our understanding of how habitable planets come to be begins with the worlds closest to home. Venus, Earth, and Mars differ only modestly in their mass and distance from the Sun, yet their current climates could scarcely be more divergent. Our purpose for this book is to set forth the foundations for this emerging science and to bring to the forefront our current understanding of atmospheric formation and climate evolution. Although there is significant comparison to be made to atmospheric processes on nonterrestrial planets in our solar system — the gas and ice giants — here we focus on the terrestrial planets, leaving even broader comparisons to a future volume. Our authors have taken on the task to look at climate on the terrestrial planets in the broadest sense possible — by comparing the atmospheric processes at work on the four terrestrial bodies, Earth, Venus, Mars, and Titan (Titan is included because it hosts many of the common processes), and on terrestrial planets around other stars. These processes include the interactions of shortwave and thermal radiation with the atmosphere, condensation and vaporization of volatiles, atmospheric dynamics, chemistry and aerosol formation, and the role of the surface and interior in the long-term evolution of climate. Chapters herein compare the scientific questions, analysis methods, numerical models, and spacecraft remote sensing experiments of Earth and the other terrestrial planets, emphasizing the underlying commonality of physical processes. We look to the future by identifying objectives for ongoing research and new missions. Through these pages we challenge practicing planetary scientists, and most importantly new students of any age, to find pathways and synergies for advancing the field. In Part I, Foundations, we introduce the fundamental physics of climate on terrestrial planets. Starting with the best studied planet by far, Earth, the first chapters discuss what is known and what is not known about the atmospheres and climates of the terrestrial planets of the solar system and beyond. In Part II, Greenhouse Effect and Atmospheric Dynamics, we focus on the processes that govern atmospheric motion and the role that general circulation models play in our current understanding. In Part III, Clouds and Hazes, we provide an in-depth look at the many effects of clouds and aerosols on planetary climate. Although this is a vigorous area of research in the Earth sciences, and very strongly influences climate modeling, the important role that aerosols and clouds play in the climate of all planets is not yet well constrained. This section is intended to stimulate further research on this critical subject. The study of climate involves much more than understanding atmospheric processes. This subtlety is particularly appreciated for Earth, where chemical cycles, geology, ocean influences, and biology are considered in most climate models. In Part IV, Surface and Interior, we look at the role that geochemical cycles, volcanism, and interior mantle processes play in the stability and evolution of terrestrial planetary climates. There is one vital commonality between the climates of all the planets of the solar system: Regardless of the different processes that dominate each of the climates of Earth, Mars, Venus, and Titan, they are all ultimately forced by radiation from the same star, albeit at variable distances. In Part V, Solar Influences, we discuss how the Sun's early evolution affected the climates of the terrestrial planets, and how it continues to control the temperatures and compositions of planetary atmospheres. This will be of particular interest as models of exoplanets, and the influences of much different stellar types and distances, are advanced by further observations. Comparisons of atmospheric and climate processes between the planets in our solar system has been a focus of numerous conferences over the past decade, including the Exoclimes conference series. In particular, this book project was closely tied to a conference on Comparative Climatology of Terrestrial Planets that was held in Boulder, Colorado, on June 25-28, 2012. This book benefited from the opportunity for the author teams to interact and obtain feedback from the broader community, but the chapters do not in general tie directly to presentations at the conference. The conference, which was organized by a diverse group of atmospheric and climate scientists led by Mark Bullock and Lori Glaze, sought to build connections between the various communities, focusing on synergies and complementary capabilities. Discussion panels at the end of most sessions served to build connections between planetary, solar, astrophysics, and Earth climate scientists. These presentations and discussions allowed broadening of the author teams and tuning of the material in each chapter. Comparative Climatology of Terrestrial Planets is the 38th book in the University of Arizona Press Space Sciences Series. The support and guidance from General Editor Richard Binzel has been critical in timely production of a quality volume. Renée Dotson of the Lunar and Planetary Institute, with support from Elizabeth Cunningham and Katy Buckaloo, provided outstanding help in the management of the book project and especially in the preparation of the chapters for publication. Her quiet reminders and attention to detail are critical in making the Space Science Series such an asset for the planetary science community. As for so many other books in this series, William Hartmann used his artistic skills to masterfully capture the book's theme. Much gratitude is owed to Adriana Ocampo of NASA Headquarters for her support of both the conference and book projects and her shepherding of the NASA contributions from the diverse groups within the Science Mission Directorate. Equally, James Green and Jonathan Rall of NASA Headquarters provided the financial resources and corporate oversight that helped make this book project such a success.

  15. Magma Ocean Lifetimes

    NASA Astrophysics Data System (ADS)

    Valencia, D.; O'Connell, R. J.; Pierrehumbert, R. T.

    2008-12-01

    The early evolution of a terrestrial planet may play an important role in its subsequent thermal evolution. Terrestrial super-Earths are expected to evolve similarly to terrestrial planets: quickly cooling from a magma ocean state, in which they experience high surface heat fluxes and temperatures. We study the solidification of magma oceans in terrestrial super-Earths and determine how long this phase lasts in the presence and absence of an atmosphere (grey and water-vapor). In the blackbody approximation the timescales are of order 105 years, while in a grey approximation the timescales can be extended to a few million years for an optically thick atmosphere (τ =100). We find that a 10 earth-mass planet takes about twice as long to cool as a one earth-mass planet. This early epoch is the most amenable to direct observation due to the high planetary heat flux; depending on how long it lasts it might be possible to directly detect super-Earths in this hot state. Development of more sophisticated atmospheric models may allow the inference of outgassing products from spectral signatures.

  16. The deep ocean under climate change

    NASA Astrophysics Data System (ADS)

    Levin, Lisa A.; Le Bris, Nadine

    2015-11-01

    The deep ocean absorbs vast amounts of heat and carbon dioxide, providing a critical buffer to climate change but exposing vulnerable ecosystems to combined stresses of warming, ocean acidification, deoxygenation, and altered food inputs. Resulting changes may threaten biodiversity and compromise key ocean services that maintain a healthy planet and human livelihoods. There exist large gaps in understanding of the physical and ecological feedbacks that will occur. Explicit recognition of deep-ocean climate mitigation and inclusion in adaptation planning by the United Nations Framework Convention on Climate Change (UNFCCC) could help to expand deep-ocean research and observation and to protect the integrity and functions of deep-ocean ecosystems.

  17. Wobbling Toward Planet Detection

    NASA Astrophysics Data System (ADS)

    Marcy, G. W.

    1995-12-01

    Several techniques have matured during the past year which enable indirect detection of planets orbiting main sequence stars. These methods include: RADIAL VELOCITIES, LONG BASELINE INTERFEROMETRY (astrometric, not imaging), LARGE TELESCOPE ASTROMETRY, TRANSITS BY TERRESTRIAL PLANETS, and GRAVITATIONAL LENSING. Current velocity precision is better than 10 m/s (at several observatories) which enables detection of jupiter-like planets within 5AU. Ground-based astrometry by Gatewood achieves a precision of 0.001arcsec, sufficient to detect jupiter-like planets orbiting >5AU from nearby stars. The above two techniques will soon benefit from larger aperture (Keck, HET, VLT) and superior seeing. Future ground-based interferometric astrometry should be able to detect planets like Uranus and Neptune. Detection of terrestrial planets are possible, in principle, with techniques of transits or lensing. I will review each of the above techniques with regard to instrumentation status and ultimate usefulness. I will report the results to date of on-going projects to detect planetary systems, especially from velocities and single-aperture astrometry. The status of the companion to 51 Pegasus and other reported planets will be described.

  18. The Effect of High-Pressure Ice Layer on Ice-Covered Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Ueta, S.

    2014-04-01

    A lot of extrasolar terrestrial planets have been discovered. Whether terrestrial planets with liquid H2O exist is an important question to consider, especially in terms of the planets' habitability. Even in a globally ice-covered state, liquid water could exist beneath the surface ice shell because sufficient geothermal heat flow from the planetary interior could melt the interior ice, so that an internal ocean under the surface ice shell could appear. In this study, we argue the conditions under which ice-covered terrestrial planets have an internal ocean on the timescale of planetary evolution (Ueta & Sasaki 2013). Geothermal heat flow calculated by a parameterized convection model is considered as the heat source at the origin of the internal ocean. We also examine how the amount of radiogenic heat and H2O mass affect these conditions. Moreover, we investigate the structures of surface H2O layers of ice-covered planets by considering the effects of ice under high pressure (high-pressure ice). At 1 AU from the central star, a 1M_Earth planet with 0.6-25 times H2O mass of the Earth could have an internal ocean. When the planet has an H2O mass over 25 times that of the Earth, high-pressure ice layers may appear between the internal ocean and the rock-part of the planet. The results indicate that planetary size and surface H2O mass strongly ristrict the conditions required for an extrasolar terrestrial planet to have an internal ocean without high-pressure ice existing under the internal ocean. The habitability of a planet might be influenced by the existence of such high-pressure ice layers.

  19. The Gemini Planet Imager

    SciTech Connect

    Macintosh, B; al., e

    2006-05-02

    The next major frontier in the study of extrasolar planets is direct imaging detection of the planets themselves. With high-order adaptive optics, careful system design, and advanced coronagraphy, it is possible for an AO system on a 8-m class telescope to achieve contrast levels of 10{sup -7} to 10{sup -8}, sufficient to detect warm self-luminous Jovian planets in the solar neighborhood. Such direct detection is sensitive to planets inaccessible to current radial-velocity surveys and allows spectral characterization of the planets, shedding light on planet formation and the structure of other solar systems. We have begun the construction of such a system for the Gemini Observatory. Dubbed the Gemini Planet Imager (GPI), this instrument should be deployed in 2010 on the Gemini South telescope. It combines a 2000-actuator MEMS-based AO system, an apodized-pupil Lyot coronagraph, a precision infrared interferometer for real-time wavefront calibration at the nanometer level, and a infrared integral field spectrograph for detection and characterization of the target planets. GPI will be able to achieve Strehl ratios > 0.9 at 1.65 microns and to observe a broad sample of science targets with I band magnitudes less than 8. In addition to planet detection, GPI will also be capable of polarimetric imaging of circumstellar dust disks, studies of evolved stars, and high-Strehl imaging spectroscopy of bright targets. We present here an overview of the GPI instrument design, an error budget highlighting key technological challenges, and models of the system performance.

  20. Gravitational heating of planets

    NASA Astrophysics Data System (ADS)

    Horedt, G. P.

    1980-01-01

    Analytical estimates for three important and general planetary heating processes, excluding radioactive heating, are presented: accretional heating, adiabatic compression and core formation. The relative importance of these processes appears to be as follows. Accretional heating is important for almost all planets and satellites including asteroid-size bodies. Heating due to core formation becomes important for objects which are similar to, or larger than the terrestrial planets. Compressional heating is important only for the outer cores and the envelopes of the giant planets, provided that they are heated, before compression, up to about 1000 K.

  1. The planets and life.

    NASA Technical Reports Server (NTRS)

    Young, R. S.

    1971-01-01

    It is pointed out that planetary exploration is not simply a program designed to detect life on another planet. A planet similar to earth, such as Mars, when studied for evidence as to why life did not arise, may turn out to be scientifically more important than a planet which has already produced a living system. Of particular interest after Mars are Venus and Jupiter. Jupiter has a primitive atmosphere which may well be synthesizing organic molecules today. Speculations have been made concerning the possibility of a bio-zone in the upper atmosphere of Venus.

  2. A Definition of Planet

    NASA Astrophysics Data System (ADS)

    Durand-Manterola, H. J.

    2005-12-01

    It had proposed some definitions about what a planet is. It seems clear that the planet's mass superior limit should be lower than the threshold for deuterium thermonuclear fusion. However the inferior limit is more elusive. It had proposed either Pluto's mass or the minimum mass to produce a spherical form. The Working Group on Extrasolar Planets (WGESP) of the International Astronomical Union (IAU) gives the next definition of a planet: 'Object with the true mass below the limiting mass for thermonuclear fusion of deuterium (currently calculate to be 13 Jupiter masses for objects of solar metalicity) that orbit stars or stellar remanents (no matter how they formed). The minimum mass/size required for an extrasolar object to be considered a planet should be the same as that used in our Solar System' . The definition gave by Marcy and Butler (2000) is: 'A planet is an object that has a mass between that of Pluto and the Deuterium-burning threshold and that forms in orbit around an object that can generate energy by nuclear reactions' These definitions are not satisfactory because they have some statements that are not clear. By example, the minimum mass the IAU group defines in term of the minimum mass to the Solar System but this is not defined in the first instance, unless we take the mass of Pluto as defined by Marcy and Butler. But why the mass of Pluto should be the minimum mass? Which is the physical reason to choose this one as the minimum of mass? On the other hand the two definitions state that the planets should be orbiting around either a star or a stellar remanent. What with the satellites? Are they planets or not? The geological and geophysical similarity of the larger satellites with the terrestrial planets shows that both, planets and satellites, are specimens of the same class of objects. In this work it is proposed that the definition of a planet will be made taking into account its geophysical characteristics and no by its position or neighborhood. The threshold mass of nuclear reaction is a physical feature and then it is suitable for the definition. The spherical form is another physical feature that is determinate by the strength of the gravity field and it is not produced in smaller bodies where material cohesion is stronger than gravity and could maintain irregular forms, then the nearly spherical form it is proposed as a criterion to define the minimum mass of the planets. The bodies that until now had been recognized as planets are all differentiated in their interior and this feature is function of the mass since with very small bodies the process of differentiation could not be produced. By all these the definition that here it is proposed is as follows: Planet is a body, no matter how they formed, no matter which is the place or neighborhood it take up, that have a mass below the threshold mass for thermonuclear fusion of deuterium and a mass sufficiently larger to have a spherical form and a differentiated interior both induced gravitationally. This definition includes all the bodies of the Solar System that until now it had been considered as planets. Accepting this definition it could grown the number of planets in our system including some of the new uncovered trans-Neptunian objects like Xena, Sedna and Quaoar (if it is demonstrated that there are spherical and differentiated), and some asteroids like Vesta that have spherical form and seem to be differentiated.

  3. Terrestrial Planet Finder

    NASA Technical Reports Server (NTRS)

    Smith, Andrew

    2004-01-01

    Integrating and testing the proposed Terrestrial Planet Finder imposes constraints on the design. Some of these will be discussed including the dimensions of existing test facilities, the effects of gravity, ambient vibrations and the size of GSE optics.

  4. Planets Around Neutron Stars

    NASA Technical Reports Server (NTRS)

    Wolszczan, Alexander; Kulkarni, Shrinivas R; Anderson, Stuart B.

    2003-01-01

    The objective of this proposal was to continue investigations of neutron star planetary systems in an effort to describe and understand their origin, orbital dynamics, basic physical properties and their relationship to planets around normal stars. This research represents an important element of the process of constraining the physics of planet formation around various types of stars. The research goals of this project included long-term timing measurements of the planets pulsar, PSR B1257+12, to search for more planets around it and to study the dynamics of the whole system, and sensitive searches for millisecond pulsars to detect further examples of old, rapidly spinning neutron stars with planetary systems. The instrumentation used in our project included the 305-m Arecibo antenna with the Penn State Pulsar Machine (PSPM), the 100-m Green Bank Telescope with the Berkeley- Caltech Pulsar Machine (BCPM), and the 100-m Effelsberg and 64-m Parkes telescopes equipped with the observatory supplied backend hardware.

  5. Magnetic Mystery Planets

    NASA Astrophysics Data System (ADS)

    Fillingim, M. O.; Brain, D. A.; Peticolas, L. M.; Yan, D.; Fricke, K. W.; Thrall, L.

    2013-12-01

    The magnetic fields of the large terrestrial planets, Venus, Earth, and Mars, are all vastly different from each other. These differences can tell us a lot about the interior structure, interior history, and even give us clues to the atmospheric history of these planets. This presentation highlights a classroom presentation and accompanying activity that focuses on the differences between the magnetic fields of Venus, Earth, and Mars, what these differences mean, and how we measure these differences. During the activity, students make magnetic field measurements and draw magnetic field lines around "mystery planets" using orbiting "spacecraft" (small compasses). Based on their observations, the students then determine whether they are orbiting Venus-like, Earth-like, or Mars-like planets. This activity is targeted to middle/high school age audiences. However, we also show a scaled-down version that has been used with elementary school age audiences.

  6. Kepler's Multiple Planet Systems

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    2012-01-01

    Among the 1800 Kepler targets that have candidate planets, 20% have two or more candidate planets. While most of these objects have not yet been confirmed as true planets, several considerations strongly suggest that the vast majority of these multi-candidate systems are true planetary systems. Virtually all candidate systems are stable, as tested by numerical integrations (assuming a nominal mass-radius relationship). Statistical studies performed on these candidates reveal a great deal about the architecture of planetary systems, including the typical spacing of orbits and flatness of planetary systems. The distribution of observed period ratios shows that the vast majority of candidate pairs are neither in nor near low-order mean motion resonances. Nonetheless, there are small but statistically significant excesses of candidate pairs both in resonance and spaced slightly too far apart to be in resonance, particularly near the 2:1 resonance. The characteristics of the confirmed Kepler multi-planet systems will also be discussed.

  7. All for the Planet, the Planet for everyone!

    NASA Astrophysics Data System (ADS)

    Drndarski, Marina

    2014-05-01

    The Eco-Musketeers are unique voluntary group of students. They have been established in Belgrade, in Primary school 'Drinka Pavlović'. Since the founding in year 2000, Eco-Musketeers have been involved in peer and citizens education guided by motto: All for the planet, the planet for all! Main goals of this group are spreading and popularization of environmental approach as well as gaining knowledge through collaborative projects and research. A great number of students from other schools in Serbia have joined Eco-Musketeers in observations aiming to better understand the problem of global climate change. In the past several years Eco-Musketeers have also participated in many national and international projects related to the active citizenship and rising the awareness of the importance of biodiversity and environment for sustainable development of society. In this presentation we will show some of the main activities, eco-performances and actions of our organization related to the environment, biodiversity, conservation and recycling, such as: spring cleaning the streets of Belgrade, cleaning the Sava and the Danube river banks, removing insect moth pupae in the area of Lipovica forest near Belgrade. Also, Eco-Musketeers worked on education of employees of Coca-Cola HBC Serbia about energy efficiency. All the time, we have working on raising public awareness of the harmful effects of plastic bags on the environment, too. In order to draw attention on rare and endangered species in Serbia and around the globe, there were several performing street-plays about biodiversity and also the plays about the water ecological footprint. Eco-Musketeers also participated in international projects Greenwave-signs of spring (Fibonacci project), European Schools For A Living Planet (WWF Austria and Erste stiftung) and Eco Schools. The eco dream of Eco-Musketeers is to influence the Government of the Republic of Serbia to determine and declare a 'green habits week'. This should be a one week in a year during which all the citizens will act with a minimum negative impact on the environment. All previous activities of the Eco-Musketeers are the only a small step in a persevering process of conservation of the living world, but we strongly believe that though the activities of small group as we are, we can change the way of thinking of our fellows and citizens, so that they learn to love and protect nature for future generations.

  8. The planet Mercury (1971)

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The physical properties of the planet Mercury, its surface, and atmosphere are presented for space vehicle design criteria. The mass, dimensions, mean density, and orbital and rotational motions are described. The gravity field, magnetic field, electromagnetic radiation, and charged particles in the planet's orbit are discussed. Atmospheric pressure, temperature, and composition data are given along with the surface composition, soil mechanical properties, and topography, and the surface electromagnetic and temperature properties.

  9. Outer planet satellites

    SciTech Connect

    Schenk, P.M. )

    1991-01-01

    Recent findings on the outer-planet satellites are presented, with special consideration given to data on the rheologic properties of ice on icy satellites, the satellite surfaces and exogenic processes, cratering on dead cratered satellites, volcanism, and the interiors of outer-planet satellites. Particular attention is given to the state of Titan's surface and the properties of Triton, Pluto, and Charon. 210 refs.

  10. Transit of Extrasolar Planets

    NASA Technical Reports Server (NTRS)

    Doyle, Laurance R.

    1998-01-01

    During the past five years we have pursued the detection of extrasolar planets by the photometric transit method, i.e. the detection of a planet by watching for a drop in the brightness of the light as it crosses in front of a star. The planetary orbit must cross the line-of-sight and so most systems will not be lined up for such a transit to ever occur. However, we have looked at eclipsing binary systems which are already edge-on. Such systems must be very small in size as this makes the differential light change due to a transit much greater for a given planet size (the brightness difference will be proportional to the area of the transiting planet to the disc area of the star). Also, the planet forming region should be closer to the star as small stars are generally less luminous (that is, if the same thermal regime for planet formation applies as in the solar system). This led to studies of the habitable zone around other stars, as well. Finally, we discovered that our data could be used to detect giant planets without transits as we had been carefully timing the eclipses of the stars (using a GPS antenna for time) and this will drift by being offset by any giant planets orbiting around the system, as well. The best summary of our work may be to just summarize the 21 refereed papers produced during the time of this grant. This will be done is chronological order and in each section separately.

  11. Planets' magnetic environments

    SciTech Connect

    Lanzerotti, L.J.; Uberoi, C.

    1989-02-01

    The magnetospheres of Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and comets and the heliomagnetosphere are examined. The orientations of the planetary spin and magnetic axes, the size of the magnetospheres, and the magnetic properties and the radio emissions of the planets are compared. Results from spacecraft studies of the planets are included. Plans for the Voyager 2 mission and its expected study of the Neptune magnetosphere are considered.

  12. Atmospheres of Jovian Planets

    NASA Astrophysics Data System (ADS)

    Chanover, Nancy

    The giant planets of the solar system have been studied for centuries using a wide range of remote sensing and in situ techniques. An understanding of the atmospheres of Jupiter, Saturn, Uranus, and Neptune has dramatically improved since the dawn of spacecraft exploration of the outer solar system in the 1970s. Cloud decks that were predicted to exist from thermochemical equilibrium arguments have been observationally confirmed, although the exact vertical distribution of condensible species in these atmospheres remains an active area of study. All four of the giant planets have fast zonal (east-west) winds with prograde and retrograde jets, which dominate their atmospheric circulations. Each planet also contains long-lived cyclonic features or convective cloud features that appear and disappear on short timescales. These features suggest a link between the energy transport in the deep atmosphere and the visible cloud tops; the exact nature of this connection remains an outstanding question in giant planet atmosphere studies. The chemistry of the giant planet atmospheres is driven by both the convective processes that loft disequilibrium species from the deep atmosphere into the stratosphere and the interaction between stratospheric materials and ultraviolet sunlight. A unique opportunity to study these interactions was presented to planetary scientists in 1994, when the 22 fragments of Comet Shoemaker-Levy 9 impacted Jupiter. The future of giant planet atmospheric studies is promising. Several mission concepts that will answer fundamental questions regarding giant planet atmospheres are in various stages of development, and the James Webb Space Telescope will also contribute especially to our understanding of Uranus and Neptune. As an understanding of giant planet formation and evolution expands and deepens, these knowledge gains must be examined against the backdrop of the numerous exoplanet systems recently discovered, very few of which resemble our own.

  13. The Gemini Planet Imager

    NASA Astrophysics Data System (ADS)

    Macintosh, Bruce; Graham, J. R.; Palmer, D.; Doyon, R.; Larkin, J.; Oppenheimer, B.; Saddlemyer, L.; Veran, J.; Wallace, J. K.; Gemini Planet Imager Team

    2007-12-01

    Direct detection of extrasolar planets would be a major step in the study of other solar systems, sensitive to planets beyond the period cutoff of Doppler surveys. Furthermore, such planets can be spectrally characterized to measure temperature, gravity, and perhaps composition, shedding light on planet formation and evolution. Surveys of 50-100 young stars with current generation AO systems have excluded the presence of massive (2-10 MJ), young (? Myr) planets in wide (? AU) orbits, but to probe 5-20 AU scales around a large sample of target stars will require dedicated next-generation instruments. One such facility will be the Gemini Planet Imager (GPI). It combines a 2000-actuator adaptive optics system, an apodized-pupil Lyot coronagraph, a precision infrared interferometer for real-time wavefront calibration at the nanometer level, and a near-infrared integral field spectrograph for detection and characterization of the target planets. GPI will be able to achieve Strehl ratios > 0.9 at 1.65 microns and to observe a broad sample of science targets with I band magnitudes less than 9. In addition to planet detection, GPI will also be capable of polarimetric imaging of circumstellar dust disks, studies of evolved stars, and high-Strehl imaging spectroscopy of bright targets - opening up a new field in the characterization of the environments of nearby stars. I will present an overview of the instrument design and its scientific capabilities. GPI is currently in the design phase, scheduled for deployment as a facility instrument on the Gemini South telescope in early 2011. Portions of this work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The Gemini Observatory is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership.

  14. The planet Saturn (1970)

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The present-day knowledge on Saturn and its environment are described for designers of spacecraft which are to encounter and investigate the planet. The discussion includes physical properties of the planet, gravitational field, magnetic and electric fields, electromagnetic radiation, satellites and meteoroids, the ring system, charged particles, atmospheric composition and structure, and clouds and atmospheric motions. The environmental factors which have pertinence to spacecraft design criteria are also discussed.

  15. Astrobiological and Geological Implications of Convective Transport in Icy Outer Planet Satellites

    NASA Technical Reports Server (NTRS)

    Pappalardo, Robert T.; Zhong, Shi-Jie; Barr, Amy

    2005-01-01

    The oceans of large icy outer planet satellites are prime targets in the search for extraterrestrial life in our solar system. The goal of our project has been to develop models of ice convection in order to understand convection as an astrobiologically relevant transport mechanism within icy satellites, especially Europa. These models provide valuable constraints on modes of surface deformation and thus the implications of satellite surface geology for astrobiology, and for planetary protection. Over the term of this project, significant progress has been made in three areas: (1) the initiation of convection in large icy satellites, which we find probably requires tidal heating; (2) the relationship of surface features on Europa to internal ice convection, including the likely role of low-melting-temperature impurities; and (3) the effectiveness of convection as an agent of icy satellite surface-ocean material exchange, which seems most plausible if tidal heating, compositional buoyancy, and solid-state convection work in combination. Descriptions of associated publications include: 3 published papers (including contributions to 1 review chapter), 1 manuscript in revision, 1 manuscript in preparation (currently being completed under separate funding), and 1 published popular article. A myriad of conference abstracts have also been published, and only those from the past year are listed.

  16. Mapping the Red Planet

    NASA Technical Reports Server (NTRS)

    Smith, David E.; Smith, David E.

    2001-01-01

    Since September 1997 the Mars Global Surveyor spacecraft has been orbiting the planet Mars and acquiring new data about the red planet that is changing our view of its present state and past history. Except for a few weeks in October 1997 and a few months in the Spring/Summer of 1998 when special science operations were conducted the spacecraft spent the first 18 months if its time at Mars getting to the right orbital geometry for the mapping mission. But on March 1, 1999 the MGS spacecraft trained its instruments onto the planet to begin a full Mars year (684 Earth days) of continuous systematic mapping and observation of the planet. The camera began wide angle and high resolution mapping, the thermal emission spectrometer began sensing the atmosphere and the material properties of the surface, the magnetometer searched out regions of abnormally high magnetism, the altimeter began determining the precise shape of the planet, and the radio science experiment began determining atmospheric pressures, temperatures and mapping the planet's gravity field. In a matter of a month more data was acquired about

  17. Building a virtual planet

    NASA Technical Reports Server (NTRS)

    Meadows, V. S.

    2002-01-01

    The virtual Planetary Laboratory (VPL) is a recently funded 5-yr project, which seeks toimprove our understanding of the range of plausible environments and the likely signatures for life on extrasolar terrestrial planets. To achieve these goals we are developing a suite of innovative modeling tools to simulate the environments and spectra of extrasolar planets. The core of the VPL IS a coupled radiative transfer/climate/chemistry model, which is augmented by interchangeable modules which characterize geological, exogenic, atmospheric escape, and life processes. The VPL is validated using data derived from terrestrial planets within our own solar system. The VPL will be used to explore the plausible range of atmospheric composittions and globally averaged spectra for extrasolar planets and for early Earth, and will improve our understanding of the effect of life on a planet's atmospheric spectrum and composition. The models will also be used to create a comprehensive spectral catalog to provide recommendations on the optimum wavelength range, spectral resolution, and instrument sensitivity required to characterize extrasolar terrestrial planets. Although developed by our team, the VPL is envisioned to be a comprehensive and flexible tool, which can be collaboratively used by the broader planetary science and astrobiology communities. This presentation will describe the project concept, the tasks involved, and will outline current progress to date. This work is funded by the NASA Astrobiology Institute.

  18. The Atmospheres of Extrasolar Planets

    NASA Technical Reports Server (NTRS)

    Richardson, L. J.; Seager, S.

    2007-01-01

    In this chapter we examine what can be learned about extrasolar planet atmospheres by concentrating on a class of planets that transit their parent stars. As discussed in the previous chapter, one way of detecting an extrasolar planet is by observing the drop in stellar intensity as the planet passes in front of the star. A transit represents a special case in which the geometry of the planetary system is such that the planet s orbit is nearly edge-on as seen from Earth. As we will explore, the transiting planets provide opportunities for detailed follow-up observations that allow physical characterization of extrasolar planets, probing their bulk compositions and atmospheres.

  19. Appearance of high-pressure H2O ice on ice-covered terrestrial planets

    NASA Astrophysics Data System (ADS)

    Ueta, S.; Sasaki, T.

    2014-03-01

    A lot of terrestrial exoplanets and free-floating planets have been discovered. Whether terrestrial planets with liquid water exist is an important question to consider, especially in terms of their habitability. Even in a globally ice-covered state, liquid water could exist beneath the surface ice shell because sufficient geothermal heat flow from the planetary interior is likely to melt the interior ice, so that an internal ocean under the surface ice shell could appear (e.g., Hoffman & Schrag 2002). In this study, we argue the conditions that must be satisfied for ice-covered terrestrial planets to have an internal ocean on the timescale of planetary evolution (Ueta & Sasaki 2013). Geothermal heat flow calculated by a parameterized convection model (e.g., McGovern & Schubert 1989) is considered as the heat source at the origin of the internal ocean. By applying and improving the model of Tajika (2008), we also examine how the amount of radiogenic heat and H2O mass affect these conditions. Moreover, we investigate the structures of surface H2O layers of ice-covered planets by considering the effects of ice under high pressure (high-pressure ice). At 1 AU from the central star, as shown in Fig. 1, a 1M.+ planet with 0.6-25 times H2O mass of the Earth could have an internal ocean. When the planet has an H2O mass over 25 times that of the Earth, high-pressure ice layers may appear between the internal ocean and the rock-part of the planet. The results indicate that planetary size and surface H2O mass strongly ristrict the conditions under which an extrasolar terrestrial planet could have an internal ocean without high-pressure ice existing under the internal ocean. The habitability of a planet might be influenced by the existence of such high-pressure ice layers.

  20. Extrasolar binary planets. I. Formation by tidal capture during planet-planet scattering

    SciTech Connect

    Ochiai, H.; Nagasawa, M.; Ida, S.

    2014-08-01

    We have investigated (1) the formation of gravitationally bounded pairs of gas-giant planets (which we call 'binary planets') from capturing each other through planet-planet dynamical tide during their close encounters and (2) the subsequent long-term orbital evolution due to planet-planet and planet-star quasi-static tides. For the initial evolution in phase 1, we carried out N-body simulations of the systems consisting of three Jupiter-mass planets taking into account the dynamical tide. The formation rate of the binary planets is as much as 10% of the systems that undergo orbital crossing, and this fraction is almost independent of the initial stellarcentric semimajor axes of the planets, while ejection and merging rates sensitively depend on the semimajor axes. As a result of circularization by the planet-planet dynamical tide, typical binary separations are a few times the sum of the physical radii of the planets. After the orbital circularization, the evolution of the binary system is governed by long-term quasi-static tide. We analytically calculated the quasi-static tidal evolution in phase 2. The binary planets first enter the spin-orbit synchronous state by the planet-planet tide. The planet-star tide removes angular momentum of the binary motion, eventually resulting in a collision between the planets. However, we found that the binary planets survive the tidal decay for the main-sequence lifetime of solar-type stars (∼10 Gyr), if the binary planets are beyond ∼0.3 AU from the central stars. These results suggest that the binary planets can be detected by transit observations at ≳ 0.3 AU.

  1. Archaeoastronomical Concepts in Popular Culture

    NASA Astrophysics Data System (ADS)

    Krupp, Edwin C.

    Broad public embrace of archaic astronomy probably began in the eighteenth century with awareness of the summer solstice sunrise's affiliation with Stonehenge. Since that time, Stonehenge has retained an astronomical mystique that attracts crowds mobilized by the monument's supposed cosmic purpose. They are committed to witness prehistoric heritage operating in real time and with enduring function. More recently, mass media have intermittently thrown a spotlight on new archaeoastronomical discoveries. While the details, ambiguities, and nuances of disciplined study of astronomy in antiquity do not usually infiltrate popular culture, some astronomical alignments, celestial events, sky-tempered symbols, and astral narratives have become well known and referenced in popular culture. Places and relics that command public interest with astronomical connotations are transformed into cultural icons and capture visitors on a quest for the authenticity the past is believed to possess. Monuments and ideas that successfully forge a romantic bond with the past and inspire an imagined sense of sharing the experience, perspective, and wisdom of antiquity persist in the cultural landscape.

  2. Noninsect Arthropods in Popular Music.

    PubMed

    Coelho, Joseph R

    2011-01-01

    The occurrence of noninsect arthropods in popular music was examined in order to explore human attitudes toward these species, especially as compared to insects. Crustaceans were the most commonly referenced taxonomic group in artist names, album titles and cover art, followed by spiders and scorpions. The surprising prevalence of crustaceans may be related to the palatability of many of the species. Spiders and scorpions were primarily used for shock value, as well as totemic qualities of strength and ferocity. Spiders were the most abundant group among song titles, perhaps because of their familiarity to the general public. Three noninsect arthropod album titles were found from the early 1970s, then none appear until 1990. Older albums are difficult to find unless they are quite popular, and the resurgence of albums coincides with the rise of the internet. After 1990, issuance of such albums increased approximately linearly. Giant and chimeric album covers were the most common of themes, indicating the use of these animals to inspire fear and surprise. The lyrics of select songs are presented to illustrate the diversity of sentiments present, from camp spookiness to edibility. PMID:26467627

  3. Noninsect Arthropods in Popular Music

    PubMed Central

    Coelho, Joseph R.

    2011-01-01

    The occurrence of noninsect arthropods in popular music was examined in order to explore human attitudes toward these species, especially as compared to insects. Crustaceans were the most commonly referenced taxonomic group in artist names, album titles and cover art, followed by spiders and scorpions. The surprising prevalence of crustaceans may be related to the palatability of many of the species. Spiders and scorpions were primarily used for shock value, as well as totemic qualities of strength and ferocity. Spiders were the most abundant group among song titles, perhaps because of their familiarity to the general public. Three noninsect arthropod album titles were found from the early 1970s, then none appear until 1990. Older albums are difficult to find unless they are quite popular, and the resurgence of albums coincides with the rise of the internet. After 1990, issuance of such albums increased approximately linearly. Giant and chimeric album covers were the most common of themes, indicating the use of these animals to inspire fear and surprise. The lyrics of select songs are presented to illustrate the diversity of sentiments present, from camp spookiness to edibility. PMID:26467627

  4. Climate model studies of synchronously rotating planets.

    PubMed

    Joshi, Manoj

    2003-01-01

    M stars constitute 75% of main sequence stars though, until recently, their star systems have not been considered suitable places for habitable planets to exist. In this study the climate of a synchronously rotating planet around an M dwarf star is evaluated using a three-dimensional global atmospheric circulation model. The presence of clouds and evaporative cooling at the surface of the planet result in a cooler surface temperature at the subsolar point. Water ice forms at the polar regions and on the dark side, where the minimum temperature lies between -30 degrees C and 0 degrees C. As expected, rainfall is extremely high on the starlit side and extremely low on the dark side. The presence of a dry continent causes higher temperatures on the dayside, and allows accumulation of snow on the nightside. The absence of any oceans leads to higher day-night temperature differences, consistent with previous work. The present study reinforces recent conclusions that synchronously rotating planets within the circumstellar habitable zones of M dwarf stars should be habitable, and therefore M dwarf systems should not be excluded in future searches for exoplanets. PMID:14577888

  5. Eccentricities of Extrasolar Planets and Implications for Planet Formation Theory

    NASA Astrophysics Data System (ADS)

    Ford, Eric B.

    2006-12-01

    The discovery of 200 extrasolar planets around solar-like stars has revealed an unexpected diversity of planets that continues to challenge theories of planet formation. In particular, most known extrasolar planets have significant eccentricities, including many massive giant planets. In this poster, we present a Bayesian analysis of the radial velocity observations taken by the California and Carnegie Planet Search at Keck and recently published by Butler et al. (2006). We investigate the observational constraints for the eccentricity distribution of giant extrasolar planets and discuss the implications for theories of planet formation. We outline how future radial velocity observations can test models of planet formation. Support for E.B.F. was provided by NASA through Hubble Fellowship grant HST-HF-01195.01A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS 5-26555.

  6. Importance and Perspectives of the Earth Sciences Popularization in Mexico

    NASA Astrophysics Data System (ADS)

    Flores-Estrella, H.; Yussim, S.

    2007-05-01

    In our days the scientific popularization in Mexico has not a promising future and with the earth sciences is not better; most of the papers in the popularization magazines deal with subjects as earthquakes, volcanoes, plate tectonics, meteorite impacts and the massive extensions associated with them (e.g. Chicxulub). However, these subjects have not been enough to create conscience about the importance of earth sciences in the society and it has even motivated the idea of a community distant scientific with no social obligation, the idea that the earth scientists are responsible for all the problems in the planet (global warming, catastrophes) is wide spread. In these days that we need a change in our consumption, mainly in the energetic one, it's compulsory to change the relation between the subject and its environment; then, as we can not take care of something that we don't know, the scientific popularization has a fundamental role that we must start to pay attention to.

  7. Protostars and Planets VI

    NASA Astrophysics Data System (ADS)

    Beuther, Henrik; Klessen, Ralf S.; Dullemond, Cornelis P.; Henning, Thomas

    The Protostars and Planets book and conference series has been a long-standing tradition that commenced with the first meeting led by Tom Gehrels and held in Tucson, Arizona, in 1978. The goal then, as it still is today, was to bridge the gap between the fields of star and planet formation as well as the investigation of planetary systems and planets. As Tom Gehrels stated in the preface to the first Protostars and Planets book, "Cross-fertilization of information and understanding is bound to occur when investigators who are familiar with the stellar and interstellar phases meet with those who study the early phases of solar system formation." The central goal remained the same for the subsequent editions of the books and conferences Protostars and Planets II in 1984, Protostars and Planets III in 1990, Protostars and Planets IV in 1998, and Protostars and Planets V in 2005, but has now been greatly expanded by the flood of new discoveries in the field of exoplanet science. The original concept of the Protostars and Planets series also formed the basis for the sixth conference in the series, which took place on July 15-20, 2013. It was held for the first time outside of the United States in the bustling university town of Heidelberg, Germany. The meeting attracted 852 participants from 32 countries, and was centered around 38 review talks and more than 600 posters. The review talks were expanded to form the 38 chapters of this book, written by a total of 250 contributing authors. This Protostars and Planets volume reflects the current state-of-the-art in star and planet formation, and tightly connects the fields with each other. It is structured into four sections covering key aspects of molecular cloud and star formation, disk formation and evolution, planetary systems, and astrophysical conditions for life. All poster presentations from the conference can be found at www.ppvi.org. In the eight years that have passed since the fifth conference and book in the Protostars and Planets series, the field of star and planet formation has progressed enormously. The advent of new space observatories like Spitzer and more recently Herschel have opened entirely new windows to study the interstellar medium, the birthplaces of new stars, and the properties of protoplanetary disks. Millimeter and radio observatories, in particular interferometers, allow us to investigate even the most deeply embedded and youngest protostars. Complementary to these observational achievements, novel multi-scale and multi-physics theoretical and numerical models have provided new insights into the physical and chemical processes that govern the birth of stars and their planetary systems. Sophisticated radiative transfer modeling is critical in order to better connect theories with observations. Since the last Protostars and Planets volume, more than 1000 new extrasolar planets have been identified and there are thousands more waiting to be verified. Such a large database allows for the first time a statistical assessment of the planetary properties as well as their evolution pathways. These investigations show the enormous diversity of the architecture of planetary systems and the properties of planets. High-contrast imaging at short and long wavelengths has resolved protoplanetary disks and associated planets, and transit spectroscopy is a new tool that allows us to study even the physical properties of extrasolar planetary atmospheres. The understanding of our own solar system has also progressed enormously since 2005. For instance, the sample-return Stardust mission has provided direct insight into the composition of comets and asteroids, and has demonstrated the importance of mixing processes in the early solar system. And much more is now known about the origin and role of short-lived nuclides at these stages of the solar system. For generations of astronomers, the Protostars and Planets volumes have served as an essential resource for our understanding of star and planet formation. They are used by students to dive into new topics, and they are much valued by experienced researchers as a comprehensive overview of the field with all its interactions. We hope that you will enjoy reading (and learning from) this book as much as we do. The organization of the Protostars and Planets conference was carried out in close collaboration between the Max Planck Institute for Astronomy and the Center for Astronomy of the University Heidelberg, with generous support from the German Science Foundation. This volume is a product of effort and care by many people. First and foremost, we want to acknowledge the 250 contributing authors, as it is only due to their expertise and knowledge that such a comprehensive review compendium in all its depth and breadth is possible. The Protostars and Planets VI conference and this volume was a major undertaking, with support and contributions by many people and institutions. We like to thank the members of the Scientific Advisory Committee who selected the 38 teams and chapters out of more than 120 submitted proposals. Similarly, we are grateful to the reviewers, who provided valuable input and help to the chapter authors. The book would also not have been possible without the great support of Renée Dotson and other staff from USRA’s Lunar and Planetary Institute, who handled the detailed processing of all manuscripts and the production of the book, and of Allyson Carter and other staff from the University of Arizona Press. We are also grateful to Richard Binzel, the General Editor of the Space Science Series, for his constant support during the long process, from the original concept to this final product. Finally, we would like to express a very special thank you to the entire conference local organizing committee, and in particular, Carmen Cuevas and Natali Jurina, for their great commitment to the project and for a very fruitful and enjoyable collaboration.

  8. Was There Really a Popular Science "Boom"?

    ERIC Educational Resources Information Center

    Lewenstein, Bruce V.

    1987-01-01

    Traces the major developments and trends in contemporary popular science. Identifies magazines, television shows, and newspaper sections devoted to popular science and discusses their status and impact. Comments on the rise, fall, and future of the "science boom." (ML)

  9. Identifying Obstacles to Incorporating Ocean Content into California Secondary Classrooms

    ERIC Educational Resources Information Center

    Stock, Jennifer

    2010-01-01

    The ocean is the dominant feature on this planet that makes all life on Earth possible. Marine educators and scientists across the country have identified essential principles and concepts that define what an "ocean literate" person should know, but there is a lack of comprehensive ocean content coverage in secondary classrooms across the United…

  10. Spanish Federation of Popular Universities (FEUP)

    ERIC Educational Resources Information Center

    Serrano, Isabel Garcia-Longoria

    2006-01-01

    This article features the Spanish Popular Universities, which are defined as "a project of cultural development that acts in the municipality, whose objective is to promote social participation, education, training, and culture in order to improve life quality" (Federation of Popular Education Universities, 2000). A century of history of Popular

  11. Mass Media and the Popular Arts.

    ERIC Educational Resources Information Center

    Rissover, Fredric; Birch, David C.

    This anthology consists of journalistic essays on each of these popular arts: advertising, journalism, cartoons, radio and television, photography and motion pictures, popular literature, popular music, and public education. Examples of most of the art forms are also included. The book is aimed at junior college students. Its purpose is to…

  12. A Study of Egocentrism and Popularity

    ERIC Educational Resources Information Center

    Karmos, Joseph S.; Milcic, Diane

    1978-01-01

    Investigates egocentrism and the relationship between egocentrism and popularity in grades 1 through 5. Teachers' ability to rate students' popularity was studied, and sex differences for egocentrism scores were also examined. Egocentrism was measured by a test based on work done by Jean Piaget and popularity defined by a teacher's rating scale…

  13. The Popularity of Middle School Bullies

    ERIC Educational Resources Information Center

    Thunfors, Peter; Cornell, Dewey

    2008-01-01

    This study investigated the peer popularity of middle school students involved in bullying. Bullying was assessed by peer report using the School Climate Bullying Survey (SCBS) and popularity was assessed through peer nominations from a student roster. In a sample of 379 middle school students, bullies were among the most popular students in the…

  14. History of America: A Popular Music Approach.

    ERIC Educational Resources Information Center

    Chilcoat, George W.

    The study of popular music can be an effective method of examining social and cultural life. Popular music emphasizes the variety of human existence, goals, outlooks, and biases. A pervading theme in popular American music between 1959 and 1984 has been the theme of "America." Over 200 songs reflect personal, social, and political concerns about…

  15. Popular Culture in the Junior College Library

    ERIC Educational Resources Information Center

    Lonergan, David; Ayers, Meredith

    2015-01-01

    Popular culture is extremely influential in both academe and society at large. However, formal disciplinary study of popular culture lags far behind that influence. Anthropology, film studies, history, musicology, and sociology are only some of the disciplines that frequently include popular culture as a research focus. This article advises on how…

  16. Mass Media and the Popular Arts.

    ERIC Educational Resources Information Center

    Rissover, Fredric; Birch, David C.

    This anthology consists of journalistic essays on each of these popular arts: advertising, journalism, cartoons, radio and television, photography and motion pictures, popular literature, popular music, and public education. Examples of most of the art forms are also included. The book is aimed at junior college students. Its purpose is to

  17. Popular Music Pedagogy: Peer Learning in Practice

    ERIC Educational Resources Information Center

    Lebler, Don

    2008-01-01

    The inclusion of popular music as a content area in music education is not uncommon. The musicological study of popular music is well established in higher education, and even the practice of popular music is becoming more common in both secondary education and the post-compulsory sector. However, when this occurs, it is likely to be taught in…

  18. EIT and the Popular Imagination

    NASA Technical Reports Server (NTRS)

    Gurman, J. B.

    2005-01-01

    The Extreme ultraviolet Imaging Telescope on board SOHO, designed and built by Principal Investigator Jean-Pierre Delaboudiniere and his French/Belgan/US team, has produced numerous scientific breakthroughs, and has become both the standard coronal finder telescope and the determinant of whether halo coronal mass ejections are earthward-directed. Due to the dramatic nature of the images produced by EIT over the last nearly ten years, those images have been adopted worldwide in a manner no one could have foreseen before the launch of SOHO. I examine a small sample of the many scientific, commercial, and cultural uses of EIT imagery from the last decade in order to demonstrate how well-visualized, scientific imagery can first penetrate and then become an accepted part of the popular imagination.

  19. Communicating meteorology through popular music

    NASA Astrophysics Data System (ADS)

    Brown, Sally; Aplin, Karen; Jenkins, Katie; Mander, Sarah; Walsh, Claire; Williams, Paul

    2015-04-01

    Previous studies of weather-inspired classical music showed that all forms of music (as well as visual arts and literature) reflect the significance of the environment in society. Here we quantify the extent to which weather has inspired popular musicians, and how weather is represented in English-language pop music. Our work is in press at Weather. Over 750 songs have been identified which were found to refer to meteorological phenomena, mainly in their lyrics, but also in the title of the song, name of the band or songwriter and occasionally in the song's music or sound effects. Over one third of the songs analysed referred to either sun or rain, out of a possible 20 weather categories. It was found that artists use weather to describe emotion, for example, to mirror the changes in a relationship. In this context, rain was broadly seen negatively, and might be used to signify the end of a relationship. Rain could also be perceived in a positive way, such as in songs from more agricultural communities. Wind was the next most common weather phenomenon, but did not represent emotions as much as sun or rain. However, it was the most frequently represented weather type in the music itself, such as in instrumental effects, or non-verbally in choruses. From the limited evidence available, we found that artists were often inspired by a single weather event in writing lyrics, whereas the outcomes were less clearly identifiable from longer periods of good or bad weather. Some artists were influenced more by their environment than others, but they were often inspired to write many songs about their surroundings as part of every-day life, rather than weather in particular. Popular singers and songwriters can therefore emotionally connect their listeners to the environment; this could be exploited to communicate environmental science to a broad audience.

  20. Remote Sensing of Ocean Color

    NASA Astrophysics Data System (ADS)

    Dierssen, Heidi M.; Randolph, Kaylan

    The oceans cover over 70% of the earth's surface and the life inhabiting the oceans play an important role in shaping the earth's climate. Phytoplankton, the microscopic organisms in the surface ocean, are responsible for half of the photosynthesis on the planet. These organisms at the base of the food web take up light and carbon dioxide and fix carbon into biological structures releasing oxygen. Estimating the amount of microscopic phytoplankton and their associated primary productivity over the vast expanses of the ocean is extremely challenging from ships. However, as phytoplankton take up light for photosynthesis, they change the color of the surface ocean from blue to green. Such shifts in ocean color can be measured from sensors placed high above the sea on satellites or aircraft and is called "ocean color remote sensing." In open ocean waters, the ocean color is predominantly driven by the phytoplankton concentration and ocean color remote sensing has been used to estimate the amount of chlorophyll a, the primary light-absorbing pigment in all phytoplankton. For the last few decades, satellite data have been used to estimate large-scale patterns of chlorophyll and to model primary productivity across the global ocean from daily to interannual timescales. Such global estimates of chlorophyll and primary productivity have been integrated into climate models and illustrate the important feedbacks between ocean life and global climate processes. In coastal and estuarine systems, ocean color is significantly influenced by other light-absorbing and light-scattering components besides phytoplankton. New approaches have been developed to evaluate the ocean color in relationship to colored dissolved organic matter, suspended sediments, and even to characterize the bathymetry and composition of the seafloor in optically shallow waters. Ocean color measurements are increasingly being used for environmental monitoring of harmful algal blooms, critical coastal habitats (e.g., seagrasses, kelps), eutrophication processes, oil spills, and a variety of hazards in the coastal zone.

  1. The Role of Giant Planets in Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    Levison, H.; Dones, L.; Agnor, C.; Canup, R.; Duncan, M.

    2001-11-01

    The dynamical structure of the giant planets can play an important role in determining the sizes, numbers, and general habitability of the terrestrial planets. Here we present a progress report of a continuing study of the coupling between outer planetary system architecture and inner planetary system formation. We have studied the growth of terrestrial planets in 6 different outer planetary systems: i) no giant planets, ii) the Solar System's outer planets, iii) a system with giant planets more massive than the Solar System, iv) a system with 7 Uranus-mass planets, v) a system with three Saturn-mass objects on orbits with eccentricities between 0.1 and 0.25, and vi) a system with one Jupiter with an eccentricity of 0.8. The last four systems are taken from our synthetic giant planet systems in Levison et al. (1998; AJ, 116, 1998). We find that the structure of the resulting terrestrial planet system is usually the result of how effectively the terrestrial planet embryos are dynamically excited. The more excited the embryos become, the fewer terrestrial planets form, the more massive these planets are, and the closer they are to the central star. In highly-perturbed systems, we typically find that one ~ 2 M⊕ terrestrial planet forms, which is probably too close to the star to be habitable. (Note that we did not include fragmentation in these simulations, which could be important in these extreme cases.) However, in many of the systems we studied, including our own giant planet system, the principal cause of excitation at 1AU was the self-gravity of the embryos rather than outer planet excitation. In these cases, the giant planets do not seem to play an important role in the formation of terrestrial planets in the habitable zone. This research is supported by NASA's Exobiology Program.

  2. Brown dwarfs and planets.

    NASA Astrophysics Data System (ADS)

    Bonnefoy, M.; Chauvin, G.

    The connection between brown-dwarfs and planets and the definition of giant planets themselves have been a matter of debate for more than a decade now. We summarize our current understanding of their respective formation mechanisms and associated physical properties. We then address the question of planetary formation around brown-dwarfs. Signs of disk evolution (accretion, outflows, grain growth) for young brown-dwarfs suggest that planetary formation may be on-going in the substellar regime. In this context, we report recent results of surveys targeting brown-dwarfs and very low mass stars to search for planetary mass companions and ultimately planets, using various observing techniques (imaging, radial velocity, microlensing, and astrometry). We also highlight the technical and observational challenges of observing such faint targets. Finally, we conclude with the perspectives offered by the new generation of telescopes and instruments in the coming years.

  3. Commission 53: Extrasolar Planets

    NASA Astrophysics Data System (ADS)

    Boss, Alan; Lecavelier des Etangs, Alain; Mayor, Michel; Bodenheimer, Peter; Collier-Cameron, Andrew; Kokubo, Eiichiro; Mardling, Rosemary; Minniti, Dante; Queloz, Didier

    2012-04-01

    Commission 53 was created at the 2006 Prague General Assembly (GA) of the IAU, in recognition of the outburst of astronomical progress in the field of extrasolar planet discovery, characterization, and theoretical work that has occurred since the discovery of the first planet in orbit around a solar-type star in 1995. Commission 53 is the logical successor to the IAU Working Group on Extrasolar Planets (WGESP), which ended its six years of existence in August 2006. The founding President of Commission 53 was Michael Mayor, in honor of his seminal contributions to this new field of astronomy. The current President is Alan Boss, the former chair of the WGESP. The current members of the Commission 53 (C53) Organizing Committee (OC) began their service in August 2009 at the conclusion of the Rio de Janeiro IAU GA.

  4. Magnetic Mystery Planets

    NASA Astrophysics Data System (ADS)

    Fillingim, M.; Brain, D.; Peticolas, L.; Yan, D.; Fricke, K.; Thrall, L.

    2014-07-01

    The magnetic fields of the large terrestrial planets, Venus, Earth, and Mars, are all vastly different from each other. These differences can tell us a lot about the interior structure, interior history, and they can even give us clues to the atmospheric history of these planets. This paper highlights a classroom presentation and accompanying activity that focuses on the differences between the magnetic fields of Venus, Earth, and Mars, what these differences mean, and how we measure these differences. During the activity, students make magnetic field measurements and draw magnetic field lines of “mystery planets” using orbiting “spacecraft” (small compasses). Based on their observations, the students then determine whether they are orbiting Venus-like, Earth-like, or Mars-like planets. This activity is targeted to middle and high school audiences. However, we have also used a scaled-down version with elementary school audiences.

  5. Planetesimals and Planet Formation

    NASA Astrophysics Data System (ADS)

    Chambers, John

    The first step in the standard model for planet formation is the growth of gravitationally bound bodies called ``planetesimals'' from dust grains in a protoplanetary disk. Currently, we do not know how planetesimals form, how long they take to form, or what their sizes and mechanical properties are. The goal of this proposal is to assess how these uncertainties affect subsequent stages of planetary growth and the kind of planetary systems that form. The work will address three particular questions: (i) Can the properties of small body populations in the modern Solar System constrain the properties of planetesimals? (ii) How do the properties of planetesimals affect the formation of giant planets? (iii) How does the presence of a water ice condensation front (the ``snow line'') in a disk affect planetesimal formation and the later stages of planetary growth? These questions will be examined with computer simulations of planet formation using new computer codes to be developed as part of the proposal. The first question will be addressed using a statistical model for planetesimal coagulation and fragmentation. This code will be merged with the proposer's Mercury N-body integrator code to model the dynamics of large protoplanets in order to address the second question. Finally, a self- consistent model of disk evolution and the radial transport of water ice and vapour will be added to examine the third question. A theoretical understanding of how planets form is one of the key goals of NASA and the Origins of Solar Systems programme. Researchers have carried out many studies designed to address this goal, but the questions of how planetesimals form and how their properties affect planet formation have received relatively little attention. The proposed work will help address these unsolved questions, and place other research in context by assessing the importance of planetesimal origins and properties for planet formation.

  6. THE STRUCTURE OF SURFACE H{sub 2}O LAYERS OF ICE-COVERED PLANETS WITH HIGH-PRESSURE ICE

    SciTech Connect

    Ueta, S.; Sasaki, T. E-mail: takanori@geo.titech.ac.jp

    2013-10-01

    Many extrasolar (bound) terrestrial planets and free-floating (unbound) planets have been discovered. While the existence of bound and unbound terrestrial planets with liquid water is an important question, of particular importance is the question of these planets' habitability. Even for a globally ice-covered planet, geothermal heat from the planetary interior may melt the interior ice, creating an internal ocean covered by an ice shell. In this paper, we discuss the conditions that terrestrial planets must satisfy for such an internal ocean to exist on the timescale of planetary evolution. The question is addressed in terms of planetary mass, distance from a central star, water abundance, and abundance of radiogenic heat sources. In addition, we investigate the structure of the surface H{sub 2}O layers of ice-covered planets by considering the effects of ice under high pressure (high-pressure ice). As a fiducial case, a 1 M{sub ⊕} planet at 1 AU from its central star and with 0.6-25 times the H{sub 2}O mass of the Earth could have an internal ocean. We find that high-pressure ice layers may appear between the internal ocean and the rock portion on a planet with an H{sub 2}O mass over 25 times that of the Earth. The planetary mass and abundance of surface water strongly restrict the conditions under which an extrasolar terrestrial planet may have an internal ocean with no high-pressure ice under the ocean. Such high-pressure ice layers underlying the internal ocean are likely to affect the habitability of the planet.

  7. Atmospheric models for post- giant impact planets

    NASA Astrophysics Data System (ADS)

    Lupu, R.; Zahnle, K. J.; Marley, M. S.; Schaefer, L. K.; Fegley, B.; Morley, C.; Cahoy, K.; Freedman, R. S.; Fortney, J. J.

    2013-12-01

    The final assembly of terrestrial planets is now universally thought to have occurred through a series of giant impacts, such as Earth's own Moon-forming impact. These collisions take place over a time interval of about 100 million years, during which time it takes at least 10 collisions between planets to make a Venus or an Earth. In the aftermath of one of these collisions the surviving planet is hot, and can remain hot for millions of years. During this phase of accretion, the proto-terrestrial planet may have a dense steam atmosphere, that will affect both the cooling of the planet and our ability to detect it. Here we explore the atmospheric chemistry, photochemistry, and spectral signatures of post-giant-impact terrestrial planets enveloped by thick atmospheres consisting of vaporized rock material. The atmospheric chemistry is computed self-consistently for atmospheres in equilibrium with hot surfaces, with compositions reflecting either the bulk silicate Earth (BSE, which includes the crust, mantle, atmosphere and oceans) or Earth's continental crust (CC). These two cases allow us to examine differences in atmospheres formed by outgassing of silica-rich (felsic) rocks - like the Earth's continental crust - and MgO- and FeO-rich (mafic) rocks - like the BSE. Studies of detrital zircons from Jack Hills, Australia, show that the continental crust existed 164 million years after the formation of the solar system, in which case the material vaporized in a giant impact should likely reflect the CC composition. However, if at the time of impact the surface of the planet does not yet exhibit the formation of continents, then the BSE case becomes relevant. We compute atmospheric profiles for surface temperatures ranging from 1000 to 2200 K, surface pressures of 10 and 100 bar, and surface gravities of 10 and 30 m/s^2. We account for all major molecular and atomic opacity sources, including collision-induced absorption, to derive the atmospheric structure and compute the reflected and emergent flux. We find that these atmospheres are dominated by H2O and CO2, while the formation of CH4, and NH3 is quenched due to short dynamical timescales. Other important constituents are HF, HCl, NaCl, and SO2. These are apparent in the emerging spectra, and can be indicative that an impact has occurred. Estimates including photochemistry and vertical mixing show that these atmospheres are enhanced in sulfur-bearing species, particularly SO2, one of the most important absorbers. At this stage we do not address cloud formation and aerosol opacity. Estimated luminosities for post-impact planets, although lower than predicted by previous models, show that the hottest post-giant-impact planets will be detectable with the planned 30 m-class telescopes. Finally, we use the models to describe the cooling of a post-impact terrestrial planet and briefly investigate its time evolution, which ends as the planet transitions into a more conventional steam atmosphere runaway greenhouse. This calculation brings a significant improvement over previous runaway greenhouse models, by including additional opacity sources and comprehensive line lists for H2O and CO2. We find that the cooling timescale for post-giant impact Earths ranges between about 10^5 and 10^6 years, where the slower cooling is associated with the planet going through a runaway greenhouse stage.

  8. Location of Planet X

    SciTech Connect

    Harrington, R.S.

    1988-10-01

    Observed positions of Uranus and Neptune along with residuals in right ascension and declination are used to constrain the location of a postulated tenth planet. The residuals are converted into residuals in ecliptic longitude and latitude. The results are then combined into seasonal normal points, producing average geocentric residuals spaced slightly more than a year apart that are assumed to represent the equivalent heliocentric average residuals for the observed oppositions. Such a planet is found to most likely reside in the region of Scorpius, with considerably less likelihood that it is in Taurus. 8 references.

  9. Heat Pipe Planets

    NASA Technical Reports Server (NTRS)

    Moore, William B.; Simon, Justin I.; Webb, A. Alexander G.

    2014-01-01

    When volcanism dominates heat transport, a terrestrial body enters a heat-pipe mode, in which hot magma moves through the lithosphere in narrow channels. Even at high heat flow, a heat-pipe planet develops a thick, cold, downwards-advecting lithosphere dominated by (ultra-)mafic flows and contractional deformation at the surface. Heat-pipes are an important feature of terrestrial planets at high heat flow, as illustrated by Io. Evidence for their operation early in Earth's history suggests that all terrestrial bodies should experience an episode of heat-pipe cooling early in their histories.

  10. Planets and satellites: tectonic twins

    NASA Astrophysics Data System (ADS)

    Kochemasov, G. G.

    2015-10-01

    There are only three solid planet-satellite pairs in the Solar system: Earth -Moon, Mars -Phobos, Pluto - Charon. For the first two pairs tectonic analogies were shown and explained by moving them in one circumsolar orbit. As it is known from the wave planetology [3, 4, 6], "orbits make structures". For the third pair the same was stated as a prediction based on this fundamental rule. Global tectonic forms of wave origin appear in cosmic bodies because they move in keplerian orbits with periodically changing accelerations. Warping bodies waves have a stationary character and obeying wave harmonics lengths. Starting from the fundamental 2πR-long wave 1 making the ubiquitous tectonic dichotomy (two-face appearance) warping wave lengths descend along harmonics. Very prominent along with the wave 1 are waves 2 responsible for tectonic sectoring superimposed on the wave 1 segments. Practically all bodies have traces of shorter waves making numerous polygons (rings) often confused with impact craters. Earth and the Moon moving in one circumsolar orbit both are distorted by wave 1, wave 2 and wave 4 features aligned along extent tectonic lines [4, 5]. At Earth they are: Pacific Ocean (2πR-structure) and Indian Ocean (πR-structure) from both ends with Malay Archipelago (πR/4-structure) in the middle. At Moon they are: Procellarum Ocean (2πR) and SPA Basin (πR) from ends and Mare Orientale (πR/4) in the middle. A regular disposition is surprising. Both Oceans and Basin occur on opposite hemispheres, lying in the middle both ring structures occur in the boundary between two hemispheres and are of the same relative size. These triads stretch along lines parallel to the equator (Earth) and with the angle about 30 degrees to it (Moon) indicating at a different orientation of the rotation axes in the ancient time [2]. On the whole, one could speak about a "lunar mould" of Earth [5] (Fig. 1-3). Another tectonic twin is the pair Mars -Phobos. Both bodies sharing one circumsolar orbit, twice as long as the Earth -Moon orbit, acquire slightly oblong ellipsoidal shape (Fig. 4, 5). Very pronounced on both so much different in size and composition bodies the deepest basins - Hellas and Stickney (sectoral πR-structures) are comparable features. The structural unity is predicted also for the third solid body pair -Pluto -Charon.

  11. Toward Predicting Popularity of Social Marketing Messages

    NASA Astrophysics Data System (ADS)

    Yu, Bei; Chen, Miao; Kwok, Linchi

    Popularity of social marketing messages indicates the effectiveness of the corresponding marketing strategies. This research aims to discover the characteristics of social marketing messages that contribute to different level of popularity. Using messages posted by a sample of restaurants on Facebook as a case study, we measured the message popularity by the number of "likes" voted by fans, and examined the relationship between the message popularity and two properties of the messages: (1) content, and (2) media type. Combining a number of text mining and statistics methods, we have discovered some interesting patterns correlated to "more popular" and "less popular" social marketing messages. This work lays foundation for building computational models to predict the popularity of social marketing messages in the future.

  12. Experimental determination of salt partition coefficients between aqueous fluids, ice VI and ice VII: implication for the composition of the deep ocean and the geodynamics of large icy moons and water rich planets

    NASA Astrophysics Data System (ADS)

    Journaux, Baptiste; Daniel, Isabelle; Cardon, Hervé; Petitgirard, Sylvain; Perrillat, Jean-Philippe; Caracas, Razvan; Mezouar, Mohamed

    2015-04-01

    The potential habitability of extraterrestrial large aqueous reservoir in icy moons and exoplanets requires an input of nutrients and chemicals that may come from the rocky part of planetary body. Because of the presence of high pressure (HP) water ices (VI, VII, etc.) between the liquid ocean and the silicates, such interactions are considered to be limited in large icy moons, like Ganymede and Titan, and water rich exoplanets. In the case of salty-rich oceans, recent experimental and modeling works have shown that aqueous fluids can be stable at higher pressures [1, 2]. This can ultimately allow direct interaction with the rocky core of icy moons. This effect is nevertheless limited and for larger bodies such as water rich exoplanets with much higher pressures in their hydrosphere, HP ice should be present between the rocky core and a putative ocean. Salts are highly incompatible with low pressure ice Ih, but recent experimental work has shown that alkali metal and halogen salts are moderately incompatible with ice VII, that can incorporate up to several mol/kg of salts [3, 4, 5]. As far as we know, no similar study has been done on ice VI, a HP ice phase expected inside large icy moons. We present here the first experimental data on the partition coefficient of RbI salt between aqueous fluids, ice VI and ice VII using in-situ synchrotron X-Ray single crystal diffraction and X-Ray fluorescence mapping (ESRF - ID-27 beam line [6]). Our experiment enable us to observe a density inversion between ice VI and the salty fluid, and to measure the values of salt partition coefficients between the aqueous fluid and ice VI (strongly incompatible) and ice VII (moderately incompatible). Using the volumes determined with X-Ray diffraction, we were able to measure the density of salty ice VI and ice VII and determine that salty ice VI is lighter than pure H2O ice VI. These results are very relevant for the study of water rich planetary bodies interior because the partition coefficient will enable the computation of the chemical evolution in the deep ocean during the cooling of the hydrosphere. These results are also very important for the high pressure ice mantle dynamics as they show the great effects of dissolved salt on the ice phases densities and therefore the potential role of convecting ice to feed the overlaying ocean with life-sustaining chemicals. References [1] Journaux B, Daniel I, Caracas R, Montagnac G, Cardon H. Icarus. 2013; 226:35-63. [2] Vance S, Brown JM. Geochimica Cosmochimica Acta. 2013; 110:176-89. [3] Frank M, Runge C, Scott H, Maglio S, Olson J, Prakapenka V, et al. Physics of the Earth and Planetary Interiors. 2006; 155 :152-62. [4] Frank MR, Aarestad E, Scott HP, Prakapenka VB. Physics of the Earth and Planetary Interiors. 2013; 215:12-20. [5] Klotz S, Bove L, Strässle T, Hansen T, Saitta A. Nat Mater. 2009; 8:405-9. [6] Mezouar, M. et al. Journal of Synchrotron Radiation. 2005; 12, 659-664.

  13. Planet Formation and the Characteristics of Extrasolar Planets

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    An overview of current theories of planetary growth, emphasizing the formation of extrasolar planets, is presented. Models of planet formation are based upon observations of the Solar System, extrasolar planets, and young stars and their environments. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth like terrestrial planets, but if they become massive enough before the protoplanetary disk dissipates, then they are able to accumulate substantial amounts of gas. These models predict that rocky planets should form in orbit about most single stars. It is uncertain whether or not gas giant planet formation is common, because most protoplanetary disks may dissipate before solid planetary cores can grow large enough to gravitationally trap substantial quantities of gas. A potential hazard to planetary systems is radial decay of planetary orbits resulting from interactions with material within the disk. Planets more massive than Earth have the potential to decay the fastest, and may be able to sweep up smaller planets in their path. The implications of the giant planets found in recent radial velocity searches for the abundances of habitable planets are discussed.

  14. Interiors of the Planets

    NASA Astrophysics Data System (ADS)

    Cook, A. H.

    2009-06-01

    1. Introduction; 2. The internal structure of the Earth; 3. Methods for the determination of the dynamical properties of planets; 4. Equations of state of terrestrial materials; 5. The Moon; 6. Mars, Venus and Mercury; 7. High pressure metals; 8. Jupiter and Saturn, Uranus and Neptune; 9. Departures from the hydrostatic state; 10. Conclusion.

  15. Playing with Planets.

    ERIC Educational Resources Information Center

    Mann-Lewis, Melanie

    1989-01-01

    Presented are lessons which bridge the gap between concrete and abstract ideas by introducing students to the valuable idea of scale as it relates to space science. Included are information and activities on relative size, position, and orbital patterns of planets using mathematics to construct models. (RT)

  16. The Planet Formation Imager

    NASA Astrophysics Data System (ADS)

    Kraus, S.; Buscher, D. F.; Monnier, J. D.; PFI Science, the; Technical Working Group

    2014-04-01

    Among the most fascinating and hotly-debated areas in contemporary astrophysics are the means by which planetary systems are assembled from the large rotating disks of gas and dust which attend a stellar birth. Although important work is being done both in theory and observation, a full understanding of the physics of planet formation can only be achieved by opening observational windows able to directly witness the process in action. The key requirement is then to probe planet-forming systems at the natural spatial scales over which material is being assembled. By definition, this is the so-called Hill Sphere which delineates the region of influence of a gravitating body within its surrounding environment. The Planet Formation Imager project has crystallized around this challenging goal: to deliver resolved images of Hill-Sphere-sized structures within candidate planet-hosting disks in the nearest star-forming regions. In this contribution we outline the primary science case of PFI and discuss how PFI could significantly advance our understanding of the architecture and potential habitability of planetary systems. We present radiation-hydrodynamics simulations from which we derive preliminary specifications that guide the design of the facility. Finally, we give an overview about the interferometric and non-interferometric technologies that we are investigating in order to meet the specifications.

  17. Accumulation of the planets

    NASA Technical Reports Server (NTRS)

    Wetherill, G. W.

    1987-01-01

    In modeling the accumulation of planetesimals into planets, it is appropriate to distinguish between two stages: an early stage, during which approximately 10 km diameter planetesimals accumulate locally to form bodies approximate 10 to the 25th g in mass; and a later stage in which the approximately 10 to the 25th g planetesimals accumulate into the final planets. In the terrestrial planet region, an initial planetesimal swarm corresponding to the critical mass of dust layer gravitational instabilities is considered. In order to better understand the accumulation history of Mercury-sized bodies, 19 Monte-Carlo simulations of terrestrial planet growth were calculated. A Monte Carlo technique was used to investigate the orbital evolution of asteroidal collision debris produced interior to 2.6 AU. It was found that there are two regions primarily responsible for production of Earth-crossing meteoritic material and Apollo objects. The same techniques were extended to include the origin of Earth-approaching asteroidal bodies. It is found that these same two resonant mechanisms predict a steady-state number of Apollo-Amor about 1/2 that estimated based on astronomical observations.

  18. Planets and Pucks.

    ERIC Educational Resources Information Center

    Brueningsen, Christopher; Krawiec, Wesley

    1993-01-01

    Presents a simple activity designed to allow students to experimentally verify Kepler's second law, sometimes called the law of equal areas. It states that areas swept out by a planet as it orbits the Sun are equal for equal time intervals. (PR)

  19. Accumulation of the Planets

    NASA Technical Reports Server (NTRS)

    Wetherill, George W.

    2002-01-01

    The purpose of this project is to increase understanding of planet forming processes that are likely to have occurred in the Solar System during its early evolution. This was accomplished by development of computer models that are compatible with the present state of the Solar System as well as with observational and theoretical data attained from astrophysical observations and theory.

  20. Making and Differentiating Planets

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.

    2015-07-01

    The rocky planets formed by progressive aggregation of dust to make planetesimals which joined to make large objects called planetary embryos that finally accumulated into planets, one of which we live on. This chaotic process is complicated further by chemical changes with distance from the Sun, including differences in oxidation conditions and water concentration. Once the inner planets began to form, metallic iron sank to form cores, reacting with the rocky portions in the process. David C. Rubie (University of Bayreuth, Germany) and colleagues in Germany, France, and the United States put all this planetary action into an impressively thorough computer model of planet formation and differentiation. They show that the observed compositions of the Earth can be matched by simulations that include the Grand Tack (Jupiter and Saturn migrate inwards towards the Sun and then back out), and chemical gradients in the Solar System, with more reducing conditions near the Sun, more oxidizing farther from the Sun, and oxidizing and hydrated conditions even farther from the Sun. The study identifies other important variables, such as the extent to which metallic iron chemically equilibrated with the silicate making up the Earth's mantle, the pressure at which it happened, and the likelihood that Earth accreted heterogeneously.

  1. Twist planet drive

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1996-01-01

    A planetary gear system includes a sun gear coupled to an annular ring gear through a plurality of twist-planet gears, a speeder gear, and a ground structure having an internal ring gear. Each planet gear includes a solid gear having a first half portion in the form of a spur gear which includes vertical gear teeth and a second half portion in the form of a spur gear which includes helical gear teeth that are offset from the vertical gear teeth and which contact helical gear teeth on the speeder gear and helical gear teeth on the outer ring gear. One half of the twist planet gears are preloaded downward, while the other half are preloaded upwards, each one alternating with the other so that each one twists in a motion opposite to its neighbor when rotated until each planet gear seats against the sun gear, the outer ring gear, the speeder gear, and the inner ring gear. The resulting configuration is an improved stiff anti-backlash gear system.

  2. The Artificial Planet

    NASA Astrophysics Data System (ADS)

    Glover, D. R.

    An interim milestone for interstellar space travel is proposed: the artificial planet. Interstellar travel will require breakthroughs in the areas of propulsion systems, energy systems, construction of large space structures, protection from space & radiation effects, space agriculture, closed environmental & life support systems, and many other areas. Many difficult problems can be attacked independently of the propulsion and energy challenges through a project to establish an artificial planet in our solar system. Goals of the project would include construction of a large space structure, development of space agriculture, demonstration of closed environmental & life support systems over long time periods, selection of gravity level for long-term spacecraft, demonstration of a self-sufficient colony, and optimization of space colony habitat. The artificial planet would use solar energy as a power source. The orbital location will be selected to minimize effects of the Earth, yet be close enough for construction, supply, and rescue operations. The artificial planet would start out as a construction station and evolve over time to address progressive goals culminating in a self-sufficient space colony.

  3. A Planet for Goldilocks

    NASA Astrophysics Data System (ADS)

    Batalha, N.

    2014-07-01

    The search for life beyond Earth has inspired Solar System exploration and SETI surveys. Today, the search for life also leads to exoplanet discovery and characterization. Launched in March 2009, NASA's Kepler Mission has discovered thousands of exoplanets with diverse properties. Though each new world is interesting in its own right, Kepler aims to understand the population as a whole. Its primary objective is to determine the frequency of exoplanets of different sizes and orbital periods. Of special interest are the Earth-size planets in the “Goldilocks” (or habitable) Zone where the flux of incoming starlight is conducive to the existence of surface liquid water. Once Kepler establishes the prevalence of such planets in the Solar neighborhood, future missions can be designed to find not just a planet in the Goldilocks Zone but a planet for Goldilocks—a truly habitable environment for life as we know it. Kepler discoveries and progress will be described as well as the resources available to bring Kepler science to the public and into the classroom. The possibility of finding evidence of life beyond Earth is working its way into the public consciousness and has the potential to inspire generations. Scientific literacy is a natural consequence of awakening the spirit of exploration and discovery that led Goldilocks into the forest and leads humans into space.

  4. Planetsimals to Planets - Revisiting Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    Walsh, Kevin J.; Levison, Harold F.

    2015-11-01

    Nearly all previous models of terrestrial planet formation focus on either a short span of time or a narrow sliver of the disk to understand a specific mode of growth. The final stages of growth, the giant impact stage, are typically picked up after the growth of Moon- to Mars-sized embryos have grown and are spread throughout the disk.Here, by way of simulations starting with 30 km planetesimals that span the entire inner region of the Solar System, from 0.7 to 3.0 au, we examine the growth throughout the entire disk. We find that the growth is strongly inside-out, with Mars-sized embryos formed inside of 1 au before any embryos are formed beyond 2 au. Furthermore we test various effects owing to the existence or timescale of dispersal of the gaseous solar nebula on the stages of growth and timing of instabilities.

  5. [Seguro popular: achievements and perspectives].

    PubMed

    Chertorivski-Woldenberg, Salomón

    2011-01-01

    Healthcare systems are organized following one of two basic models: social security systems, which link access to health services to labor status, and national health systems, which grant access to health as a citizen's right. Mexico adopted, since the institutionalization of social security and healthcare services in 1943, a mixed system. Social security institutions covered the salaried workers and public assistance was granted to the remaining of the population. At the beginning of the XXI century the Mexican health system entered a crisis as the conditions to expand health coverage through social security were not met and public assistance services were insufficient. In order to address these developments, the Healthcare Social Protection System was founded (2004) as a mechanism to effectively guarantee every person's right to health as established after the constitutional amendment of article fourth in 1983. Seguro Popular is the mechanism that through federal and states' contributions seeks to financially protect the population without access to social security's health services, and thus prevent impoverishment due to out of pocket and catastrophic health expenditures. PMID:22116179

  6. Classifying Planets: Nature vs. Nurture

    NASA Astrophysics Data System (ADS)

    Beichman, Charles A.

    2009-05-01

    The idea of a planet was so simple when we learned about the solar system in elementary school. Now students and professional s alike are faced with confusing array of definitions --- from "Brown Dwarfs” to "Super Jupiters", from "Super Earths” to "Terrestrial Planets", and from "Planets” to "Small, Sort-of Round Things That Aren't Really Planets". I will discuss how planets might be defined by how they formed, where they are found, or by the life they might support.

  7. Water on Planets

    NASA Astrophysics Data System (ADS)

    Bell, James F.

    2010-11-01

    Water is an abundant molecule in the Cosmos. It has exploitable and unique spectroscopic and physical properties and has been found to be ubiquitous in places that we would expect in the standard model of solar system formation and nebular condensation: beyond the snow line in outer solar system planets, moons, asteroids, and comets. However, water is also an important constituent of planetary bodies (dominating at least one of their surfaces) in the inner solar system, likely indicating significant mixing between inner and outer solar system reservoirs of water during planetary accretion and the early history of the solar system. Water has played a critical role in the differential evolution of the terrestrial planets Venus, Earth, and Mars, and the concept of the “habitable zone” where liquid water could be stable on an Earth-like planet provides a starting point for assessing the habitability of worlds in our solar system and beyond. Examples of potentially habitable environments outside this zone in our own solar system warn us that this concept should only be a guide, however-important exceptions will no doubt occur. Recent discoveries of past liquid water and abundant present subsurface ice on Mars, of water reservoirs in unexpected places like the poles of Mercury and the Moon and the subsurface of Enceladus, of water in circumstellar disks and in the atmospheres of extrasolar planets, and the expectation of the discovery of water on Earth-like worlds in the habitable zones around other stars make this an exciting time in the study of water on planets both in our own solar system, and beyond.

  8. The Role of Popularity Goal in Early Adolescents' Behaviors and Popularity Status

    ERIC Educational Resources Information Center

    Dawes, Molly; Xie, Hongling

    2014-01-01

    The effect of popularity goal on the use of 3 popularity-related behaviors and later popularity status was examined in a diverse sample of 314 6th-grade students (176 girls and 138 boys) in both fall (Time 1) and spring (Time 2) semesters. Popularity goal and the use of popularity-driven behaviors (e.g., "I change the way I dress in order to…

  9. The Role of Popularity Goal in Early Adolescents' Behaviors and Popularity Status

    ERIC Educational Resources Information Center

    Dawes, Molly; Xie, Hongling

    2014-01-01

    The effect of popularity goal on the use of 3 popularity-related behaviors and later popularity status was examined in a diverse sample of 314 6th-grade students (176 girls and 138 boys) in both fall (Time 1) and spring (Time 2) semesters. Popularity goal and the use of popularity-driven behaviors (e.g., "I change the way I dress in order to

  10. Polarimetry of gas planets

    NASA Astrophysics Data System (ADS)

    Joos, Franco

    The quest for new worlds was not only an adventure at the times of Columbus. Also nowadays mankind searches for new, undiscovered territories. But today they lie no longer only on our Earth, but also well outside the solar system. There, new planets are sought and found. One of the challenges of modern astrophysics is the direct detection of extra- solar planets. To reach this goal, the largest available telescopes and most sophisticated detection techniques are required. A promising method to "see" and analyse extra-solar planets is based on the fact, that light reflected by a planet can be polarised. For its detection, accurate polarisation measurements are needed. This is one of the methods ESO intends to make use of to find new planets outside the solar system. The Institute of Astronomy of ETH Zürich contributes ZIMPOL to this planet-finder project. ZIMPOL is a very sensitive imaging polarimeter. This thesis is situated within the ESO-planet-finder project. It deals with two problems that are crucial for a successful mission: (1) Instrumental polarisation can seriously hamper the performance of the instrument. It is therefore essential, to keep instrumental polarisation very low. (2) A knowledge of the polarisation properties of our targets would be very helpful. For this reason the polarisation properties of our solar system planets are investigated. Promising candidates for a detection with ZIMPOL are large planets with atmospheres similar to those of our giant gas planets Jupiter, Saturn, Uranus and Neptune. In the first part of the thesis the planet-finder project is presented and the role of ZIMPOL is explained. To obtain the instrumental polarisation, the polarimetric properties of mirrors and other optical components of our planet- finder instrument are analysed. The instrumental polarisation for the wavelength range of 600 to 1000 nm and for all zenith distances is calculated with Mueller matrices. Methods for reducing the instrumental polarisation are proposed and checked by the renewed application of the Mueller calculus. The correction of the instrumental polarisation is divided into two parts. First, a combination of a rotating half-wave plate and a plane mirror compensate the polarisation introduced by the Nasmyth mirror. Secondly, a rotatable and tiltable glass plate compensates the residual polarisation introduced by oblique reflections on mirrors after the Nasmyth mirror. Further, possible aging effects of the mirrors are considered and consequences for the polarisation are highlighted. An error budget for non perfect retardation of the half-wave plate is also regarded, and the effects for the polarisation are calculated. In the second part spectropolarimetric measurements of the four gas planets Jupiter, Saturn, Uranus and Neptune for the wavelength range from 530 to 930 nm are presented. Our measurements of Uranus and Neptune are the first of their kind. For Uranus and Neptune a second-order scattering effect, leading to limb polarisation, has been measured. This effect is expected in atmospheres of Rayleigh scattering type and allows conclusions on the properties of the scatterers and the stratification inside the atmosphere. The limb polarisation reaches a maximum of more than 3% on Uranus. Spectropolarimetric plots for selected regions on Uranus and polarimetric profiles parallel to the spectrographic slits are presented. An enhanced polarisation in the methane absorption bands is detected. For both planets the limb polarisation decreases with wavelength. For Jupiter and Saturn profiles parallel to the slits and polarimetric spectra for some selected regions such as the poles of Jupiter or the ring system of Saturn are presented. The poles of Jupiter exhibit a large polarisation (up to 10%) perpendicular to the limb. In the methane absorption bands at the Jovian poles the polarisation is enhanced compared to the adjacent higher albedo regions. The polarisation decreases from short wavelengths towards longer wavelengths. Disc resolved spectropolarimetry of Saturn has not yet been published in the literature. Therefore, the spectropolarimetric data of Saturn presented in this thesis are the first of their kind. The polarised profiles for Saturn show an enhanced limb polarisation at the South Pole perpendicular to the limb and a small negative polarisation for the ring system (parallel to the scattering plane). In addition, we observe, an enhanced polarisation at northern mid- latitudes. An appendix is added that contains numerous spectropolarimetric plots and all profiles of the four planets. The main body of the text only contains a small selection of these data.

  11. Planet formation around millisecond pulsars

    NASA Technical Reports Server (NTRS)

    Banit, Menashe; Ruderman, Malvin; Shaham, Jacob

    1993-01-01

    We present a model for the formation of planets in circular orbits around millisecond pulsars. We propose that the planets originate from a circumbinary excretion disk around a binary millisecond pulsar and show how physical conditions in such a disk lead to the eventual formation of planets.

  12. Extrasolar Planets in the Classroom

    ERIC Educational Resources Information Center

    George, Samuel J.

    2011-01-01

    The field of extrasolar planets is still, in comparison with other astrophysical topics, in its infancy. There have been about 300 or so extrasolar planets detected and their detection has been accomplished by various different techniques. Here we present a simple laboratory experiment to show how planets are detected using the transit technique.

  13. Extrasolar Planets in the Classroom

    ERIC Educational Resources Information Center

    George, Samuel J.

    2011-01-01

    The field of extrasolar planets is still, in comparison with other astrophysical topics, in its infancy. There have been about 300 or so extrasolar planets detected and their detection has been accomplished by various different techniques. Here we present a simple laboratory experiment to show how planets are detected using the transit technique.…

  14. THE STEPPENWOLF: A PROPOSAL FOR A HABITABLE PLANET IN INTERSTELLAR SPACE

    SciTech Connect

    Abbot, D. S.; Switzer, E. R. E-mail: switzer@kicp.uchicago.edu

    2011-07-10

    Rogue planets have been ejected from their planetary system. We investigate the possibility that a rogue planet could maintain a liquid ocean under layers of thermally insulating water ice and frozen gas as a result of geothermal heat flux. We find that a rogue planet of Earth-like composition and age could maintain a subglacial liquid ocean if it were {approx}3.5 times more massive than Earth, corresponding to {approx}8 km of ice. Suppression of the melting point by contaminants, a layer of frozen gas, or a larger complement of water could significantly reduce the planetary mass that is required to maintain a liquid ocean. Such a planet could be detected from reflected solar radiation, and its thermal emission could be characterized in the far-IR if it were to pass within O(1000) AU of Earth.

  15. The Steppenwolf: A Proposal for a Habitable Planet in Interstellar Space

    NASA Astrophysics Data System (ADS)

    Abbot, D. S.; Switzer, E. R.

    2011-07-01

    Rogue planets have been ejected from their planetary system. We investigate the possibility that a rogue planet could maintain a liquid ocean under layers of thermally insulating water ice and frozen gas as a result of geothermal heat flux. We find that a rogue planet of Earth-like composition and age could maintain a subglacial liquid ocean if it were ≈3.5 times more massive than Earth, corresponding to ≈8 km of ice. Suppression of the melting point by contaminants, a layer of frozen gas, or a larger complement of water could significantly reduce the planetary mass that is required to maintain a liquid ocean. Such a planet could be detected from reflected solar radiation, and its thermal emission could be characterized in the far-IR if it were to pass within \\cal {O}(1000) AU of Earth.

  16. ALMOST ALL OF KEPLER'S MULTIPLE-PLANET CANDIDATES ARE PLANETS

    SciTech Connect

    Lissauer, Jack J.; Rowe, Jason F.; Bryson, Stephen T.; Howell, Steve B.; Jenkins, Jon M.; Kinemuchi, Karen; Koch, David G.; Marcy, Geoffrey W.; Adams, Elisabeth; Fressin, Francois; Geary, John; Holman, Matthew J.; Ragozzine, Darin; Buchhave, Lars A.; Ciardi, David R.; Fabrycky, Daniel C.; Ford, Eric B.; Morehead, Robert C.; Gilliland, Ronald L.; and others

    2012-05-10

    We present a statistical analysis that demonstrates that the overwhelming majority of Kepler candidate multiple transiting systems (multis) indeed represent true, physically associated transiting planets. Binary stars provide the primary source of false positives among Kepler planet candidates, implying that false positives should be nearly randomly distributed among Kepler targets. In contrast, true transiting planets would appear clustered around a smaller number of Kepler targets if detectable planets tend to come in systems and/or if the orbital planes of planets encircling the same star are correlated. There are more than one hundred times as many Kepler planet candidates in multi-candidate systems as would be predicted from a random distribution of candidates, implying that the vast majority are true planets. Most of these multis are multiple-planet systems orbiting the Kepler target star, but there are likely cases where (1) the planetary system orbits a fainter star, and the planets are thus significantly larger than has been estimated, or (2) the planets orbit different stars within a binary/multiple star system. We use the low overall false-positive rate among Kepler multis, together with analysis of Kepler spacecraft and ground-based data, to validate the closely packed Kepler-33 planetary system, which orbits a star that has evolved somewhat off of the main sequence. Kepler-33 hosts five transiting planets, with periods ranging from 5.67 to 41 days.

  17. How Giant Planets Shape the Characteristics of Terrestrial Planets

    NASA Astrophysics Data System (ADS)

    Barclay, Thomas; Quintana, Elisa V.

    2016-01-01

    The giant planets in the Solar System likely played a defining role in shaping the properties of the Earth and other terrestrial planets during their formation. Observations from the Kepler spacecraft indicate that terrestrial planets are highly abundant. However, there are hints that giant planets a few AU from their stars are not ubiquitous. It therefore seems reasonable to assume that many terrestrial planets lack a Jupiter-like companion. We use a recently developed, state-of-the-art N-body model that allows for collisional fragmentation to perform hundreds of numerical simulations of the final stages of terrestrial planet formation around a Sun-like star -- with and without giant outer planets. We quantify the effects that outer giant planet companions have on collisions and the planet accretion process. We focus on Earth-analogs that form in each system and explore how giant planets influence the relative frequency of giant impacts occurring at late times and the delivery of volitiles. This work has important implications for determining the frequency of habitable planets.

  18. The Effect of Star-Planet Interactions on Planetary Climate

    NASA Astrophysics Data System (ADS)

    Shields, Aomawa; Meadows, Victoria; Bitz, Cecilia; Pierrehumbert, Raymond; Joshi, Manoj; Robinson, Tyler; Agol, Eric; Barnes, Rory; Charnay, Benjamin; Virtual Planetary Laboratory

    2015-01-01

    In this work I explored the effect on planetary climate and habitability of interactions between a host star, an orbiting planet and additional planets in a stellar system. I developed and tested models that include both radiative and gravitational effects, and simulated planets covered by ocean, land and water ice, with incident stellar radiation from stars of different spectral types. These simulations showed that ice-covered conditions occurred on an F-dwarf planet with a much smaller decrease in stellar flux than planets orbiting stars with less near-UV radiation, due to ice reflecting strongly in the visible and near-UV. The surface ice-albedo feedback effect is less important at the outer edge of the habitable zone, where ˜3-10 bars of CO2 could entirely mask the climatic effect of ice and snow, leaving the traditional outer limit of the habitable zone unaffected by the spectral dependence of water ice and snow albedo. The exit out of global ice cover was also sensitive to host star spectral energy distribution. A planet orbiting an M-dwarf star exhibited a smaller resistance to melting out of a frozen state, requiring a smaller stellar flux to initiate deglaciation than planets orbiting hotter, brighter stars. Given their greater climate stability, planets orbiting cooler, lower-mass stars may be the best candidates for long-term habitability and life beyond the Solar System. A specific case was explored—that of Kepler-62f, a potentially habitable planet in a five-planet system orbiting a K-dwarf star. Simulations using a 3-D Global Climate Model indicated that Kepler-62f would have areas of the planet with surface temperatures above the freezing point of water with 1 bar or more of CO2 in its atmosphere. In a low-CO2 case, increases in planetary obliquity and orbital eccentricity coupled with an orbital configuration that places the summer solstice at or near pericenter generated regions of the planet with above-freezing surface temperatures, which may cause surface melting of an ice sheet formed during an annual cycle. The methods presented here can be used to assess the possible climates of newly discovered potentially habitable planets in systems with a wide range of orbital architectures.

  19. Mean Motion Resonances from Planet-Planet Scattering

    NASA Astrophysics Data System (ADS)

    Raymond, Sean N.; Barnes, Rory; Armitage, Philip J.; Gorelick, Noel

    2008-11-01

    Planet-planet scattering is the leading mechanism to explain the large eccentricities of the observed exoplanet population. However, scattering has not been considered important to the production of pairs of planets in mean motion resonances (MMRs). We present results from a large number of numerical simulations of dynamical instabilities in three-planet systems. We show that MMRs arise naturally in about 5% of cases. The most common resonances we populate are the 2:1 and 3:1 MMRs, although a wide variety of MMRs can occur, including high-order MMRs (up to 11th order). MMRs are generated preferentially in systems with uneven mass distributions: the smallest planet is typically ejected after a series of close encounters, leaving the remaining, more massive planets in resonance. The distribution of resonant planets is consistent with the phase-space density of resonant orbits, meaning that planets are randomly thrown into MMRs rather than being slowly pulled into them. It may be possible to distinguish between MMRs created by scattering versus convergent migration in a gaseous disk by considering planetary mass ratios: resonant pairs of planets beyond ~1 AU with more massive outer planets are likely to have formed by scattering. In addition, scattering may be responsible for pairs of planets in high-order MMRs (3:1 and higher) that are not easily populated by migration. The frequency of MMRs from scattering is comparable to the expected survival rate of MMRs in turbulent disks. Thus, planet-planet scattering is likely to be a major contributor to the population of resonant planets.

  20. Popularizing dissent: A civil society perspective.

    PubMed

    Motion, Judy; Leitch, Shirley; Weaver, C Kay

    2015-05-01

    This article theorizes civil society groups' attempts to popularize opposition to genetic modification in New Zealand as deliberative interventions that seek to open up public participation in science-society governance. In this case, the popularization strategies were designed to intensify concerns about social justice and democratic incursions, mobilize dissent and offer meaningful mechanisms for navigating and participating in public protest. Such civic popularization efforts, we argue, are more likely to succeed when popularity and politicization strategies are judiciously integrated to escalate controversy, re-negotiate power relations and provoke agency and action. PMID:25394361

  1. Mission to Planet Earth

    NASA Technical Reports Server (NTRS)

    Mclucas, John L.

    1989-01-01

    The Mission to Planet Earth is a research program designed to obtain information on the earth and the global changes taking place in the environment, including the 'natural'changes due to internal processes within the earth environment, the effects of energy and particles arriving from the outer space, and the effects of man and other living organisms inhabiting the earth. This paper emphasizes the need for multinational commitment to the collection of data on various global phenomena and for the 'end-to-end' management of the data handling process, which must combine data from many sources and do it properly to reveal useful information. The role of NASA and other space agencies in organizing these efforts is discussed. Special attention is given to the role of SAFISY (the Space Agency Forum for the International Space Year) formed with participation of 24 nations to coordinate the activities of various space agencies on the Mission to Planet Earth project.

  2. The Gemini Planet Imager

    NASA Astrophysics Data System (ADS)

    Macintosh, Bruce; Gemini Planet Imager instrument Team; Planet Imager Exoplanet Survey, Gemini; Observatory, Gemini

    2014-01-01

    The Gemini Planet Imager (GPI) is a next-generation adaptive optics coronagraph designed for direct imaging and spectroscopy of warm self-luminous extrasolar planets and polarimetry of circumstellar disks. It is the first such facility-class instrument deployed on a 8-m telescope, designed to be an order of magnitude more sensitive than existing high-contrast imaging capabilities. GPI has completed laboratory integration and testing, shipped to Gemini South, and is scheduled for first light in November 2013. I will present an overview of the GPI design and measured performance, and any first light results, including a public release of fully reduced data for selected targets. in 2014, GPI will be available for science validation, and in the second half of 2014, a large-scale exoplanet survey campaign will begin.

  3. Validating Kepler Planet Candidates

    NASA Astrophysics Data System (ADS)

    Lissauer, Jack J.; Torres, G.; Marcy, G.; Brown, T.; Gilliland, R.; Gautier, T. N.; Isaacson, H.; Dupree, A.; Kepler Science Team

    2011-01-01

    The Kepler Science Team has identified more than 700 transit-like signatures in the first 43 days of data returned from the spacecraft (Borucki et al. 2010, arXiv1006.2799B). However, only 7 of these candidates have been confirmed as planets as of late September 2010. The number of true planets in this sample is clearly far larger than 7, but the sample is also 'contaminated' with false-positives, including many from eclipsing binary stars. Separating the wheat from the chaff requires a careful study of individual candidates using both Kepler photometry and spectroscopic and imaging data from the ground. Techniques that the Science Team is developing to address these issues, which include detailed analysis of the photometric data and follow-up observations with ground-based telescopes, will be presented. Kepler was selected as the 10th mission of the Discovery Program. Funding for this mission is provided by NASA, Science Mission Directorate.

  4. Tenth Planet Discovered

    NASA Technical Reports Server (NTRS)

    2005-01-01

    These time-lapse images of a newfound planet in our solar system, called 2003UB313, were taken on Oct. 21, 2003, using the Samuel Oschin Telescope at the Palomar Observatory near San Diego, Calif. The planet, circled in white, is seen moving across a field of stars. The three images were taken about 90 minutes apart.

    A joint effort between JPL and the California Institute of Technology, the Palomar Observatory near San Diego houses a collection of famous telescopes, including the Hale 200-inch and Samuel Oschin 48-inch telescopes. The Palomar Adaptive Optics System, built by JPL and Caltech, corrects for the atmospheric blur of astronomical targets caused by turbulence in Earth's atmosphere. This system's camera was built by Cornell University, Ithaca, N.Y.

  5. Possible Habitability of Ocean Worlds

    NASA Astrophysics Data System (ADS)

    Noack, Lena; Höning, Dennis; Bredehöft, Jan H.; Lammer, Helmut

    2014-05-01

    In the last decade, the number of detected exoplanets has increased to over thousand confirmed planets and more as yet unconfirmed planet candidates. The scientific community mainly concentrates on terrestrial planets (up to 10 Earth masses) in the habitable zone, which describes the distance from the host star where liquid water can exist at the surface (Kasting et al., 1993). Another target group of interest are ocean worlds, where a terrestrial-like body (i.e. with an iron core and a silicate mantle) is covered by a thick water-ice layer - similar to the icy moons of our solar system but with several Earth masses (e.g. Grasset et al., 2009). When an exoplanet is detected and confirmed as a planet, typically the radius and the mass of it are known, leading to the mean density of the planet that gives hints to possible interior structures. A planet with a large relative iron core and a thick ocean on top of the silicate mantle for example would have the same average planet density as a planet with a more Earth-like appearance (where the main contributor to the mass is the silicate mantle). In this study we investigate how the radius and mass of a planet depend on the amount of water, silicates and iron present (after Wagner et al., 2011) the occurence of high-pressure-ice in the water-ice layer (note: we only consider surface temperatures at which liquid water exists at the surface) if the ocean layer influences the initiation of plate tectonics We assume that ocean worlds with a liquid ocean layer (and without the occurence of high-pressure ice anywhere in the water layer) and plate tectonics (especially the occurence of subduction zones, hydrothermal vents and continental formation) may be called habitable (Class III/IV habitats after Lammer et al., 2009). References: Kasting, J.F., Whitmire, D.P., and Reynolds, R.T. (1993). Habitable Zones around Main Sequence Stars. Icarus 101, 108-128. Grasset, O., Schneider, J., and Sotin, C. (2009). A study of the accuracy of mass-radius relationships for silicate-rich and ice-rich planets up to 100 Earth masses. The Astrophysical Journal 693, 722-733. Wagner, F.W., Sohl, F., Hussmann, H., Grott, M., and Rauer, H. (2011). Interior structure models of solid exoplanets using material laws in the infinite pressure limit. Icarus 214, 366-376. Lammer, H., Bredehöft, J.H., Coustenis, A., Khodachenko, M.L., Kaltenegger, L., Grasset, O., Prieur, D., Raulin, F., Ehrenfreund, P., Yamauchi, M., Wahlund, J.-E., Grießmeier, J.-M., Stangl, G., Cockell, C.S., Kulikov, Yu.N., Grenfell, J.L., and Rauer, H. (2009). What makes a planet habitable? Astron Astrophys Rev 17, 181-249.

  6. Theories of Giant Planet Formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Young, Richard E. (Technical Monitor)

    1998-01-01

    An overview of current theories of planetary formation, with emphasis on giant planets, is presented. The most detailed models are based upon observations of our own Solar System and of young stars and their environments. While these models predict that rocky planets should form around most single stars, the frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth as do terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. Most models for extrasolar giant planets suggest that they formed as did Jupiter and Saturn (in nearly circular orbits, far enough from the star that ice could), and subsequently migrated to their current positions, although some models suggest in situ formation.

  7. Dynamical Detection of Circumbinary Planets

    NASA Astrophysics Data System (ADS)

    Clark Fabrycky, Daniel; Orosz, Jerome; Welsh, William

    2015-12-01

    The Kepler data revealed a population of transiting gas-giant planets orbiting around close binary stars, beginning with Kepler-16, a highlight of the Extreme Solar Systems II meeting. Due to the restrictive geometry requirements of transit detections, this population is highly observationally biased towards coplanarity. However, a third of those planets detectably perturb their host binary's eclipse times, such that they could have been recognized even without transits. Here we announce the detection of three non-transiting planets based on this dynamical technique. Apsidal precession due to the planet makes the primary and secondary eclipse periods differ, and in addition a short-term modulation of the binary's eclipse times reveals the planet's orbital period. Several planetary periods are observed for each system, buttressing the interpretation. Though the method is nearly equally sensitive to all orbital orientations, each planet orbits near its host binary's plane, suggesting this class of planets formed in the circumbinary nebula.

  8. Observed properties of extrasolar planets.

    PubMed

    Howard, Andrew W

    2013-05-01

    Observational surveys for extrasolar planets probe the diverse outcomes of planet formation and evolution. These surveys measure the frequency of planets with different masses, sizes, orbital characteristics, and host star properties. Small planets between the sizes of Earth and Neptune substantially outnumber Jupiter-sized planets. The survey measurements support the core accretion model, in which planets form by the accumulation of solids and then gas in protoplanetary disks. The diversity of exoplanetary characteristics demonstrates that most of the gross features of the solar system are one outcome in a continuum of possibilities. The most common class of planetary system detectable today consists of one or more planets approximately one to three times Earth's size orbiting within a fraction of the Earth-Sun distance. PMID:23641110

  9. Formation of Giant Planets

    NASA Technical Reports Server (NTRS)

    Lin, Douglas

    1999-01-01

    Under the support of NASA Origins grant, we studied the formation of gaps in protoplanetary disks due the tidal interaction between a fully grown protoplanet and protostellar disk. The result of this study is published in the Astrophysical Journal, (vol 514, 344-367, 1999) and in several conference proceedings. The main focus of this work is to analyze planet-disk interaction during the final stages of protoplanetary formation.

  10. Planet Forming Protostellar Disks

    NASA Technical Reports Server (NTRS)

    Lubow, Stephen

    1998-01-01

    The project achieved many of its objectives. The main area of investigation was the interaction of young binary stars with surrounding protostellar disks. A secondary objective was the interaction of young planets with their central stars and surrounding disks. The grant funds were used to support visits by coinvestigators and visitors: Pawel Artymowicz, James Pringle, and Gordon Ogilvie. Funds were also used to support travel to meetings by Lubow and to provide partial salary support.

  11. Pluto: Dwarf planet 134340

    NASA Astrophysics Data System (ADS)

    Ksanfomality, L. V.

    2016-01-01

    In recent decades, investigations of Pluto with up-to-date astronomical instruments yielded results that have been generally confirmed by the New Horizons mission. In 2006, in Prague, the General Assembly of the International Astronomical Union (IAU) reclassified Pluto as a member of the dwarf planet category according to the criteria defined by the IAU for the term "planet". At the same time, interest in studies of Pluto was increasing, while the space investigations of Pluto were delayed. In 2006, the New Horizons Pluto spacecraft started its journey to Pluto. On July 14, 2015, the spacecraft, being in fly-by mode, made its closest approach to Pluto. The heterogeneities and properties of the surface and rarified atmosphere were investigated thoroughly. Due to the extreme remoteness of the spacecraft and the energy limitations, it will take 18 months to transmit the whole data volume. Along with the preliminary results of the New Horizons Pluto mission, this paper reviews the basics on Pluto and its moons acquired from the ground-based observations and with the Hubble Space Telescope (HST). There are only a few meteorite craters on the surfaces of Pluto and Charon, which distinctly marks them apart from such satellites of the giant planets as Ganymede and Callisto. The explanation is that the surface of Pluto is young: its age is estimated at less than 100 Myr. Ice glaciers of apparently a nitrogen nature were found. Nitrogen is also the main component of the atmosphere of Pluto. The planet demonstrates the signs of strong geologic activity, though the energy sources of these processes are unknown.

  12. Terrestrial Planet Geophysics

    NASA Astrophysics Data System (ADS)

    Phillips, R. J.

    2008-12-01

    Terrestrial planet geophysics beyond our home sphere had its start arguably in the early 1960s, with Keith Runcorn contending that the second-degree shape of the Moon is due to convection and Mariner 2 flying past Venus and detecting no planetary magnetic field. Within a decade, in situ surface geophysical measurements were carried out on the Moon with the Apollo program, portions of the lunar magnetic and gravity fields were mapped, and Jack Lorell and his colleagues at JPL were producing spherical harmonic gravity field models for Mars using tracking data from Mariner 9, the first spacecraft to orbit another planet. Moreover, Mariner 10 discovered a planetary magnetic field at Mercury, and a young Sean Solomon was using geological evidence of surface contraction to constrain the thermal evolution of the innermost planet. In situ geophysical experiments (such as seismic networks) were essentially never carried out after Apollo, although they were sometimes planned just beyond the believability horizon in planetary mission queues. Over the last three decades, the discipline of terrestrial planet geophysics has matured, making the most out of orbital magnetic and gravity field data, altimetric measurements of surface topography, and the integration of geochemical information. Powerful constraints are provided by tectonic and volcanic information gleaned from surface images, and the engagement of geologists in geophysical exercises is actually quite useful. Accompanying these endeavors, modeling techniques, largely adopted from the Earth Science community, have become increasingly sophisticated and have been greatly enhanced by the dramatic increase in computing power over the last two decades. The future looks bright with exciting new data sets emerging from the MESSENGER mission to Mercury, the promise of the GRAIL gravity mission to the Moon, and the re-emergence of Venus as a worthy target for exploration. Who knows? With the unflagging optimism and persistence of a few diehards, we may eventually have a seismic and heat flow network on Mars.

  13. THE INTERIOR DYNAMICS OF WATER PLANETS

    SciTech Connect

    Fu, Roger; O'Connell, Richard J.; Sasselov, Dimitar D. E-mail: richard_oconnell@harvard.ed

    2010-01-10

    The ever-expanding catalog of detected super-Earths calls for theoretical studies of their properties in the case of a substantial water layer. This work considers such water planets with a range of masses and water mass fractions (2-5 M{sub Earth}, 0.02%-50% H{sub 2}O). First, we model the thermal and dynamical structure of the near-surface for icy and oceanic surfaces, finding separate regimes where the planet is expected to maintain a subsurface liquid ocean and where it is expected to exhibit ice tectonics. Newly discovered exoplanets may be placed into one of these regimes given estimates of surface temperature, heat flux, and gravity. Second, we construct a parameterized convection model for the underlying ice mantle of higher ice phases, finding that materials released from the silicate-iron core should traverse the ice mantle on the timescale of 0.1 to 100 megayears. We present the dependence of the overturn times of the ice mantle and the planetary radius on total mass and water mass fraction. Finally, we discuss the implications of these internal processes on atmospheric observables.

  14. Complex patterns in the distribution of planets show planet migration and planet and star properties

    NASA Astrophysics Data System (ADS)

    Taylor, Stuart F.

    2015-08-01

    We present dramatic patterns in the distribution of exoplanet periods and eccentricities that vary as functions of iron abundance of the host star, planet mass, stellar properties, and presence of a stellar companion. These patterns include surprising peaks and gaps. They raise the question of whether planets themselves contribute to increasing stellar metallicity by causing other planets or material to “pollute” the star.We also show that the falloff in planets at the shortest periods can be used to determine the rate of planets migrating into the star as a function of the strength of tidal dissipation in the star. A small rate of planets migrating into the star can produce the observed population of the shortest period planets without having to invoke extremely weak tidal dissipation. Tidal dissipation strengths stronger than the tidal quality factor Q being equal to 107 are possible if there is a moderate flow of giant planets into the star. It is likely that within a decade it will be possible to measure the time shift of transits of the shortest period orbits due to orbital period decreases caused by tidal migration.The distribution of the shortest period planets indicates that the strength of tidal dissipation in stars is a function of stellar mass, making it worthwhile to monitor the shortest period systems for time shifts across a range of stellar masses. This time shift is inversely proportional to the lifetime of a planet.It is essential to know the rate of planets migrating into stars in order to understand whether inflated planets are only briefly inflated during a faster migration into the star, or if planets maintain anomalously large radii for longer periods of time.The paucity of Neptune-mass planets at the shortest periods could be due either to a lower rate of inward migration or to evaporation. Knowing how evaporation contributes to this paucity could help determine the fractions of planets that are rock, liquid water, or gas.

  15. Extrasolar planet detection

    NASA Technical Reports Server (NTRS)

    Korechoff, R. P.; Diner, D. J.; Tubbs, E. F.; Gaiser, S. L.

    1994-01-01

    This paper discusses the concept of extrasolar planet detection using a large-aperture infared imaging telescope. Coronagraphic stellar apodization techniques are less efficient at infrared wavelengths compared to the visible, as a result of practical limitations on aperture dimensions, thus necessitating additional starlight suppression to make planet detection feasible in this spectral domain. We have been investigating the use of rotational shearing interferometry to provide up to three orders of magnitude of starlight suppression over broad spectral bandwidths. We present a theoretical analysis of the system performance requirements needed to make this a viable instrument for planet detection, including specifications on the interferometer design and telescope aperture characteristics. The concept of using rotational shearing interferometry as a wavefront error detector, thus providing a signal that can be used to adaptively correct the wavefront, will be discussed. We also present the status of laboratory studies of on-axis source suppression using a recently constructed rotational shearing interferometer that currently operates in the visible.

  16. The Gemini Planet Imager

    NASA Astrophysics Data System (ADS)

    Graham, James R.; Macintosh, Bruce; Perrin, Marshall D.; Ingraham, Patrick; Konopacky, Quinn M.; Marois, Christian; Poyneer, Lisa; Bauman, Brian; Barman, Travis; Burrows, Adam Seth; Cardwell, Andrew; Chilcote, Jeffrey K.; De Rosa, Robert John J.; Dillon, Daren; Doyon, Rene; Dunn, Jennifer; Erikson, Darren; Fitzgerald, Michael P.; Gavel, Donald; Goodsell, Stephen J.; Hartung, Markus; Hibon, Pascale; Kalas, Paul; Larkin, James E.; Maire, Jerome; Marchis, Franck; Marley, Mark S.; McBride, James; Millar-Blanchaer, Max; Morzinski, Kathleen M.; Nielsen, Eric L.; Norton, Andew; Oppenheimer, Rebecca; Palmer, David; Patience, Jenny; Pueyo, Laurent; Rantakyro, Fredrik; Sadakuni, Naru; Saddlemeyer, Leslie; Savransky, Dmitry; Serio, Andrew W.; Soummer, Remi; Sivaramakrishnan, Anand; Song, Inseok; Thomas, Sandrine; Wallace, J. Kent; Wang, Jason; Wiktorowicz, Sloane; Wolff, Schulyer; Gpi/Gpies Team

    2015-01-01

    The Gemini Planet Imager (GPI) is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph with low spectral resolution but high spatial resolution. Every aspect of GPI has been tuned for maximum sensitivity to faint planets near bright stars. GPI has undergone a year of commissioning, verification, and calibration work. We have achieved an estimated H-band contrast (5-sigma) of 106 at 0.75 arcseconds and 105 at 0.35 arcseconds in spectral mode, and suppression of unpolarized starlight by a factor of 800 in imaging polarimetry mode. Early science observations include study of the spectra of β Pic b and HR 8799, orbital investigations of β Pic b and PZ Tel, and observations of the debris disk systems associated with β Pic, AU Mic, and HR 4796A. An 890-hour exoplanet survey with GPI is scheduled to begin in late 2014. A status report for the campaign will be presented.

  17. The Effect of Giant Planets on Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    Barclay, Thomas; Quintana, Elisa

    2015-12-01

    The giant planets in the Solar System likely played a defining role in shaping the properties of the Earth and other terrestrial planets during their formation. Observations from the Kepler spacecraft indicate that terrestrial planets are highly abundant. However, there are hints that giant planets a few AU from their stars are relatively uncommon based on long baseline radial velocity searches. It therefore seems reasonable to assume that many terrestrial planets lack a Jupiter-like companion. We use a recently developed, state-of-the-art N-body model that allows for collisional fragmentation to perform hundreds of numerical simulations of the final stages of terrestrial planet formation around a Sun-like star -- with and without giant outer planets. We quantify the effects that outer giant planet companions have on collisions and the planet accretion process. We focus on Earth-analogs that form in each system and explore how giant planets influence the relative frequency of giant impacts occurring at late times.

  18. PREDICTING PLANETS IN KEPLER MULTI-PLANET SYSTEMS

    SciTech Connect

    Fang, Julia; Margot, Jean-Luc

    2012-05-20

    We investigate whether any multi-planet systems among Kepler candidates (2011 February release) can harbor additional terrestrial-mass planets or smaller bodies. We apply the packed planetary systems hypothesis that suggests all planetary systems are filled to capacity, and use a Hill stability criterion to identify eight two-planet systems with significant gaps between the innermost and outermost planets. For each of these systems, we perform long-term numerical integrations of 10{sup 7} years to investigate the stability of 4000-8000 test particles injected into the gaps. We map out stability regions in orbital parameter space, and therefore quantify the ranges of semimajor axes and eccentricities of stable particles. Strong mean-motion resonances can add additional regions of stability in otherwise unstable parameter space. We derive simple expressions for the extent of the stability regions, which is related to quantities such as the dynamical spacing {Delta}, the separation between two planets in units of their mutual Hill radii. Our results suggest that planets with separation {Delta} < 10 are unlikely to host extensive stability regions, and that about 95 out of a total of 115 two-planet systems in the Kepler sample may have sizeable stability regions. We predict that Kepler candidate systems including KOI 433, KOI 72/Kepler-10, KOI 555, KOI 1596, KOI 904, KOI 223, KOI 1590, and KOI 139 can harbor additional planets or low-mass bodies between the inner and outer detected planets. These predicted planets may be detected by future observations.

  19. Mass-Radius Relationships for Low-Mass Planets: From Iron Planets to Water Planets

    NASA Technical Reports Server (NTRS)

    Kuchner, Marc

    2007-01-01

    Transit observations, and radial velocity measurements, have begun to populate the mass radius diagram for extrasolar planets; fubture astrometric measurements and direct images promise more mass and radius information. Clearly, the bulk density of a planet indicates something about a planet s composition--but what? I will attempt to answer this question in general for low-mass planets (planets obey a kind of universal mass-radius relationship: an expansion whose first term is M approx. R(sup 3).

  20. The Rocky Planet Survey

    NASA Astrophysics Data System (ADS)

    Fischer, Debra

    In direct support of the NASA Origins program, we propose the Rocky Planet Survey, a high cadence exoplanet search of sixty late G and K dwarf stars using the CHIRON spectrometer, which we built and commissioned at CTIO. CHIRON operates in two high- resolution modes (R=90,000 and R=120,000) and has a demonstrated precision of better than 1 m s-1. We are contributing 200 nights of telescope time for the next three years, for the excellent phase coverage needed to carry out this work. We have developed simulation software to optimize scheduling of observations to suppress aliases and quickly extract dynamical signals. Our science objectives are to (1) provide a statistical assessment of planet occurrence as a function of decreasing mass in the range of parameter space 3 < Msini < 30 MEARTH for orbital periods up to 50 days, (2) to determine the fraction of low mass planets in multi-planet architectures, and (3) detect planets with Msini < 3 MEARTH in orbital periods shorter than ~20 days. In addition to the science objectives, we intend to push the frontiers of extreme precision Doppler measurements to keep the U.S. competitive with the next generation of European Doppler spectroscopy (ESPRESSO on the VLT). Our team has significant expertise in optical design, fiber coupling, raw extraction, barycentric velocity corrections, and Doppler analysis. The proposed work includes a new optimal extraction algorithm, with the optical designers and software engineers working together on the 2-D PSF description needed for a proper row-by-row extraction and calibration. We will also develop and test upgrades to the barycentric correction code and improvements in the Doppler code that take advantage of stability in the dispersion solution, afforded by a new vacuum-enclosed grating upgrade (scheduled for November 2011). We will test use of emission wavelength calibrations to extend the iodine (absorption) wavelength calibration that we currently use to prepare for eventual use of stabilized etalons or laser frequency combs. Radial velocity measurements play a fundamental role, both in the detection of exoplanets and in support of NASA missions. This program will train postdoctoral fellows, grad students and undergrads, while helping the astronomical community to develop of instrumentation and software that outperform our current programs.

  1. New Indivisible Planetary Science Paradigm: Consequence of Questioning Popular Paradigms

    NASA Astrophysics Data System (ADS)

    Marvin Herndon, J.

    2014-05-01

    Progress in science involves replacing less precise understanding with more precise understanding. In science and in science education one should always question popular ideas; ask "What's wrong with this picture?" Finding limitations, conflicts or circumstances that require special ad hoc consideration sometimes is the key to making important discoveries. For example, from thermodynamic considerations, I found that the 'standard model of solar system formation' leads to insufficiently massive planetary cores. That understanding led me to discover a new indivisible planetary science paradigm. Massive-core planets formed by condensing and raining-out from within giant gaseous protoplanets at high pressures and high temperatures, accumulating heterogeneously on the basis of volatility with liquid core-formation preceding mantle-formation; the interior states of oxidation resemble that of the Abee enstatite chondrite. Core-composition was established during condensation based upon the relative solubilities of elements, including uranium, in liquid iron in equilibrium with an atmosphere of solar composition at high pressures and high temperatures. Uranium settled to the central region and formed planetary nuclear fission reactors, producing heat and planetary magnetic fields. Earth's complete condensation included a ~300 Earth-mass gigantic gas/ice shell that compressed the rocky kernel to about 66% of Earth's present diameter. T-Tauri eruptions, associated with the thermonuclear ignition of the Sun, stripped the gases away from the Earth and the inner planets. The T-Tauri outbursts stripped a portion of Mercury's incompletely condensed protoplanet and transported it to the region between Mars and Jupiter where it fused with in-falling oxidized condensate from the outer regions of the Solar System, forming the parent matter of ordinary chondrite meteorites, the main-Belt asteroids, and veneer for the inner planets, especially Mars. With its massive gas/ice shell removed, pressure began to build in the compressed rocky kernel of Earth and eventually the rigid crust began to crack. The major energy source for planetary decompression and for heat emplacement at the base of the crust is the stored energy of protoplanetary compression. In response to decompression-driven volume increases, cracks form to increase surface area and fold-mountain ranges form to accommodate changes in curvature. One of the most profound mysteries of modern planetary science is this: As the terrestrial planets are more-or-less of common chondritic composition, how does one account for the marked differences in their surface dynamics? Differences among the inner planets are principally due to the degree of compression experienced. Planetocentric georeactor nuclear fission, responsible for magnetic field generation and concomitant heat production, is applicable to compressed and non-compressed planets and large moons. The internal composition of Mercury is calculated based upon an analogy with the deep-Earth mass ratio relationships. The origin and implication of Mercurian hydrogen geysers is described. Besides Earth, only Venus appears to have sustained protoplanetary compression; the degree of which might eventually be estimated from understanding Venetian surface geology. A basis is provided for understanding that Mars essentially lacks a 'geothermal gradient' which implies potentially greater subsurface water reservoir capacity than previously expected. Resources at NuclearPlanet.com .

  2. Popular Music in American History. Revised.

    ERIC Educational Resources Information Center

    Reid, William, Jr.

    This student book encourages an understanding of U.S. history through song, and of American song through history. The book is organized in two main parts, the first focuses on the nature of popular music. It examines "What is Popular Music?" and looks at pop themes, lyrics, melodies, rhythm, the composer, performer, and publisher. The second part…

  3. Using Popular Culture to Teach Quantitative Reasoning

    ERIC Educational Resources Information Center

    Hillyard, Cinnamon

    2007-01-01

    Popular culture provides many opportunities to develop quantitative reasoning. This article describes a junior-level, interdisciplinary, quantitative reasoning course that uses examples from movies, cartoons, television, magazine advertisements, and children's literature. Some benefits from and cautions to using popular culture to teach…

  4. Popular Adult Education: The Bolivian Experience.

    ERIC Educational Resources Information Center

    Luft, Murray

    A discussion paper on popular adult non-formal education in rural Bolivia, based on four months of 1982 fieldwork, focuses on the nature of popular education and its meaning in a contemporary Bolivian context, program methods and operational strategies employed, outcomes and impacts on peasant participants (many of them Indians), and problems and…

  5. Popular Magazines Discuss Online Information Retrieval.

    ERIC Educational Resources Information Center

    Diodato, Virgil

    1984-01-01

    Examines 55 articles from 25 popular magazines such as "Better Homes and Gardens,""Business Week,""Popular Mechanics," and "Working Woman" and discusses purpose of the articles, consumer oriented online services, libraries and information centers, databases, and publishers and intermediaries. A list of the articles is appended. (EJS)

  6. Design and Teach a Popular Music Class.

    ERIC Educational Resources Information Center

    Love, Randolph D.

    1991-01-01

    Offers ideas on how to develop a course on popular music. Notes the importance of obtaining prior administrative support. Identifies materials, techniques, books, films, and community resources. Suggests several classroom projects, incorporating popular music history and music activities. Lists books, periodicals, and videotaped materials for…

  7. Popular Music and the Instrumental Ensemble.

    ERIC Educational Resources Information Center

    Boespflug, George

    1999-01-01

    Discusses popular music, the role of the musical performer as a creator, and the styles of jazz and popular music. Describes the pop ensemble at the college level, focusing on improvisation, rehearsals, recording, and performance. Argues that pop ensembles be used in junior and senior high school. (CMK)

  8. Substance Use in Popular Movies and Music.

    ERIC Educational Resources Information Center

    Roberts, Donald F.; Henriksen, Lisa; Christenson, Peter G.

    This study examines the frequency and nature of substance use in the most popular movie rentals and songs of 1996 and 1997. The intent was to determine the accuracy of public perceptions about extensive substance use in media popular among youth. Because teenagers are major consumers of movies and music, there is concern about the potential for…

  9. Anthropology and Popular Culture: A Case Study.

    ERIC Educational Resources Information Center

    Estes, Jack

    The study of popular culture in the United States is an appropriate anthropological endeavor, as evidenced in a case study of the volcanic eruption of Mt. St. Helens in Oregon. By examining its popular arts, anthropologists gain understanding of the culture and its people. For example, an analysis of reactions to the Mt. St. Helens eruption…

  10. Teaching Personality Theories Using Popular Music

    ERIC Educational Resources Information Center

    Leck, Kira

    2006-01-01

    Previously, psychology instructors have used popular music to illustrate psychological concepts in the classroom. In this study, students enrolled in a personality theories class heard 13 popular songs that demonstrated various concepts. Students then selected and analyzed their own songs that contained elements of personality theories. Test…

  11. Optimal Planet Properties For Plate Tectonics Through Time And Space

    NASA Astrophysics Data System (ADS)

    Stamenkovic, Vlada; Seager, Sara

    2014-11-01

    Both the time and the location of planet formation shape a rocky planet’s mass, interior composition and structure, and hence also its tectonic mode. The tectonic mode of a planet can vary between two end-member solutions, plate tectonics and stagnant lid convection, and does significantly impact outgassing and biogeochemical cycles on any rocky planet. Therefore, estimating how the tectonic mode of a planet is affected by a planet’s age, mass, structure, and composition is a major step towards understanding habitability of exoplanets and geophysical false positives to biosignature gases. We connect geophysics to astronomy in order to understand how we could identify and where we could find planet candidates with optimal conditions for plate tectonics. To achieve this goal, we use thermal evolution models, account for the current wide range of uncertainties, and simulate various alien planets. Based on our best model estimates, we predict that the ideal targets for plate tectonics are oxygen-dominated (C/O<1) (solar system like) rocky planets of ~1 Earth mass with surface oceans, large metallic cores super-Mercury, rocky body densities of ~7000kgm-3), and with small mantle concentrations of iron 0%), water 0%), and radiogenic isotopes 10 times less than Earth). Super-Earths, undifferentiated planets, and especially hypothetical carbon planets, speculated to consist of SiC and C, are not optimal for the occurrence of plate tectonics. These results put Earth close to an ideal compositional and structural configuration for plate tectonics. Moreover, the results indicate that plate tectonics might have never existed on planets formed soon after the Big Bang—but instead is favored on planets formed from an evolved interstellar medium enriched in iron but depleted in silicon, oxygen, and especially in Th, K, and U relative to iron. This possibly sets a belated Galactic start for complex Earth-like surface life if plate tectonics significantly impacts the build up and regulation of gases relevant for life. This allows for the first time to discuss the tectonic mode of a rocky planet from a practical astrophysical perspective.

  12. Astrometric Planet Searches with SIM PlanetQuest

    NASA Technical Reports Server (NTRS)

    Beichman, Charles A.; Unwin, Stephen C.; Shao, Michael; Tanner, Angelle M.; Catanzarite, Joseph H.; March, Geoffrey W.

    2007-01-01

    SIM will search for planets with masses as small as the Earth's orbiting in the habitable zones' around more than 100 of the stars and could discover many dozen if Earth-like planets are common. With a planned 'Deep Survey' of 100-450 stars (depending on desired mass sensitivity) SIM will search for terrestrial planets around all of the candidate target stars for future direct detection missions such as Terrestrial Planet Finder and Darwin, SIM's 'Broad Survey' of 2010 stars will characterize single and multiple-planet systems around a wide variety of stellar types, including many now inaccessible with the radial velocity technique. In particular, SIM will search for planets around young stars providing insights into how planetary systems are born and evolve with time.

  13. Formation of Outer Planets: Overview

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack

    2003-01-01

    An overview of current theories of planetary formation, with emphasis on giant planets is presented. The most detailed models are based upon observation of our own Solar System and of young stars and their environments. Terrestrial planets are believe to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. According to the prevailing core instability model, giant planets begin their growth by the accumulation of small solid bodies, as do terrestrial planets. However, unlike terrestrial planets, the growing giant cores become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk disspates. The primary questions regarding the core instability model is whether planets with small cores can accrete gaseous enveloples within the lifetimes of gaseous protoplanetary disks. The main alternative giant planet formation model is the disk instability model, in which gaseous planets form directly via gravitational instabilities within protoplanetary disks. Formation of giant planets via gas instability has never been demonstrated for realistic disk conditions. Moreover, this model has difficulty explaining the supersolar abundances of heavy elements in Jupiter and Saturn, and it does not explain the orgin of planets like Uranus and Neptune.

  14. Taxonomy of the extrasolar planet.

    PubMed

    Plávalová, Eva

    2012-04-01

    When a star is described as a spectral class G2V, we know that the star is similar to our Sun. We know its approximate mass, temperature, age, and size. When working with an extrasolar planet database, it is very useful to have a taxonomy scale (classification) such as, for example, the Harvard classification for stars. The taxonomy has to be easily interpreted and present the most relevant information about extrasolar planets. I propose an extrasolar planet taxonomy scale with four parameters. The first parameter concerns the mass of an extrasolar planet in the form of units of the mass of other known planets, where M represents the mass of Mercury, E that of Earth, N Neptune, and J Jupiter. The second parameter is the planet's distance from its parent star (semimajor axis) described in a logarithm with base 10. The third parameter is the mean Dyson temperature of the extrasolar planet, for which I established four main temperature classes: F represents the Freezing class, W the Water class, G the Gaseous class, and R the Roasters class. I devised one additional class, however: P, the Pulsar class, which concerns extrasolar planets orbiting pulsar stars. The fourth parameter is eccentricity. If the attributes of the surface of the extrasolar planet are known, we are able to establish this additional parameter where t represents a terrestrial planet, g a gaseous planet, and i an ice planet. According to this taxonomy scale, for example, Earth is 1E0W0t, Neptune is 1N1.5F0i, and extrasolar planet 55 Cnc e is 9E-1.8R1. PMID:22506608

  15. Partial Atmospheric Loss and Partial Mantle Melting during the Giant Impact Stage of Planet Formation

    NASA Astrophysics Data System (ADS)

    Stewart, S. T.; Lock, S. J.; Mukhopadhyay, S.

    2014-12-01

    Mantle noble gas data record evidence for multiple partial mantle magma oceans and atmospheric loss episodes on the growing Earth. Based on a broad suite of giant impact simulations, we develop widely-applicable scaling laws for blowoff of the atmosphere and an ocean. In addition, we consider the early time energy budget to estimate the volume of mantle melted by a giant impact. For the specific impact energies typical of terrestrial planet formation, partial atmospheric blowoff is common when an ocean is present, but ocean loss is rare. Atmospheric blowoff without an ocean requires impact energies on the high end expected during planet formation. Impact-generated full mantle magma oceans are rare events and partial mantle magma oceans are expected. Both giant impacts and planetesimal bombardment contribute significantly to the evolution of volatiles on a growing planet. Because the giant impact stage is stochastic, different sequences of giant impacts lead to differences in the volatile content and interior thermal states of the final planet.

  16. Planet-Planet Scattering and Outer Planetesimal Disks

    NASA Astrophysics Data System (ADS)

    Ford, E. B.

    2004-05-01

    Dynamical instabilities in planetary systems with multiple giant planets can lead to planets undergoing close encounters and ultimately being ejected from the planetary system. Before a planet is ejected, it typically goes through an extended period of time during which the planet's apocenter is raised to large radial distances. During this stage, the planet passes through the outer regions of the planetary system. Since the timescales for planet formation increase with radial distance, only small solid bodies form in the outer regions of the planetary system. A highly eccentric giant planet with large apocenter distance can excite eccentricities and clear out regions of this outer disk. Additionally, a massive outer disk may affect the orbit of the planet. We will present results of direct numerical simulations of highly eccentric giant planets interacting with an outer planetesimal disk. E.B.F. acknowledges the support of the Miller Institute for Basic Research and the Kavli Institute for Theoretical Physics. This research was supported in part by the Miller Institute for Basic Research, the Kavli Institute for Theoretical Physics, and the National Science Foundation under Grant No. PHY99-07949.

  17. Watching How Planets Form

    NASA Astrophysics Data System (ADS)

    2006-09-01

    Anatomy of a Planet-Forming Disc around a Star More Massive than the Sun With the VISIR instrument on ESO's Very Large Telescope, astronomers have mapped the disc around a star more massive than the Sun. The very extended and flared disc most likely contains enough gas and dust to spawn planets. It appears as a precursor of debris discs such as the one around Vega-like stars and thus provides the rare opportunity to witness the conditions prevailing prior to or during planet formation. "Planets form in massive, gaseous and dusty proto-planetary discs that surround nascent stars. This process must be rather ubiquitous as more than 200 planets have now been found around stars other than the Sun," said Pierre-Olivier Lagage, from CEA Saclay (France) and leader of the team that carried out the observations. "However, very little is known about these discs, especially those around stars more massive than the Sun. Such stars are much more luminous and could have a large influence on their disc, possibly quickly destroying the inner part." The astronomers used the VISIR instrument [1] on ESO's Very Large Telescope to map in the infrared the disc surrounding the young star HD 97048. With an age of a few million years [2], HD 97048 belongs to the Chameleon I dark cloud, a stellar nursery 600 light-years away. The star is 40 times more luminous than our Sun and is 2.5 times as massive. The astronomers could only have achieved such a detailed view due to the high angular resolution offered by an 8-metre size telescope in the infrared, reaching a resolution of 0.33 arcsecond. They discovered a very large disc, at least 12 times more extended than the orbit of the farthest planet in the Solar System, Neptune. The observations suggest the disc to be flared. "This is the first time such a structure, predicted by some theoretical models, is imaged around a massive star," said Lagage. ESO PR Photo 36/06 ESO PR Photo 36/06 A Flared Proto-Planetary Disc Such a geometry can only be explained if the disc contains a large amount of gas, in this case, at least as much as 10 times the mass of Jupiter. It should also contain more than 50 Earth masses in dust. The dust mass derived here is more than thousand times larger than what is observed in debris discs and Kuiper belt-like structures found around older, 'Vega-like' stars, such as Beta Pictoris, Vega, Fomalhaut and HR 4796. The dust around these stars is thought to be produced by collisions of larger bodies. The dust mass observed around HD 97048 is similar to the mass invoked for the (undetected) parent bodies in the more evolved systems. HD 97048's disc is thus most likely a precursor of debris discs observed around older stars. "From the structure of the disc, we infer that planetary embryos may be present in the inner part of the disc," said Lagage. "We are planning follow-up observations at higher angular resolution with ESO's VLT interferometer in order to probe these regions." A video, made by the CEA, is also available. More Information The scientists report their discovery in the 28 September issue of Science Express, the rapid online publication service of the journal Science: "Anatomy of a flaring proto-planetary disc around a young intermediate-mass star", by P.-O. Lagage et al. The team is composed of Pierre-Olivier Lagage, Coralie Doucet, and Eric Pantin, (CEA Saclay, France), Sébastien Charnoz (Paris 7 Denis Diderot University), Emilie Habart (Institut d'Astrophysique Spatiale, Orsay, France), Gaspard Duchêne, François Ménard, and Christophe Pinte (Laboratoire d'Astrophysique de Grenoble, France), and Jan-Willem Pel (Groningen University, The Netherlands).

  18. Debris Disks and Hidden Planets

    NASA Technical Reports Server (NTRS)

    Kuchner, Marc

    2008-01-01

    When a planet orbits inside a debris disk like the disk around Vega or Beta Pictoris, the planet may be invisible, but the patterns it creates in the disk may give it away. Observing and decoding these patterns may be the only way we can detect exo-Neptunes orbiting more than 20 AU from their stars, and the only way we can spot planets in systems undergoing the late stages of planet formation. Fortunately, every few months, a new image of a debris disk appears with curious structures begging for explanation. I'll describe some new ideas in the theory of these planet-disk interactions and provide a buyers guide to the latest models (and the planets they predict).

  19. Atmospheres of Extrasolar Giant Planets

    NASA Technical Reports Server (NTRS)

    Marley, Mark

    2006-01-01

    The next decade will almost certainly see the direct imaging of extrasolar giant planets around nearby stars. Unlike purely radial velocity detections, direct imaging will open the door to characterizing the atmosphere and interiors of extrasola planets and ultimately provide clues on their formation and evolution through time. This process has already begun for the transiting planets, placing new constraints on their atmospheric structure, composition, and evolution. Indeed the key to understanding giant planet detectability, interpreting spectra, and constraining effective temperature and hence evolution-is the atmosphere. I will review the universe of extrasolar giant planet models, focusing on what we have already learned from modeling and what we will likely be able to learn from the first generation of direct detection data. In addition to these theoretical considerations, I will review the observations and interpretation of the - transiting hot Jupiters. These objects provide a test of our ability to model exotic atmospheres and challenge our current understanding of giant planet evolution.

  20. Survival of extrasolar giant planet moons in planet-planet scattering

    NASA Astrophysics Data System (ADS)

    CIAN HONG, YU; Lunine, Jonathan; Nicholson, Phillip; Raymond, Sean

    2015-12-01

    Planet-planet scattering is the best candidate mechanism for explaining the eccentricity distribution of exoplanets. Here we study the survival and dynamics of exomoons under strong perturbations during giant planet scattering. During close encounters, planets and moons exchange orbital angular momentum and energy. The most common outcomes are the destruction of moons by ejection from the system, collision with the planets and the star, and scattering of moons onto perturbed but still planet-bound orbits. A small percentage of interesting moons can remain bound to ejected (free-floating) planets or be captured by a different planet. Moons' survival rate is correlated with planet observables such as mass, semi-major axis, eccentricity and inclination, as well as the close encounter distance and the number of close encounters. In addition, moons' survival rate and dynamical outcomes are predetermined by the moons' initial semi-major axes. The survival rate drops quickly as moons' distances increase, but simulations predict a good chance of survival for the Galilean moons. Moons with different dynamical outcomes occupy different regions of orbital parameter space, which may enable the study of moons' past evolution. Potential effects of planet obliquity evolution caused by close encounters on the satellites’ stability and dynamics will be reported, as well as detailed and systematic studies of individual close encounter events.

  1. Families of minor planets

    NASA Technical Reports Server (NTRS)

    Gradie, J. C.; Chapman, C. R.; Williams, J. G.

    1979-01-01

    Physical studies of individual family members show that at least the Themis, Eos, Koronis, Nysa/Hertha, and Budrosa families of minor planets are the result of the breakup of discrete parent bodies. Only a few families have been studied in detail, and even in those few cases, the full force of observational techniques has not been applied. Crucial for the understanding of families and their parent bodies are detailed physical studies of family members; precise mineralogical interpretation of observational data to identify the geochemistry of the parent bodies; and studies of the collisional evolution of family members.

  2. Planet X - Fact or fiction?

    NASA Technical Reports Server (NTRS)

    Anderson, John

    1988-01-01

    The search for a possible tenth planet in our solar system is examined. The history of the discoveries of Uranus, Neptune, and Pluto are reviewed. Searches of the sky with telescopes and theoretical studies of the gravitational influences on the orbits of known objects in the solar system are discussed. Information obtained during the Pioneer 10 and 11 missions which could suggest the presence of an undiscovered planet and computer simulations of the possible orbit of a tenth planet are presented.

  3. Planet X - ract or fiction

    SciTech Connect

    Anderson, J.

    1988-08-01

    The search for a possible tenth planet in our solar system is examined. The history of the discoveries of Uranus, Neptune, and Pluto are reviewed. Searches of the sky with telescopes and theoretical studies of the gravitational influences on the orbits of known objects in the solar system are discussed. Information obtained during the Pioneer 10 and 11 missions which could suggest the presence of an undiscovered planet and computer simulations of the possible orbit of a tenth planet are presented.

  4. Formation of the giant planets

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    2006-01-01

    The observed properties of giant planets, models of their evolution and observations of protoplanetary disks provide constraints on the formation of gas giant planets. The four largest planets in our Solar System contain considerable quantities of hydrogen and helium, which could not have condensed into solid planetesimals within the protoplanetary disk. All three (transiting) extrasolar giant planets with well determined masses and radii also must contain substantial amounts of these light gases. Jupiter and Saturn are mostly hydrogen and helium, but have larger abundances of heavier elements than does the Sun. Neptune and Uranus are primarily composed of heavier elements. HD 149026 b, which is slightly more massive than is Saturn, appears to have comparable quantities of light gases and heavy elements. HD 209458 b and TrES-1 are primarily hydrogen and helium, but may contain supersolar abundances of heavy elements. Spacecraft flybys and observations of satellite orbits provide estimates of the gravitational moments of the giant planets in our Solar System, which in turn provide information on the internal distribution of matter within Jupiter, Saturn, Uranus and Neptune. Atmospheric thermal structure and heat flow measurements constrain the interior temperatures of planets. Internal processes may cause giant planets to become more compositionally differentiated or alternatively more homogeneous; high-pressure laboratory .experiments provide data useful for modeling these processes. The preponderance of evidence supports the core nucleated gas accretion model. According to this model, giant planets begin their growth by the accumulation of small solid bodies, as do terrestrial planets. However, unlike terrestrial planets, the growing giant planet cores become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. The primary questions regarding the core nucleated growth model is under what conditions planets with small cores/total heavy element abundances can accrete gaseous envelopes within the lifetimes of gaseous protoplanetary disks.

  5. Starting a Planet Protectors Club

    ERIC Educational Resources Information Center

    US Environmental Protection Agency, 2007

    2007-01-01

    If your mission is to teach children how to reduce, reuse, and recycle waste and create the next generation of Planet Protectors, perhaps leading a Planet Protectors Club is part of your future challenges. You don't have to be an expert in waste reduction and recycling to lead a a Planet Protectors Club. You don't even have to be a teacher. You do…

  6. Revitalizing Ernst Mach's Popular Scientific Lectures

    NASA Astrophysics Data System (ADS)

    Euler, Manfred

    2007-06-01

    Compared to Ernst Mach's influence on the conceptual development of physics, his efforts to popularize science and his reflections on science literacy are known to a much lesser degree. The approach and the impact of Mach's popular scientific lectures are discussed in view of today's problems of understanding science. The key issues of Mach's popular scientific lectures, reconsidered in the light of contemporary science, still hold a high potential in fascinating a general audience. Moreover, Mach's grand theme, the relation of the physical to the psychical, is suited to contribute to a dialogue between different knowledge cultures, e.g. science and humanities.

  7. Cases of good and bad popularizing

    NASA Astrophysics Data System (ADS)

    Pekkola, Marko

    2010-05-01

    Scientific articles in average are read by few people and the impact of individual paper in the society may remain small. A typical press release might not help much. Simultaneously popular science magazines are seeking for news, but by reading the same channels it is easy to end up printing yesterdaýs digital news in predictable format. Yet an author who knows how and what to popularize, may win thousands of readers and simultaneously help the popular science magazine to win the news competition.

  8. Planet X - The current status

    NASA Astrophysics Data System (ADS)

    Seidelmann, P. K.; Harrington, R. S.

    Theoretical models of solar-system dynamics which predict the existence of a 10th planet (planet X) are surveyed and compared with recent observations. The history of the discoveries of Neptune and Pluto on the basis of discrepancies in the orbit of Uranus is recalled in detail, and the persistence of such discrepancies in 9-planet computations is considered. Particular attention is given to ongoing efforts to compute the current position of planet X, and to ground-based and space-based (IRAS and Pioneer) searches. Diagrams and graphs are provided.

  9. Four-planet meteorology

    NASA Technical Reports Server (NTRS)

    1979-01-01

    All planets with atmospheres have common characteristics which are helpful in understanding weather and climate on earth. Of the terrestrial planets, Mars displays the most earth-like characteristics. The feedback mechanism of the Martian Great Dust Storms may control climate on a global scale and shows some parallels to the water cycle on the earth. Venus, on the other hand, has atmosphere motions and characteristics far different from those of earth but appears to be valuable for comparative meteorology and it seems to be a simple weather machine due to absence of axial tilt. A completely gaseous Jupiter also can help because its atmosphere, driven by internal heat, flows round-and-round, showing the same general patterns for years at a time. Results of studying extraterrestrial atmospheres are most important for understanding earth's multi-year weather cycles such as the droughts in the American West every 22 years or effects of the Little Ice Age (1450-1915) on agriculture in the North Hemisphere.

  10. Planets and Life

    NASA Astrophysics Data System (ADS)

    Sullivan, Woodruff T., III; Baross, John

    2001-12-01

    Astrobiology involves the study of the origin and history of life on Earth, planets and moons where life may have arisen, and the search for extraterrestrial life. It combines the sciences of biology, chemistry, palaeontology, geology, planetary physics and astronomy. This textbook brings together world experts in each of these disciplines to provide the most comprehensive coverage of the field currently available. Topics cover the origin and evolution of life on Earth, the geological, physical and chemical conditions in which life might arise and the detection of extraterrestrial life on other planets and moons. The book also covers the history of our ideas on extraterrestrial life and the origin of life, as well as the ethical, philosophical and educational issues raised by astrobiology. Written to be accessible to students from diverse backgrounds, this text will be welcomed by advanced undergraduates and graduates who are taking astrobiology courses.• Compiled by world experts in their disciplines to create a truly comprehensive book • Accessible to students from a wide range of backgrounds • A welcome addition to this rapidly-growing field

  11. The Planet Venus

    NASA Astrophysics Data System (ADS)

    Luhmann, Janet

    This book is not so much for the space scientist looking for background material for research as it is for one interested in the history of planetary exploration. The first half (˜100 pps) is devoted to studies of Venus before the space age, starting at several hundred years BC. It is obvious from the multitude of detailed descriptions of observers' accounts that considerable library research went into this section. While sometimes tedious, this chronology of Venus research is punctuated with amusing facts. While many may know about the Velikovsky theory of the cometary origin of the planet, few may know that Lowell drew pictures of Cytherian canals similar to the canals of Mars or that Frederick the Great of Prussia proposed to name the (once suspected) satellite of Venus D'Alembert, after the mathematician. An equally amusing appendix shows the ups and downs of the rotation period of this planet with the invisible surface. Much attention is focused on early telescope observations, the ashen light, and transits of Venus. At the end of this half, one appreciates that Venus has played a fairly important role in history in the areas of religion, science, and technology.

  12. EUCLID microlensing planet search

    NASA Astrophysics Data System (ADS)

    Beaulieu, J.-P.; Tisserand, P.; Batista, V.

    2013-09-01

    The discovery of extrasolar planets is arguably the most exciting development in astrophysics during the past 15 years, rivalled only by the detection of dark energy. Two projects unite the communities of exoplanet scientists and cosmologists: the proposed ESA M class mission EUCLID and the large space mission WFIRST, top ranked by the Astronomy 2010 Decadal Survey report. The later states that: "Space-based microlensing is the optimal approach to providing a true statistical census of planetary systems in the Galaxy, over a range of likely semi-major axes". They also add: "This census, combined with that made by the Kepler mission, will determine how common Earth-like planets are over a wide range of orbital parameters" We will present a status report of the results obtained by microlensing on exoplanets, the new objectives of the next generation of ground based wide field imager networks. We will finally present the fantastic prospect offered by space based microlensing at the horizon 2020-2025.

  13. Stars and Planets

    NASA Astrophysics Data System (ADS)

    Neta, Miguel

    2014-05-01

    'Estrelas e Planetas' (Stars and Planets) project was developed during the academic year 2009/2010 and was tested on three 3rd grade classes of one school in Quarteira, Portugal. The aim was to encourage the learning of science and the natural and physical phenomena through the construction and manipulation of materials that promote these themes - in this case astronomy. Throughout the project the students built a small book containing three themes of astronomy: differences between stars and planets, the solar system and the phases of the Moon. To each topic was devoted two sessions of about an hour each: the first to teach the theoretical aspects of the theme and the second session to assembly two pages of the book. All materials used (for theoretical sessions and for the construction of the book) and videos of the finished book are available for free use in www.miguelneta.pt/estrelaseplanetas. So far there is only a Portuguese version but soon will be published in English as well. This project won the Excellency Prize 2011 of Casa das Ciências, a portuguese site for teachers supported by the Calouste Gulbenkian Fundation (www.casadasciencias.org).

  14. New Martian paradigms. [concerning planet's nature and evolution

    NASA Technical Reports Server (NTRS)

    Mcewen, Alfred S.

    1991-01-01

    Several interrelated paradigms concerning the nature and the evolution of Mars are discussed. These include an impact origin of the northern lowland, Mars as a water-rich planet, former oceans in the northern lowlands, a warm wet climate on early Mars, and the possibility of ancient life on Mars. Locations on Mars suggested for the search of possible ancient life include the heavily cratered terrain dissected by valley networks, possible lacustrine deposits in Valles Marineris, the oxidizing layer below the surface, sites along the fringes of the hypothetical northern circumpolar ocean, and in evaporite deposits.

  15. WATER TRAPPING ON TIDALLY LOCKED TERRESTRIAL PLANETS REQUIRES SPECIAL CONDITIONS

    SciTech Connect

    Yang, Jun; Abbot, Dorian S.; Liu, Yonggang; Hu, Yongyun

    2014-12-01

    Surface liquid water is essential for standard planetary habitability. Calculations of atmospheric circulation on tidally locked planets around M stars suggest that this peculiar orbital configuration lends itself to the trapping of large amounts of water in kilometers-thick ice on the night side, potentially removing all liquid water from the day side where photosynthesis is possible. We study this problem using a global climate model including coupled atmosphere, ocean, land, and sea ice components as well as a continental ice sheet model driven by the climate model output. For a waterworld, we find that surface winds transport sea ice toward the day side and the ocean carries heat toward the night side. As a result, nightside sea ice remains O(10 m) thick and nightside water trapping is insignificant. If a planet has large continents on its night side, they can grow ice sheets O(1000 m) thick if the geothermal heat flux is similar to Earth's or smaller. Planets with a water complement similar to Earth's would therefore experience a large decrease in sea level when plate tectonics drives their continents onto the night side, but would not experience complete dayside dessiccation. Only planets with a geothermal heat flux lower than Earth's, much of their surface covered by continents, and a surface water reservoir O(10%) of Earth's would be susceptible to complete water trapping.

  16. Inside-out planet formation

    SciTech Connect

    Chatterjee, Sourav; Tan, Jonathan C. E-mail: jt@astro.ufl.edu

    2014-01-01

    The compact multi-transiting planet systems discovered by Kepler challenge planet formation theories. Formation in situ from disks with radial mass surface density, Σ, profiles similar to the minimum mass solar nebula but boosted in normalization by factors ≳ 10 has been suggested. We propose that a more natural way to create these planets in the inner disk is formation sequentially from the inside-out via creation of successive gravitationally unstable rings fed from a continuous stream of small (∼cm-m size) 'pebbles', drifting inward via gas drag. Pebbles collect at the pressure maximum associated with the transition from a magnetorotational instability (MRI)-inactive ('dead zone') region to an inner MRI-active zone. A pebble ring builds up until it either becomes gravitationally unstable to form an ∼1 M {sub ⊕} planet directly or induces gradual planet formation via core accretion. The planet may undergo Type I migration into the active region, allowing a new pebble ring and planet to form behind it. Alternatively, if migration is inefficient, the planet may continue to accrete from the disk until it becomes massive enough to isolate itself from the accretion flow. A variety of densities may result depending on the relative importance of residual gas accretion as the planet approaches its isolation mass. The process can repeat with a new pebble ring gathering at the new pressure maximum associated with the retreating dead-zone boundary. Our simple analytical model for this scenario of inside-out planet formation yields planetary masses, relative mass scalings with orbital radius, and minimum orbital separations consistent with those seen by Kepler. It provides an explanation of how massive planets can form with tightly packed and well-aligned system architectures, starting from typical protoplanetary disk properties.

  17. The deep ocean under climate change.

    PubMed

    Levin, Lisa A; Le Bris, Nadine

    2015-11-13

    The deep ocean absorbs vast amounts of heat and carbon dioxide, providing a critical buffer to climate change but exposing vulnerable ecosystems to combined stresses of warming, ocean acidification, deoxygenation, and altered food inputs. Resulting changes may threaten biodiversity and compromise key ocean services that maintain a healthy planet and human livelihoods. There exist large gaps in understanding of the physical and ecological feedbacks that will occur. Explicit recognition of deep-ocean climate mitigation and inclusion in adaptation planning by the United Nations Framework Convention on Climate Change (UNFCCC) could help to expand deep-ocean research and observation and to protect the integrity and functions of deep-ocean ecosystems. PMID:26564845

  18. HARNESSING OCEAN WAVE ENERGY TO GENERATE ELECTRICITY

    EPA Science Inventory

    A technical challenge to sustainability is finding an energy source that is abundant enough to meet global demands without producing greenhouse gases or radioactive waste. Energy from ocean surface waves can provide the people of this planet a clean, endless power source to me...

  19. Tides in Giant Planets

    NASA Astrophysics Data System (ADS)

    Stevenson, David J.

    2015-11-01

    The arrival of Juno at Jupiter in less than a year necessitates analysis of what we can learn from the gravitational signal due to tides raised on the planet by satellites (especially Io but also Europa). In the existing literature, there is extensive work on static tidal theory (the response of the planet to a tidal potential whose time dependence is ignored) and this is what is usually quoted when people refer to tidal Love numbers. If this were correct then there would be almost no new information content in the measurement of tidally induced gravity field, since the perturbation is of the same kind as the response to rotation (i.e., the measurement of J2, a well-known quantity). However, tides are dynamic (that is, k2 is frequency dependent) and so there is new information in the frequency dependent part. There is also (highly important) information in the imaginary part (more commonly expressed as tidal Q) but there is no prospect of direct detection of this by Juno since that quadrature signal is so small. The difference between what we expect to measure and what we can already calculate directly from J2 is easily shown to be of order the square of tidal frequency over the lowest order normal mode frequency, and thus of order 10%. However, the governing equations are not simple (not separable) because of the Coriolis force. An approximate solution has been obtained for the n =1 polytrope showing that the correction to k2 is even smaller, typically a few percent, because the tidal frequency is not very different from twice the rotation frequency. Moreover, it is not highly sensitive to structure in standard models. However, the deep interior of the planet may be stably stratified because of a compositional gradient and this modifies the tidal flow amplitude, changing the dynamic k2 but not the static k2. This raises the exciting possibility that we can use the determination of k2 to set bounds on the extent of static stability, if any. There is also the slight possibility that the tidal frequency is coincidentally close to some resonance, as would be required if (as some have suggested) the tidal Q is currently small (e.g., a few thousand or less). Predictions and detectability for Juno will be presented.

  20. Planets and Life

    NASA Astrophysics Data System (ADS)

    Sullivan, Woodruff T., III; Baross, John

    2007-09-01

    Foreword; Preface; Contributors; Prologue; Part I. History: 1. History of astrobiological ideas W. T. Sullivan and D. Carney; 2. From exobiology to astrobiology S. J. Dick; Part II. The Physical Stage: 3. Formation of Earth-like habitable planets D. E. Brownlee and M. Kress; 4. Planetary atmospheres and life D. Catling and J. F. Kasting; Part III. The Origin of Life on Earth: 5. Does 'life' have a definition? C.E. Cleland and C. F. Chyba; 6. Origin of life: crucial issues R. Shapiro; 7. Origin of proteins and nucleic acids A. Ricardo and S. A. Benner; 8. The roots of metabolism G.D. Cody and J. H. Scott; 9. Origin of cellular life D. W. Deamer; Part IV. Life on Earth: 10. Evolution: a defining feature of life J. A. Baross; 11. Evolution of metabolism and early microbial communities J. A. Leigh, D. A. Stahl and J. T. Staley; 12. The earliest records of life on Earth R. Buick; 13. The origin and diversification of eukaryotes M. L. Sogin, D. J. Patterson and A. McArthur; 14. Limits of carbon life on Earth and elsewhere J. A. Baross, J. Huber and M. Schrenk; 15. Life in ice J. W. Deming and H. Eicken; 16. The evolution and diversification of life S. Awramik and K. J. McNamara; 17. Mass extinctions P. D. Ward; Part V. Potentially Habitable Worlds: 18. Mars B. M. Jakosky, F. Westall and A. Brack; 19. Europa C. F. Chyba and C. B. Phillips; 20. Titan J. I. Lunine and B. Rizk; 21. Extrasolar planets P. Butler; Part VI. Searching for Extraterrestrial Life: 22. How to search for life on other worlds C. P. McKay; 23. Instruments and strategies for detecting extraterrestrial life P. G. Conrad; 24. Societial and ethical concerns M. S. Race; 25. Planetary protection J. D. Rummel; 26. Searching for extraterrestrial intelligence J. C. Tarter; 27. Alien biochemistries P. D. Ward and S. A. Benner; Part VII. Future of the Field: 28. Disciplinary and educational opportunities L. Wells, J. Armstrong and J. Huber; Epilogue C. F. Chyba; Appendixes: A. Units and usages; B. Planetary properties; C. The geological time scale S. Awramik and K. J. McNamara; D. Astrobiological destinations on planet Earth J. Harnmeijer; E. Micro*scope web tool D. J. Patterson and M. L. Sogin; Index.

  1. More than Just a Planet

    NASA Astrophysics Data System (ADS)

    Meal, It's. A.; Sandquist, Eric

    1999-01-01

    Can a star swallow a planet? the extrasolar planets discovered over the past two years display an odd range of characteristics - from their moasses to the size and shape of their orbits. Andy they just may offer us clues to stellar diets.

  2. Three Planets Orbiting Wolf 1061

    NASA Astrophysics Data System (ADS)

    Wright, D. J.; Wittenmyer, R. A.; Tinney, C. G.; Bentley, J. S.; Zhao, Jinglin

    2016-02-01

    We use archival HARPS spectra to detect three planets orbiting the M3 dwarf Wolf 1061 (GJ 628). We detect a 1.36 M⊕ minimum-mass planet with an orbital period P = 4.888 days (Wolf 1061b), a 4.25 M⊕ minimum-mass planet with orbital period P = 17.867 days (Wolf 1061c), and a likely 5.21 M⊕ minimum-mass planet with orbital period P = 67.274 days (Wolf 1061d). All of the planets are of sufficiently low mass that they may be rocky in nature. The 17.867 day planet falls within the habitable zone for Wolf 1061 and the 67.274 day planet falls just outside the outer boundary of the habitable zone. There are no signs of activity observed in the bisector spans, cross-correlation FWHMs, calcium H & K indices, NaD indices, or Hα indices near the planetary periods. We use custom methods to generate a cross-correlation template tailored to the star. The resulting velocities do not suffer the strong annual variation observed in the HARPS DRS velocities. This differential technique should deliver better exploitation of the archival HARPS data for the detection of planets at extremely low amplitudes.

  3. The Fate of Scattered Planets

    NASA Astrophysics Data System (ADS)

    Bromley, Benjamin C.; Kenyon, Scott J.

    2014-12-01

    As gas giant planets evolve, they may scatter other planets far from their original orbits to produce hot Jupiters or rogue planets that are not gravitationally bound to any star. Here, we consider planets cast out to large orbital distances on eccentric, bound orbits through a gaseous disk. With simple numerical models, we show that super-Earths can interact with the gas through dynamical friction to settle in the remote outer regions of a planetary system. Outcomes depend on planet mass, the initial scattered orbit, and the evolution of the time-dependent disk. Efficient orbital damping by dynamical friction requires planets at least as massive as the Earth. More massive, longer-lived disks damp eccentricities more efficiently than less massive, short-lived ones. Transition disks with an expanding inner cavity can circularize orbits at larger distances than disks that experience a global (homologous) decay in surface density. Thus, orbits of remote planets may reveal the evolutionary history of their primordial gas disks. A remote planet with an orbital distance ~100 AU from the Sun is plausible and might explain correlations in the orbital parameters of several distant trans-Neptunian objects.

  4. Giant Transiting Planets Observations GITPO

    NASA Astrophysics Data System (ADS)

    Afonso, C.; Henning, Th.; Weldrake, D.; Mazeh, T.; Dreizler, S.

    The search for extrasolar planets is nowadays one of the most promising science drivers in Astronomy. The radial velocity technique proved to be successful in planet hunting, harvesting more than a hundred planets to date. In these last recent years, the transit method has come to fruition, with the detection of seven Jupiter-mass extrasolar transiting planets in close-in orbits ({ AU). Currently, the radius of planets can only be determined from transiting planets, representing the principal motivation and strength of this technique. The MPIA is presently building the Large Area Imager (LAIWO) for the 1m telescope in the Wise Observatory, Israel. LAIWO will have a field of view of one square degree. An intensive search for extra-solar planets will be performed with the 1m Wise telescope, together with the 1.2m MONET telescope in Texas. We will monitor three fields at a given time during three years and more than 200 nights per year. We expect several dozens of extra-solar planets.

  5. Giant Transiting Planets Observations - GITPO

    NASA Astrophysics Data System (ADS)

    Afonso, C.

    2006-08-01

    The search for extrasolar planets is nowadays one of the most promising science drivers in Astronomy. The radial velocity technique proved to be successful in planet hunting, harvesting more than a hundred planets to date. In these last years, the transit method has come to fruition, with the detection of seven Jupiter-mass extrasolar transiting planets in close-in orbits (< 0.05 AU). Currently, the radius of planets can only be determined from transiting planets, representing the principal motivation and strength of this technique. The MPIA is presently building the Large Area Imager (LAIWO) for the 1m telescope in the Wise Observatory, Israel. LAIWO will have a field of view of one square degree. An intensive search for extra-solar planets will be performed with the 1m Wise telecope, together with the 1.2m MONET telescope in Texas. We will monitor three fields at a given time during three years and more than 200 nights per year. We expect several dozens of extra-solar planets.

  6. Pluto: The Farthest Planet (Usually).

    ERIC Educational Resources Information Center

    Universe in the Classroom, 1988

    1988-01-01

    Provides background information about the planet Pluto. Includes the history of Pluto and discusses some of the common misconceptions about the planets. Addresses some of the recent discoveries about Pluto and contains a resource list of books, articles, and a videotape. (TW)

  7. The fate of scattered planets

    SciTech Connect

    Bromley, Benjamin C.; Kenyon, Scott J. E-mail: skenyon@cfa.harvard.edu

    2014-12-01

    As gas giant planets evolve, they may scatter other planets far from their original orbits to produce hot Jupiters or rogue planets that are not gravitationally bound to any star. Here, we consider planets cast out to large orbital distances on eccentric, bound orbits through a gaseous disk. With simple numerical models, we show that super-Earths can interact with the gas through dynamical friction to settle in the remote outer regions of a planetary system. Outcomes depend on planet mass, the initial scattered orbit, and the evolution of the time-dependent disk. Efficient orbital damping by dynamical friction requires planets at least as massive as the Earth. More massive, longer-lived disks damp eccentricities more efficiently than less massive, short-lived ones. Transition disks with an expanding inner cavity can circularize orbits at larger distances than disks that experience a global (homologous) decay in surface density. Thus, orbits of remote planets may reveal the evolutionary history of their primordial gas disks. A remote planet with an orbital distance ∼100 AU from the Sun is plausible and might explain correlations in the orbital parameters of several distant trans-Neptunian objects.

  8. Searching for Planets Around Pulsars

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-09-01

    Did you know that the very first exoplanets ever confirmed were found around a pulsar? The precise timing measurements of pulsar PSR 1257+12 were what made the discovery of its planetary companions possible. Yet surprisingly, though weve discovered thousands of exoplanets since then, only one other planet has ever been confirmed around a pulsar. Now, a team of CSIRO Astronomy and Space Science researchers are trying to figure out why.Formation ChallengesThe lack of detected pulsar planets may simply reflect the fact that getting a pulsar-planet system is challenging! There are three main pathways:The planet formed before the host star became a pulsar which means it somehow survived its star going supernova (yikes!).The planet formed elsewhere and was captured by the pulsar.The planet formed out of the debris of the supernova explosion.The first two options, if even possible, are likely to be rare occurrences but the third option shows some promise. In this scenario, after the supernova explosion, a small fraction of the material falls back toward the stellar remnant and is recaptured, forming what is known as a supernova fallback disk. According to this model, planets could potentially form out of this disk.Disk ImplicationsLed by Matthew Kerr, the CSIRO astronomers set out to systematically look for these potential planets that might have formed in situ around pulsars. They searched a sample of 151 young, energetic pulsars, scouring seven years of pulse time-of-arrival data for periodic variation that could signal the presence of planetary companions. Their methods to mitigate pulsar timing noise and model realistic orbits allowed them to have good sensitivity to low-mass planets.The results? They found no conclusive evidence that any of these pulsars have planets.This outcome carries with it some significant implications. The pulsar sample spans 2 Myr in age, in which planets should have had enough time to form in debris disks. The fact that none were detected suggests that long-lived supernova fallback disks may actually be much rarer than thought, or they exist only in conditions that arent compatible with planet formation.So if thats the case, what about the planets found around PSR 1257+12? This pulsar may actually be somewhat unique, in that it was born with an unusually weak magnetic field. This birth defect might have allowed it to form a fallback disk and, subsequently, planets where the sample of energetic pulsars studied here could not.CitationM. Kerr et al.2015 ApJ 809 L11 doi:10.1088/2041-8205/809/1/L11

  9. The naked planet Earth : Most essential pre-requisite for the origin and evolution of life

    NASA Astrophysics Data System (ADS)

    Maruyama, S.; Ikoma, M.; Genda, H.; Hirose, K.; Yokoyama, T.; Santosh, M.

    2013-12-01

    Our blue planet Earth has long been regarded as a standard to host evolving life with full of nutrients since the birth of the planet. Here, we synthesize the processes that led to the birth of early life on Earth and its aftermath, finally leading to the evolution of metazoans, based on an evaluation of: (1) source of nutrients, (2) chemistry of primordial ocean, (3) initial mass of ocean, and (4) size of rocky planet. Among the life-building nutrients, phosphorus (P) and potassium (K) play a key role. Only three types of rocks can serve as adequate source of nutrients. (a) Continent-forming TTG (granite), enabling the evolution of life to metazoans. (b) Primordial continents carrying anorthosite with KREEP (Potassium, Rare Earth Elements, and Phosphorus) basalts, which is a key to bear life. (c) Carbonatite magma, enriched in radiogenic elements such as U and Th, that can cause mutation to speed up evolution, and promote the birth of new species in continental rift settings. Second important factor is ocean chemistry. The primordial ocean was extremely acidic (pH=1-2) and enriched in halogens (Cl, F and others), S and N and metallic elements (Cd, Cu, Zn, and others), inhibiting the birth of life. Plate tectonics cleaned up these elements which interfered with RNA. Blue ocean finally appeared in the Phanerozoic with pH=7 through extensive interaction with surface continental crust by weathering, erosion and transportation into ocean. The initial ocean mass was also important. The birth of life and aftermath of evolution was possible in the habitable zone under a tight initial condition of 3-5 km thick ocean which enabled supply of sufficient nutrients. Without a huge landmass, sufficient amount of nutrients cannot be supplied into ocean. Finally, the size of the planet determines the fate of a planet. Due to suitable planet size, the dawn of Phanerozoic witnessed the initiation of return-flow of seawater into mantle, leading to the emergence of huge landmass above sea-level, and the distribution of nutrients on a global scale. It is necessary to meet above 4 conditions to enable the Earth as a habitable planet with evolved life forms. The tight constraints that we evaluate for birth and evolution of life on Earth would provide important guidelines for hunting for life in the exo-solar planets.

  10. Circumbinary Planets: Observations and Dynamics

    NASA Astrophysics Data System (ADS)

    Welsh, William F.; Orosz, Jerome A.; Fabrycky, Daniel; Haghighipour, Nader

    2015-08-01

    Circumbinary planet systems are in inherently dynamical systems - the Keplerian approximation fails to capture the essence of the orbital motions. Fortunately, the deviations from Keplerian motion in these triple-body (or more) configurations allow extremely precise mass and radius estimates, among the most precise for any planet or low-mass star. At the current time there are 10 known transiting circumbinary planets, plus several more candidates. Although few in number, the sample is large enough that interesting trends are emerging regarding the planets' radii, orbits, host-binary star periods, and proximity to the habitable zone. In this talk I will discuss the set of the Kepler circumbinary planets and their trends, present the latest discoveries and candidate systems, and comment on the necessity and benefits of full photodynamical modeling.

  11. Nonlinear tides in giant planets

    NASA Astrophysics Data System (ADS)

    Barker, Adrian J.

    2015-12-01

    Tidal interactions between short-period planets and their host stars can play an important role in the evolution of planetary orbits and stellar and planetary spins. For example, the observational preponderance of circular orbits among the shortest-period planets, with orbital periods shorter than about ten days, relative to those with wider orbits, is thought to be explained by tidal dissipation inside these planets. I will review recent work and present new results on the nonlinear evolution of tidal flows in rotating planets, which aims to understand the mechanisms responsible for tidal dissipation from first principles. I will describe the results of global hydrodynamical simulations of the elliptical instability, as well as the tidal excitation of inertial waves in a planet with a core, focusing on the role of nonlinear fluid effects. The importance of these mechanisms in explaining observations will be discussed.

  12. Astrophysics: Growing planet brought to light

    NASA Astrophysics Data System (ADS)

    Zhu, Zhaohuan

    2015-11-01

    Thousands of extrasolar planets have been discovered, but none is a planet in its infancy. Observations have finally been made of a young planet growing in its birthplace -- opening the way to many more such discoveries. See Letter p.342

  13. Habitable Planets: Interior Dynamics and Long-Term Evolution

    NASA Astrophysics Data System (ADS)

    Tackley, Paul J.; Ammann, Michael M.; Brodholt, John P.; Dobson, David P.; Valencia, Diana

    2014-04-01

    Here, the state of our knowledge regarding the interior dynamics and evolution of habitable terrestrial planets including Earth and super-Earths is reviewed, and illustrated using state-of-the-art numerical models. Convection of the rocky mantle is the key process that drives the evolution of the interior: it causes plate tectonics, controls heat loss from the metallic core (which generates the magnetic field) and drives long-term volatile cycling between the atmosphere/ocean and interior. Geoscientists have been studying the dynamics and evolution of Earth's interior since the discovery of plate tectonics in the late 1960s and on many topics our understanding is very good, yet many first-order questions remain. It is commonly thought that plate tectonics is necessary for planetary habitability because of its role in long-term volatile cycles that regulate the surface environment. Plate tectonics is the surface manifestation of convection in the 2900-km deep rocky mantle, yet exactly how plate tectonics arises is still quite uncertain; other terrestrial planets like Venus and Mars instead have a stagnant lithosphere- essentially a single plate covering the entire planet. Nevertheless, simple scalings as well as more complex models indicate that plate tectonics should be easier on larger planets (super-Earths), other things being equal. The dynamics of terrestrial planets, both their surface tectonics and deep mantle dynamics, change over billions of years as a planet cools. Partial melting is a key process influencing solid planet evolution. Due to the very high pressure inside super-Earths' mantles the viscosity would normally be expected to be very high, as is also indicated by our density function theory (DFT) calculations. Feedback between internal heating, temperature and viscosity leads to a superadiabatic temperature profile and self-regulation of the mantle viscosity such that sluggish convection still occurs.

  14. Educational And Public Outreach Software On Planet Detection For The Macintosh (TM)

    NASA Technical Reports Server (NTRS)

    Koch, David; Brady, Victoria; Cannara, Rachel; Witteborn, Fred C. (Technical Monitor)

    1996-01-01

    The possibility of extra-solar planets has been a very popular topic with the general public for years. Considerable media coverage of recent detections has only heightened the interest in the topic. School children are particularly interested in learning about space. Astronomers have the knowledge and responsibility to present this information in both an understandable and interesting format. Since most classrooms and homes are now equipped with computers this media can be utilized to provide more than a traditional "flat" presentation. An interactive "stack" has been developed using Hyperstudio (TM). The major topics include: "1996 - The Break Through Year In Planet Detection"; "What Determines If A Planet Is Habitable?"; "How Can We Find Other Planets (Search Methods)"; "All About the Kepler Mission: How To Find Earth-Sized Planets"; and "A Mission Simulator". Using the simulator, the student records simulated observations and then analyzes and interprets the data within the program stacks to determine the orbit and planet size, the planet's temperature and surface gravity, and finally determines if the planet is habitable. Additional related sections are also included. Many of the figures are animated to assist in comprehension of the material. A set of a dozen lesson plans for the middle school has also been drafted.

  15. From Pixels to Planets

    NASA Technical Reports Server (NTRS)

    Brownston, Lee; Jenkins, Jon M.

    2015-01-01

    The Kepler Mission was launched in 2009 as NASAs first mission capable of finding Earth-size planets in the habitable zone of Sun-like stars. Its telescope consists of a 1.5-m primary mirror and a 0.95-m aperture. The 42 charge-coupled devices in its focal plane are read out every half hour, compressed, and then downlinked monthly. After four years, the second of four reaction wheels failed, ending the original mission. Back on earth, the Science Operations Center developed the Science Pipeline to analyze about 200,000 target stars in Keplers field of view, looking for evidence of periodic dimming suggesting that one or more planets had crossed the face of its host star. The Pipeline comprises several steps, from pixel-level calibration, through noise and artifact removal, to detection of transit-like signals and the construction of a suite of diagnostic tests to guard against false positives. The Kepler Science Pipeline consists of a pipeline infrastructure written in the Java programming language, which marshals data input to and output from MATLAB applications that are executed as external processes. The pipeline modules, which underwent continuous development and refinement even after data started arriving, employ several analytic techniques, many developed for the Kepler Project. Because of the large number of targets, the large amount of data per target and the complexity of the pipeline algorithms, the processing demands are daunting. Some pipeline modules require days to weeks to process all of their targets, even when run on NASA's 128-node Pleiades supercomputer. The software developers are still seeking ways to increase the throughput. To date, the Kepler project has discovered more than 4000 planetary candidates, of which more than 1000 have been independently confirmed or validated to be exoplanets. Funding for this mission is provided by NASAs Science Mission Directorate.

  16. The Metallicity of Giant Planets

    NASA Astrophysics Data System (ADS)

    Thorngren, Daniel P.; Fortney, Jonathan

    2015-12-01

    Unique clues about the formation processes of giant planets can be found in their bulk compositions. Transiting planets provide us with bulk density determinations that can then be compared to models of planetary structure and evolution, to deduce planet bulk metallicities. At a given mass, denser planets have a higher mass fraction of metals. However, the unknown hot Jupiter "radius inflation" mechanism leads to under-dense planets that severely biases this work. Here we look at cooler transiting gas giants (Teff < 1000 K), which do not exhibit the radius inflation effect seen in their warmer cousins. We identified 40 such planets between 20 M_Earth and 20 M_Jup from the literature and used evolution models to determine their bulk heavy-element ("metal") mass. Several important trends are apparent. We see that all planets have at least ~10 M_Earth of metals, and that the mass of metal correlates strongly with the total mass of the planet. The heavy-element mass goes as the square root of the total mass. Both findings are consistent with the core accretion model. We also examined the effect of the parent star metallicity [Fe/H], finding that planets around high-metallicity stars are more likely to have large amounts of metal, but the relation appears weaker than previous studies with smaller sample sizes had suggested. We also looked for connections between bulk composition and planetary orbital parameters and stellar parameters, but saw no pattern, which is also an important result. This work can be directly compared to current and future outputs from planet formation models, including population synthesis.

  17. Which Ringed Planet...!?

    NASA Astrophysics Data System (ADS)

    2002-12-01

    Don't worry - you are not the only one who thought this was a nice amateur photo of planet Saturn, Lord of the Rings in our Solar System! But then the relative brightness and positions of the moons may appear somewhat unfamiliar... and the ring system does look unusually bright when compared to the planetary disk...?? Well, it is not Saturn, but Uranus , the next giant planet further out, located at a distance of about 3,000 million km, or 20 times the distance between the Sun and the Earth. The photo shows Uranus surrounded by its rings and some of the moons, as they appear on a near-infrared image that was obtained in the K s -band (at wavelength 2.2 µm) with the ISAAC multi-mode instrument on the 8.2-m VLT ANTU telescope at the ESO Paranal Observatory (Chile) . The exposure was made on November 19, 2002 (03:00 hrs UT) during a planetary research programme. The observing conditions were excellent (seeing 0.5 arcsec) and the exposure lasted 5 min. The angular diameter of Uranus is about 3.5 arcsec. The observers at ISAAC were Emmanuel Lellouch and Thérése Encrenaz of the Observatoire de Paris (France) and Jean-Gabriel Cuby and Andreas Jaunsen (both ESO-Chile). The rings The rings of Uranus were discovered in 1977, from observations during a stellar occultation event by astronomer teams at the Kuiper Airborne Observatory (KAO) and the Perth Observatory (Australia). Just before and after the planet moved in front of the (occulted) star, the surrounding rings caused the starlight to dim for short intervals of time. Photos obtained from the Voyager-2 spacecraft in 1986 showed a multitude of very tenuous rings. These rings are almost undetectable from the Earth in visible light. However, on the present VLT near-infrared picture, the contrast between the rings and the planet is strongly enhanced. At the particular wavelength at which this observation was made, the infalling sunlight is almost completely absorbed by gaseous methane present in the planetary atmosphere and the disk of Uranus therefore appears unsually dark. At the same time, the icy material in the rings reflects the sunlight and appears comparatively bright. Uranus is unique among the planets of the solar system in having a tilted rotation axis that is close to the main solar system plane in which most planets move (the "Ecliptic"). At the time of the Voyager-2 encounter (1986), the southern pole was oriented toward the Earth. Now, sixteen years later (corresponding to about one-fifth of Uranus' 84-year period of revolution), we observe the Uranian ring system at an angle that is comparable to the one under which we see Saturn when its ring system is most "open". The moons ESO PR Photo 31b/02 ESO PR Photo 31b/02 [Preview - JPEG: 400 x 526 pix - 76k] [Full-Res - JPEG: 1460 x 1919 pix - 1.1M] Caption : PR Photo 31b/02 provides identifications of the Uranian moons present in PR Photo 31a/02 . The unidentified, round object to the left is a background star. The image scale in indicated by the bar. Seven of the moons of Uranus have been identified in PR Photo 31b/02 [1]. Of these, Titania and Oberon are the brightest (visual magnitude about 14). They were first seen in 1787 by the discoverer of Uranus, William Herschel (1738-1822), working at Bath in England. Ariel and Umbriel were found in 1851 by William Lassell (1799-1880) at Liverpool in the same country. Miranda was discovered in 1948 by Gerard Kuiper (1905-1973) at the 5-m Palomar telescope in California (USA). The much smaller and fainter Puck and Portia (visual magnitude about 21 and barely visible in the photo) were first found in 1985-86 by Stephen P. Synnott of the Jet Propulsion Laboratory (USA), during a study of Voyager-2 photos obtained soon before this NASA spacecraft flew by Uranus in January 1986. Other VLT images If you now want to see a fine VLT photo of Saturn, please look at PR Photo 04a/02 , obtained in late 2001. It was made with the NAOS-CONICA (NACO) Adaptive Optics facility and is therefore much less influenced by atmospheric turbulence and hence correspondingly sharper than the present ISAAC image of Uranus. More VLT images are available in the VLT Photo Gallery .

  18. PLANET TOPERS: Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS

    NASA Astrophysics Data System (ADS)

    Dehant, Veronique; Breuer, Doris; Claeys, Philippe; Debaille, Vinciane; De Keyser, Johan; Javaux, Emmanuelle; Goderis, Steven; Karatekin, Ozgur; Mattielli, Nadine; Noack, Lena; Spohn, Tilman; Carine Vandaele, Ann; Vanhaecke, Frank; Van Hoolst, Tim; Wilquet, Valerie

    2013-04-01

    The PLANET TOPERS (Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS) group is an Inter-university attraction pole (IAP) addressing the question of habitability in our Solar System. Habitability is commonly understood as "the potential of an environment (past or present) to support life of any kind" (Steele et al., 2005, http://mepag.jpl.nasa.gov/reports/archive.html). Based on the only known example of Earth, the concept refers to whether environmental conditions are available that could eventually support life, even if life does not currently exist (Javaux and Dehant, 2010, Astron. Astrophys. Rev., 18, 383-416, DOI: 10.1007/s00159-010-0030-4). Life includes properties such as consuming nutrients and producing waste, the ability to reproduce and grow, pass on genetic information, evolve, and adapt to the varying conditions on a planet (Sagan, 1970, Encyclopedia Britannica, 22, 964-981). Terrestrial life requires liquid water. The stability of liquid water at the surface of a planet defines a habitable zone (HZ) around a star. In the Solar System, it stretches between Venus and Mars, but excludes these two planets. If the greenhouse effect is taken into account, the habitable zone may have included early Mars while the case for Venus is still debated. Important geodynamic processes affect the habitability conditions of a planet. As envisaged by the group, this IAP develops and closely integrates the geophysical, geological, and biological aspects of habitability with a particular focus on Earth neighboring planets, Mars and Venus. It works in an interdisciplinary approach to understand habitability and in close collaboration with another group, the Helmholtz Alliance "Life and Planet Evolution", which has similar objectives. The dynamic processes, e.g. internal dynamo, magnetic field, atmosphere, plate tectonics, mantle convection, volcanism, thermo-tectonic evolution, meteorite impacts, and erosion, modify the planetary surface, the possibility to have liquid water, the thermal state, the energy budget and the availability of nutrients. Shortly after formation (Hadean 4.4-4.0 Ga (billion years)), evidence supports the presence of a liquid ocean and continental crust on Earth (Wilde et al., 2001, Nature, 409, 175-178), Earth may thus have been habitable very early on. The origin of life is not understood yet but the oldest putative traces of life occur in the early Archaean (~3.5 Ga). Studies of early Earth habitats documented in rock containing traces of fossil life provide information about environmental conditions suitable for life beyond Earth, as well as methodologies for their identification and analyses. The extreme values of environmental conditions in which life thrives today can also be used to characterize the "envelope" of the existence of life and the range of potential extraterrestrial habitats. The requirement of nutrients for biosynthesis, growth, and reproduction suggest that a tectonically active planet, with liquid water is required to replenish nutrients and sustain life (as currently known). These dynamic processes play a key role in the apparition and persistence of life. This contribution will focus on the highlights of the work of the IAP Planet TOPERS.

  19. The Effect of Giant Planets on Habitable Planet Formation

    NASA Astrophysics Data System (ADS)

    Quintana, Elisa V.; Barclay, Thomas

    2016-06-01

    The giant planets in the Solar System likely played a large role in shaping the properties of the Earth during its formation. To explore their effects, we numerically model the growth of Earth-like planets around Sun-like stars with and without Jupiter and Saturn analog companions. Employing state-of-the-art dynamical formation models that allow both accretion and collisional fragmentation, we perform hundreds of simulations and quantify the specific impact energies of all collisions that lead to the formation of an Earth-analog. Our model tracks the bulk compositions and water abundances in the cores and mantles of the growing protoplanets to constrain the types of giant planet configurations that allow the formation of habitable planets. We find significant differences in the collisional histories and bulk compositions of the final planets formed in the presence of different giant planet configurations. Exoplanet surveys like Kepler hint at a paucity of Jupiter analogs, thus these analyses have important implications for determining the frequency of habitable planets and also support target selection for future exoplanet characterization missions.

  20. The Role of Giant Planets in Terrestrial Planet Formation

    NASA Astrophysics Data System (ADS)

    Levison, H. F.; Duncan, M. J.; Agnor, C. B.

    2000-05-01

    The dynamical structure of the outer planetary system has played a critical role in determining the sizes, numbers, and habitability of the terrestrial planets. In 1996, Wetherill showed that the presence of Jupiter affects the masses of planets in the Habitable Zone of the Sun. In addition, in our solar system the giant planets control the dynamics of most of Earth's impactors, which consist of objects from the asteroid belt, the Kuiper belt, the scattered comet disk, and the Oort cloud. At early times, these impactors may have been responsible for supplying the Earth with a significant fraction of its water, organics, and atmospheric volatiles. At later times, they are responsible for causing at least some mass extinctions. Recent observations have demonstrated that giant planet configurations can show startling variations from system to system. (Although the searches for extra-solar planets have yet to reveal anything about what `typical systems' are like due to strong observational biases.) The question therefore naturally arises: What kind of outer planetary systems can support habitable terrestrial planets? The Exobiology Program is funding us to undertake the first comprehensive study of the coupling between outer solar system architectures and inner solar system habitability. The first stage of this program was to construct a wide range of outer planetary systems. The results of this work can be found at www.boulder.swri.edu/ hal/diversity.html. Here we present a preliminary report on simulations of the formation of terrestrial planets in two of these synthetic outer planetary systems. The first contains 5 planets; three of which lie between 3.7 and 11AU and have a combined mass of 2600 Earth-masses ( 8 Jupiter-masses). The second system contains 7 planets between 4 and 35AU; the largest of which is only 26 Earth-masses ( 1.5 Neptune masses).

  1. THE FIRST PLANETS: THE CRITICAL METALLICITY FOR PLANET FORMATION

    SciTech Connect

    Johnson, Jarrett L.; Li Hui

    2012-06-01

    A rapidly growing body of observational results suggests that planet formation takes place preferentially at high metallicity. In the core accretion model of planet formation this is expected because heavy elements are needed to form the dust grains which settle into the midplane of the protoplanetary disk and coagulate to form the planetesimals from which planetary cores are assembled. As well, there is observational evidence that the lifetimes of circumstellar disks are shorter at lower metallicities, likely due to greater susceptibility to photoevaporation. Here we estimate the minimum metallicity for planet formation, by comparing the timescale for dust grain growth and settling to that for disk photoevaporation. For a wide range of circumstellar disk models and dust grain properties, we find that the critical metallicity above which planets can form is a function of the distance r at which the planet orbits its host star. With the iron abundance relative to that of the Sun [Fe/H] as a proxy for the metallicity, we estimate a lower limit for the critical abundance for planet formation of [Fe/H]{sub crit} {approx_equal} -1.5 + log (r/1 AU), where an astronomical unit (AU) is the distance between the Earth and the Sun. This prediction is in agreement with the available observational data, and carries implications for the properties of the first planets and for the emergence of life in the early universe. In particular, it implies that the first Earth-like planets likely formed from circumstellar disks with metallicities Z {approx}> 0.1 Z{sub Sun }. If planets are found to orbit stars with metallicities below the critical metallicity, this may be a strong challenge to the core accretion model.

  2. The occurrence of Jovian planets and the habitability of planetary systems

    PubMed Central

    Lunine, Jonathan I.

    2001-01-01

    Planets of mass comparable to or larger than Jupiter's have been detected around over 50 stars, and for one such object a definitive test of its nature as a gas giant has been accomplished with data from an observed planetary transit. By virtue of their strong gravitational pull, giant planets define the dynamical and collisional environment within which terrestrial planets form. In our solar system, the position and timing of the formation of Jupiter determined the amount and source of the volatiles from which Earth's oceans and the source elements for life were derived. This paper reviews and brings together diverse observational and modeling results to infer the frequency and distribution of giant planets around solar-type stars and to assess implications for the habitability of terrestrial planets. PMID:11158551

  3. The occurrence of Jovian planets and the habitability of planetary systems.

    PubMed

    Lunine, J

    2001-01-30

    Planets of mass comparable to or larger than Jupiter's have been detected around over 50 stars, and for one such object a definitive test of its nature as a gas giant has been accomplished with data from an observed planetary transit. By virtue of their strong gravitational pull, giant planets define the dynamical and collisional environment within which terrestrial planets form. In our solar system, the position and timing of the formation of Jupiter determined the amount and source of the volatiles from which Earth's oceans and the source elements for life were derived. This paper reviews and brings together diverse observational and modeling results to infer the frequency and distribution of giant planets around solar-type stars and to assess implications for the habitability of terrestrial planets. PMID:11158551

  4. Astrobiology And Extrasolar Planets- A New Lecture Course At Potsdam University

    NASA Astrophysics Data System (ADS)

    Franck, S. A.; von Bloh, W.; Bounama, Ch.

    2006-08-01

    Astrobiology studies the origin, evolution, distribution, and future of life on Earth and in the Universe. This addresses a very wide range of questions that have been asked by mankind from the beginning. On the other hand, the discovery of the first extrasolar planet orbiting a Sun-like star by Mayor and Queloz in 1995 opened a new area for astrobiological research. Although most of the newly discovered extrasolar planets are giants with no underlying solid surfaces or oceans that could support a biosphere, the distribution of masses lets scientists suppose that there must be a multitude of planets with lower masses, including Earth-mass planets. The lecture course contains the following topics: Survey about Extrasolar Planets, Detection Methods, Simple Earth System Models, Dynamical Earth System Models, Habitable Zones, Dynamical Habitability, Rare Earth Hypothesis, Drake Formula, Panspermia, Origin of Life, Cambrian Explosion, Impacts and Climate, Long-Term Future Scenarios, Future Space Missions.

  5. The Nitrogen Constraint on the Habitability of Planets around Low Mass M-stars

    NASA Astrophysics Data System (ADS)

    Tian, Feng

    2011-09-01

    The traditional habitable zones around stars are defined based on the stability of liquid water over geological timescales. Being too far away from the stars, the planet would be incapable of maintaining a warm surface and thus no liquid water. Being too close to the star, the planet would experience a 'runaway' greenhouse phase, during which its oceans could be lost quickly, and end up similar to our sister planet, Venus. The definition of tranditional habitable zones does not consider the availability of other elements important for life. All life as we know it needs nitrogen. Our calculations of upper planetary atmospheres show that nitrogen could be lost rapidly from planetary atmospheres with CO2 concentrations lower than certain threshold. This suggests that life on planets around low mass M-stars may be self-limiting, and planets of low mass M-stars are less favorable places to search for life than G- or K-type stars.

  6. The Nitrogen Constraint on Habitability of Planets of Low Mass M-stars

    NASA Astrophysics Data System (ADS)

    Tian, F.

    2011-12-01

    The traditional habitable zones around stars are defined based on the stability of liquid water over geological timescales. Being too far away from the stars, the planet would be incapable of maintaining a warm surface and thus no liquid water. Being too close to the star, the planet would experience a 'runaway' greenhouse phase, during which its oceans could be lost quickly, and end up similar to our sister planet, Venus. The definition of tranditional habitable zones does not consider the availability of other elements important for life. All life as we know it needs nitrogen. Our calculations of upper planetary atmospheres show that nitrogen could be lost rapidly from planetary atmospheres with CO2 concentrations lower than certain threshold. This suggests that life on planets around low mass M-stars may be selflimiting, and planets of low mass M-stars are less favorable places to search for life than G- or K-type stars.

  7. The Nitrogen Constraint on Habitability of Planets around Low Mass M-stars

    NASA Astrophysics Data System (ADS)

    Tian, F.

    2011-10-01

    The traditional habitable zones around stars are defined based on the stability of liquid water over geological timescales. Being too far away from the stars, the planet would be incapable of maintaining a warm surface and thus no liquid water. Being too close to the star, the planet would experience a 'runaway' greenhouse phase, during which its oceans could be lost quickly, and end up similar to our sister planet, Venus. The definition of tranditional habitable zones does not consider the availability of other elements important for life. All life as we know it needs nitrogen. Our calculations of upper planetary atmospheres show that nitrogen could be lost rapidly from planetary atmospheres with CO2 concentrations lower than certain threshold. This suggests that life on planets around low mass M-stars may be selflimiting, and planets of low mass M-stars are less favorable places to search for life than G- or K-type stars.

  8. Elliptical instability in terrestrial planets and moons

    NASA Astrophysics Data System (ADS)

    Cebron, D.; Le Bars, M.; Moutou, C.; Le Gal, P.; Maubert, P.

    2011-10-01

    Any planet may be subject to three kinds of harmonic mechanical forcing, driven respectively by libration, precession and tides. These forcings can generate flows in internal fluid layers such as fluid cores and subsurface oceans, whose dynamics then significantly differ from solid body rotation. In particular, tides and librations are known to be capable of exciting the so-called elliptical instability, corresponding to the destabilization of two-dimensional flows with elliptical streamlines, leading to three-dimensional turbulence. The presence of such an elliptical instability driven by tides and librations is investigated in terrestrial bodies. Its consequences on energy dissipation, on magnetic field induction and on heat flux fluctuations at the planetary scale are considered.

  9. Thermal light curves of Earth-like planets: 1. Varying surface and rotation on planets in a terrestrial orbit

    NASA Astrophysics Data System (ADS)

    Gómez-Leal, I.; Codron, F.; Selsis, F.

    2016-05-01

    The integrated thermal emission of an exoplanet and its variations along the orbital motion can carry information about the climatic conditions and the rotation of the planet. In this study, we use the LMDZ 3D Global Climate Model (GCM) to simulate the climate of a synthetic Earth and three quasi-Earth configurations: a slowly rotating Earth, an ocean-covered Earth and its snowball counterpart. We also generate the time-dependent broadband thermal emission of the planet from these simulations. In a first step, we validate the model by comparing the synthetic Earth emission with the actual emission of our planet as constrained by observations. Then, we determine the main properties of the climate and emission of the three Earth-like planets and compare them to those of the Earth. We show that planets with an uneven distribution of continents exhibit a maximum of emission during the summer of the hemisphere with larger continental masses, and they may exhibit a maximum of emission at apastron. Large convective clouds might form over the continents of slow rotating planets, having an important effect over their climate and their emission. We also show that, in all the modeled cases, the equilibrium temperature, the Bond albedo and the rotation period can in theory be retrieved from the light curve by a distant observer. The values obtained at transiting geometries have a low deviation from the global values for cases with an axis tilt similar to that of the Earth, and we are able to distinguish between the four planets presented here by the data obtained from their light curves. However, this might not be the case under different conditions.

  10. The planet and the painted globe

    SciTech Connect

    Rockwell, R.C.

    1994-12-31

    Some years ago a clever cartoonist drew a puzzled astronaut looking down on an Earth painted like a library globe: blocks of pinks, greens, and blues set off the countries, bold lines clearly delineated boundaries, and countries were identified in large letters. Research on human dimensions of global environmental changes would be so much easier if that cartographer`s globe were real. Unfortunately, what the astronauts have actually seen is a planet from which human politics have seemingly disappeared. They see an Earth on which the human creations of countries and their boundaries are veiled by the natural features of the planet-the oceans, seas, rivers, forests, ice fields, plain, and mountains that were mostly here before anyone thought to draw a national boundary or paint a map. This globe without apparent political demarcations is the natural stage on which environmental changes play. It is not, however, the globe on which social science research is conducted. The human-centered globe of the social sciences has places, cities, and nation-states of which social scientists must take account. How to do so in a manner that permits linkages of social and natural science research is problematic. This article discusses the interactions between these two different types of research in looking at global climate change.

  11. Terrestrial planets in high-mass disks without gas giants

    NASA Astrophysics Data System (ADS)

    de Elía, G. C.; Guilera, O. M.; Brunini, A.

    2013-09-01

    Context. Observational and theoretical studies suggest that planetary systems consisting only of rocky planets are probably the most common in the Universe. Aims: We study the potential habitability of planets formed in high-mass disks without gas giants around solar-type stars. These systems are interesting because they are likely to harbor super-Earths or Neptune-mass planets on wide orbits, which one should be able to detect with the microlensing technique. Methods: First, a semi-analytical model was used to define the mass of the protoplanetary disks that produce Earth-like planets, super-Earths, or mini-Neptunes, but not gas giants. Using mean values for the parameters that describe a disk and its evolution, we infer that disks with masses lower than 0.15 M⊙ are unable to form gas giants. Then, that semi-analytical model was used to describe the evolution of embryos and planetesimals during the gaseous phase for a given disk. Thus, initial conditions were obtained to perform N-body simulations of planetary accretion. We studied disks of 0.1, 0.125, and 0.15 M⊙. Results: All our simulations form massive planets on wide orbits. For a 0.1 M⊙ disk, 2-3 super-Earths of 2.8 to 5.9 M⊕ are formed between 2 and 5 AU. For disks of 0.125 and 0.15 M⊙, our simulations produce a 10-17.1 M⊕ planet between 1.6 and 2.7 AU, and other super-Earths are formed in outer regions. Moreover, six planets survive in the habitable zone (HZ). These planets have masses from 1.9 to 4.7 M⊕ and significant water contents ranging from 560 to 7482 Earth oceans, where one Earth ocean represents the amount of water on Earth's surface, which equals 2.8 × 10-4M⊕. Of the six planets formed in the HZ, three are water worlds with 39%-44% water by mass. These planets start the simulations beyond the snow line, which explains their high water abundances. In general terms, the smaller the mass of the planets observed on wide orbits, the higher the possibility to find water worlds in the HZ. In fact, massive planets can act as a dynamical barrier that prevents the inward diffusion of water-rich embryos located beyond the snow line. Conclusions: Systems without gas giants that harbor super-Earths or Neptune-mass planets on wide orbits around solar-type stars are of astrobiological interest. These systems are likely to harbor super-Earths in the HZ with significant water contents, which missions such as Kepler and Darwin should be able to find.

  12. Then Why Do They Call Earth the Blue Planet?

    NASA Technical Reports Server (NTRS)

    2005-01-01

    While the most common photographs of Earth taken from space show the planet covered in blue water, NASA has managed to produce detailed color images, using satellite imagery, that show the remarkable variation of colors that actually make up the oceanic surface. An ocean s color is determined by the interaction of surface waters with sunlight, and surface waters can contain any number of different particles and dissolved substances, which could then change the color. Then Why Do They Call Earth the Blue Planet? The particles are mostly phytoplankton, the microscopic, single-celled ocean plants that are the primary food source for much marine life. Remote detection of phytoplankton provides information about the uptake and cycling of carbon by the ocean through photosynthesis, as well as the overall health of the water. Inorganic particles and substances dissolved in the water also affect its color, particularly in coastal regions. Satellite images can be used to calculate the concentrations of these materials in surface waters, as well as the levels of biological activity. The satellites allow a global view that is not available from ship or shore. NASA s orbiting satellites offer a unique vantage point for studying the oceans. By resolving the biological, chemical, and physical conditions in surface waters, they have allowed the oceanographic community to make huge leaps in its understanding of oceanographic processes on regional and global fronts. The study of ocean color, in particular, has been integral in helping researchers understand the natural and human-induced changes in the global environment and establishing the role of the oceans in the biochemical cycles of elements that influence the climate and the distribution of life on Earth.

  13. No Pseudosynchronous Rotation for Terrestrial Planets and Moons

    NASA Astrophysics Data System (ADS)

    Makarov, Valeri V.; Efroimsky, Michael

    2013-02-01

    We re-examine the popular belief that a telluric planet or a satellite on an eccentric orbit can, outside a spin-orbit resonance, be captured in a quasi-static tidal equilibrium called pseudosynchronous rotation. The existence of such configurations was deduced from oversimplified tidal models assuming either a constant tidal torque or a torque linear in the tidal frequency. A more accurate treatment requires that the torque be decomposed into the Darwin-Kaula series over the tidal modes, and that this decomposition be combined with a realistic choice of rheological properties of the mantle, which we choose to be a combination of the Andrade model at ordinary frequencies and the Maxwell model at low frequencies. This development demonstrates that there exist no stable equilibrium states for solid planets and moons, other than spin-orbit resonances.

  14. NO PSEUDOSYNCHRONOUS ROTATION FOR TERRESTRIAL PLANETS AND MOONS

    SciTech Connect

    Makarov, Valeri V.; Efroimsky, Michael E-mail: michael.efroimsky@usno.navy.mil

    2013-02-10

    We re-examine the popular belief that a telluric planet or a satellite on an eccentric orbit can, outside a spin-orbit resonance, be captured in a quasi-static tidal equilibrium called pseudosynchronous rotation. The existence of such configurations was deduced from oversimplified tidal models assuming either a constant tidal torque or a torque linear in the tidal frequency. A more accurate treatment requires that the torque be decomposed into the Darwin-Kaula series over the tidal modes, and that this decomposition be combined with a realistic choice of rheological properties of the mantle, which we choose to be a combination of the Andrade model at ordinary frequencies and the Maxwell model at low frequencies. This development demonstrates that there exist no stable equilibrium states for solid planets and moons, other than spin-orbit resonances.

  15. Space activities and global popular music culture

    NASA Astrophysics Data System (ADS)

    Wessels, Allison Rae; Collins, Patrick

    During the "space age" era, space activities appear increasingly as a theme in Western popular music, as they do in popular culture generally. In combination with the electronics and tele-communications revolution, "pop/rock" music has grown explosively during the space age to become an effectively global culture. From this base a number of trends are emerging in the pattern of influences that space activities have on pop music. The paper looks at the use of themes and imagery in pop music; the role of space technology in the modern "globalization" of pop music; and current and future links between space activities and pop music culture, including how public space programmes are affected by its influence on popular attitudes.

  16. Evolution of popularity in given names

    NASA Astrophysics Data System (ADS)

    Lee, Mi Jin; Jo, Woo Seong; Yi, Il Gu; Baek, Seung Ki; Kim, Beom Jun

    2016-02-01

    An individual's identity in a human society is specified by his or her name. Differently from family names, usually inherited from fathers, a given name for a child is often chosen at the parents' disposal. However, their decision cannot be made in a vacuum but affected by social conventions and trends. Furthermore, such social pressure changes in time, as new names gain popularity while some other names are gradually forgotten. In this paper, we investigate how popularity of given names has evolved over the last century by using datasets collected in Korea, the province of Quebec in Canada, and the United States. In each of these countries, the average popularity of given names exhibits typical patterns of rise and fall with a time scale of about one generation. We also observe that notable changes of diversity in given names signal major social changes.

  17. FLIPPER: Validation for Remote Ocean Imaging

    NASA Technical Reports Server (NTRS)

    2006-01-01

    one of the determining factors in the planet s ability to support life is the same factor that makes the Blue Planet blue: water. Therefore, NASA researchers have a focused interest in understanding Earth s oceans and their ability to continue sustaining life. A critical objective in this study is to understand the global processes that control the changes of carbon and associated living elements in the oceans. Since oceans are so large, one of the most widely used methods of this research is remote sensing, using satellites to observe changes in the ocean color that may be indicative of changes occurring at the surface. Major changes in carbon are due to photosynthesis conducted by phytoplankton, showing, among other things, which areas are sustaining life. Although valuable for large-scale pictures of an ocean, remote sensing really only provides a surface, and therefore incomplete, depiction of that ocean s sustainability. True and complete testing of the water requires local testing in conjunction with the satellite images in order to generate the necessary algorithm parameters to calculate ocean health. For this reason, NASA has spearheaded research to provide onsite validation for its satellite imagery surveys.

  18. Visions of our Planet's Atmosphere, Land and Oceans

    NASA Technical Reports Server (NTRS)

    Hasler, A. F.

    2002-01-01

    The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to South Africa, Cape Town and Johannesburg using NASA Terra/MODIS data, Landsat data and 1 m IKONOS 'Spy Satellite' data. Zoom in to any place South Africa using Earth Viewer 3D from Keyhole Inc. and Landsat data at 30 m resolution Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes & 'tornadoes'. See the latest visualizations of spectacular images from NASANOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained.

  19. Spectra of Irradiated Giant Planets

    NASA Astrophysics Data System (ADS)

    Burrows, Adam; Sudarsky, David

    2002-11-01

    As many as 101 extrasolar giant planets (EGPs) have been detected by radial-velocity techniques, but none has been detected directly by its own emission or by reflection of the light from its parent star. We review the current state-of-the-art in the theoretical modeling of the spectra of giant planets outside the solar system and the basic theory of EGP spectra and atmospheres. We are now entering a new era of planet discovery and measurement. This contribution is meant to communicate some of the excitement in the astronomical community as the hunt for these exotic and remarkable objects accelerates.

  20. In Brief: Dwarf planet named

    NASA Astrophysics Data System (ADS)

    Zielinski, Sarah

    2006-09-01

    The dwarf planet 2003 UB313, which had been nicknamed `Xena,' has been given the formal name of Eris, the International Astronomical Union announced on 13 September. Eris, which was discovered in January 2005, was named for the Greek goddess of discord. Its moon has been named Dysnomia, for the daughter of Eris, the demon goddess of lawlessness. Eris was assigned dwarf planet status in an IAU resolution approved in August (see Eos 87(35), 2006) along with Pluto and Ceres. Pluto's demotion prompted the Minor Planet Center, which operates under the auspices of the IAU, to assign Pluto an asteroid number, 134340, on 7 September.

  1. Books and the popularization of science

    USGS Publications Warehouse

    Buchanan, R.

    1991-01-01

    This article discusses best-selling science books, the characteristics of the audience for popular science books, and the role of books within science popularization and science education. Best-selling science books have been rare, but generally readable. Regional books, also important sources of scientific information, aim at much smaller, far more price-sensitive audiences. Many successful regional, nontechnical science books are readable, heavily illustrated, and in some cases, cross-disciplinary. To increase the attentive audience for scientific information, improvement in science education is necessary, and the most efficacious role for scientific institutions may be the production of materials that can be easily incorporated into school curricula. ?? 1991 Springer.

  2. Astronomy Popularization via Sci-fi Movies

    NASA Astrophysics Data System (ADS)

    Li, Qingkang

    2015-08-01

    It is astronomers’ duty to let more and more young people know a bit astronomy and be interested in astronomy and appreciate the beauty and great achievements in astronomy. One of the most effective methods to popularize astronomy to young people nowadays might be via enjoying some brilliant sci-fi movies related to astronomy with some guidance from astronomers. Firstly, we will introduce the basic information of our selective course “Appreciation of Sci-fi Movies in Astronomy” for the non-major astronomy students in our University, which is surely unique in China, then we will show its effect on astronomy popularization based on several rounds of teaching.

  3. PLANET TOPERS: Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS

    NASA Astrophysics Data System (ADS)

    Dehant, Véronique; Breuer, Doris; Claeys, Philippe; Debaille, Vinciane; de Keyser, Johan; Javaux, Emmanuelle; Goderis, Steven; Karatekin, Ozgur; Matielli, Nadine; Noack, Lena; Spohn, Tilman; Carine Vandaele, Ann; Vanhaecke, Frank; van Hoolst, Tim; Wilquet, Valérie; The PLANET Topers Team

    2015-04-01

    The PLANET TOPERS (Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS) group is an Inter-university attraction pole (IAP) addressing the question of habitability in our Solar System. Based on the only known example of Earth, the concept refers to whether environmental conditions are available that could eventually support life, even if life does not currently exist. Life is believed to require liquid water, but important geodynamic processes affect the habitability conditions of a planet. The PLANET TOPERS group develops and closely integrates the geophysical, geological, and biological aspects of habitability with a particular focus on Earth neighboring planets, Mars and Venus. Habitability is commonly understood as "the potential of an environment (past or present) to support life of any kind" (Steele et al., 2005). Based on the only known example of Earth, the concept refers to whether environmental conditions are available that could eventually support life, even if life does not currently exist (Javaux and Dehant, 2010). Life includes properties such as consuming nutrients and producing waste, the ability to reproduce and grow, pass on genetic information, evolve, and adapt to the varying conditions on a planet (Sagan, 1970). Terrestrial life requires liquid water. The common view, however, is that extraterrestrial life would probably be based on organic chemistry in a water solvent (Pace, 2001) although alternative biochemistries have been hypothesized. The stability of liquid water at the surface of a planet defines a habitable zone (HZ) around a star. In the Solar System, it stretches between Venus and Mars, but excludes these two planets. If the greenhouse effect is taken into account, the habitable zone may have included early Mars while the case for Venus is still debated. The dynamic processes, e.g. internal dynamo, magnetic field, atmosphere, plate tectonics, mantle convection, volcanism, thermo-tectonic evolution, meteorite impacts, and erosion, modify the planetary surface, the possibility to have liquid water, the thermal state, the energy budget and the availability of nutrients. Shortly after formation (Hadean 4.4-4.0 Ga), evidence supports the presence of a liquid ocean and continental crust on Earth (Wilde et al., 2001), Earth may thus have been habitable very early on (Strasdeit, 2010). The origin of life is not understood yet but the oldest putative traces of life occur in the early Archaean (~3.5 Ga). The extreme values of environmental conditions in which life thrives today can also be used to characterize the "envelope" of the existence of life and the range of potential extraterrestrial habitats. The requirement of nutrients for biosynthesis, growth, and reproduction suggests that a tectonically active planet, with liquid water is required to replenish nutrients and sustain life (as currently known). These dynamic processes play a key role in the apparition and persistence of life. Mars is presently on the edge of the HZ, but may have been much more hospitable early in its history, as the examination of its surface suggests the existence of water very early on (about 4 Ga ago) (Bibring et al., 2005; 2006). Since then, Mars lost most of its atmosphere, preventing the presence of liquid water at the surface. In comparison Earth is habitable at present and has been for at least 3.5 Ga.

  4. Irreversible evolution of the terrestrial planets (geological and petrological data)

    NASA Astrophysics Data System (ADS)

    Sharkov, E.; Bogatikov, O.

    2008-09-01

    Abstract Comparative studying of tectonomagmatic evolution of the Earth and the Moon shows that cardinal irreversible change in character of tectonomagmatic processes occurred at middle stages of their evolution; very likely such changes took place on other terrestrial planets (Venus, Mars and Mercury). As a result, primordial crusts of the planets were in considerable degree replaced by secondary basaltic ones. The established succession of events on the Earth could be provided by a combination of two independent factors: (1) it was originally heterogeneous and 2) its downward heating was followed by the cooling of its outer shells. As a result the primary iron core material was long time remained untouched and was involved into global tectonomagmatic processes at ca. 2.4-2.3 Ga. We concluded about a similar scenario for the evolution of Moon and other terrestrial planets. Tectonomagmatic evolution of the terrestrial planets (Earth, Venus, Mars, Mercury and Moon) was studied. What did major stages of their irreversible evolution occur before they turned into "dead" stone balls? We discuss these problems on examples of the Earth and the Moon, which evolution studied the best. According to modern views, after accretion of these bodies, magma oceans of some hundreds km deep appeared on their surface. According to Jeffries [1], solidification of large molted bodies, because of the difference between adiabatic gradient in silicate melts (0.3oC/km) and gradient of their melting points (3oC/km), could be going only upwards, from the bottom to the surface. As a result a powerful crystallizing differentiation of the oceans' magmas occurred with accumulation of the most low-melting components to the surface. Due to different deep of the magma oceans on the Earth and the Moon, the primordial crusts on these bodies were rather different: sialic on the Earth and basic (anorthosite) on the Moon.

  5. Comparative ionospheres. I - The inner planets. II - The outer planets

    NASA Technical Reports Server (NTRS)

    Cravens, T. E.

    1983-01-01

    A description is given first of the fundamental physical and chemical processes controlling the thermospheres and ionospheres of the inner planets, Venus and Mars. A comparison is made between the neutral composition and temperature structure of Venus and Mars and those of the earth. Consideration is then given to the chemical and diffusion processes in the ionosphere. After a brief treatment of the ionospheric energetics and heat sources, the mechanisms underlying the maintenance of the nightside ionosphere of Venus are reviewed. A description is then given of the upper atmospheres and ionospheres of the major planets, Jupiter and Saturn. The treatment of the temperature structure and composition of the thermospheres of the major planets includes a description of the physical and chemical processes controlling the hydrocarbons and atomic hydrogen. A comparison is then made between the ionospheres of the major planets and those of the inner planets. It is noted that Io and Titan also have atmospheres and ionospheres, and these are treated briefly. Even though comets cannot be classed as planets, they have atmospheres and ionospheres that are not gravitationally confined.

  6. NewsMars: Express journey to Mars ASE 2003: Knocked out by meteorites Events: Sun-Earth Day ASE 2003: Fun Physics - popular as ever Appointments: Sykes to bring science to the people UK Science Education: The future's bright, the future's science ASE 2003: A grand finale for Catherine Teaching Resources: UK goes to the planets Cambridge Physics Update: Basement physics Conferences: Earth Science Teachers' Association Conference 2003 New Website: JESEI sets sail GIREP: Teacher education seminar Malaysia: Rewards for curriculum change Cambridge Physics Update: My boomerang will come back! Teaching Resources: Widening particiption through ideas and evidence with the University of Surrey Wales: First Ffiseg Events: Nuna: Solar car on tour Physics on Stage: Physics on Stage 3 embraces life Symposium: In what sense a nuclear 'debate'? Gifted and Talented: Able pupils experiencing challenging science Australia: ISS flies high Down Under

    NASA Astrophysics Data System (ADS)

    2003-03-01

    Mars: Express journey to Mars ASE 2003: Knocked out by meteorites Events: Sun-Earth Day ASE 2003: Fun Physics - popular as ever Appointments: Sykes to bring science to the people UK Science Education: The future's bright, the future's science ASE 2003: A grand finale for Catherine Teaching Resources: UK goes to the planets Cambridge Physics Update: Basement physics Conferences: Earth Science Teachers' Association Conference 2003 New Website: JESEI sets sail GIREP: Teacher education seminar Malaysia: Rewards for curriculum change Cambridge Physics Update: My boomerang will come back! Teaching Resources: Widening particiption through ideas and evidence with the University of Surrey Wales: First Ffiseg Events: Nuna: Solar car on tour Physics on Stage: Physics on Stage 3 embraces life Symposium: In what sense a nuclear 'debate'? Gifted and Talented: Able pupils experiencing challenging science Australia: ISS flies high Down Under

  7. Abstracts of Popular Culture: A Quarterly Publication of International Popular Phenomena. Vol. 1:A.

    ERIC Educational Resources Information Center

    Browne, Ray B., Ed.

    Over 2100 articles concerned with popular culture, drawn from 188 American periodicals and a scattering of foreign publications, are scanned in this volume. Popular culture is defined as any aspect of life which is not academic or creative in the narrowest and most esoteric sense of the words. Thirty- to 150-word abstracts are provided of…

  8. Planets to Cosmology

    NASA Astrophysics Data System (ADS)

    Livio, Mario; Casertano, Stefano

    2011-11-01

    Preface; 1. Hubble's view of transiting planets D. Charbonneau; 2. Unsolved problems in star formation C. J. Clarke; 3. Star formation in clusters S. S. Larson; 4. HST abundance studies of low metallicity stars J. W. Truran, C. Sneden, F. Primas, J. J. Cowan and T. Beers; 5. Physical environments and feedback: HST studies of intense star-forming environments J. S. Gallagher, L. J. Smith and R. W. O'Connell; 6. Quasar hosts: growing up with monstrous middles K. K. McLeod; 7. Reverberation mapping of active galactic nuclei B. M. Peterson and K. Horne; 8. Feedback at high redshift A. E. Shapley; 9. The baryon content of the local intergalactic medium J. T. Stocke, J. M. Shull, and S. V. Penton; 10. Hot baryons in supercluster filaments E. D. Miller, R. A. Dupke and J. N. Bregman; 11. Galaxy assembly E. F. Bell; 12. Probing the reionization history of the Universe Z. Haiman; 13. Studying distant infrared-luminous galaxies with Spitzer and Hubble C. Papovich, E. Egami, E. Le Floc'h, P. Pérez-González, G. Rieke, J. Rigby, H. Dole and M. Reike; 14. Galaxies at z = g-i'-drop selection and the GLARE Project E. R. Stanway, K. Glazebrook, A. J. Bunker and the GLARE Consortium; 15. The Hubble Ultra Deep Field with NIMCOS R. I. Thompson, R. J. Bouwens and G. Illingworth.

  9. PLANETS ON THE EDGE

    SciTech Connect

    Valsecchi, Francesca; Rasio, Frederic A.

    2014-05-20

    Hot Jupiters formed through circularization of high-eccentricity orbits should be found at orbital separations a exceeding twice that of their Roche limit a {sub R}. Nevertheless, about a dozen giant planets have now been found well within this limit (a {sub R} < a < 2 a {sub R}), with one coming as close as 1.2 a {sub R}. In this Letter, we show that orbital decay (starting beyond 2 a {sub R}) driven by tidal dissipation in the star can naturally explain these objects. For a few systems (WASP-4 and 19), this explanation requires the linear reduction in convective tidal dissipation proposed originally by Zahn and verified by recent numerical simulations, but rules out the quadratic prescription proposed by Goldreich and Nicholson. Additionally, we find that WASP-19-like systems could potentially provide direct empirical constraints on tidal dissipation, as we could soon be able to measure their orbital decay through high precision transit timing measurements.

  10. Outer planets satellites

    NASA Technical Reports Server (NTRS)

    Morrison, D.

    1983-01-01

    The present investigation takes into account the published literature on outer planet satellites for 1979-1982. It is pointed out that all but three (the moon and the two Martian satellites) of the known planetary satellites are found in the outer solar system. Most of these are associated with the three regular satellite systems of Jupiter, Saturn, and Uranus. The largest satellites are Titan in the Saturn system and Ganymede and Callisto in the Jupiter system. Intermediate in size between Mercury and Mars, each has a diameter of about 5000 km. Presumably each has an internal composition about 60 percent rock and 40 ice, and each is differentiated with a dense core extending out about 75 percent of the distance to the surface, with a mantle of high-pressure ice and a crust of ordinary ice perhaps 100 km thick. Attention is also given to Io, Europa, the icy satellites of Saturn, the satellites of Uranus, the small satellites of Jupiter and Saturn, Triton and the Pluto system, and plans for future studies.

  11. Origin of the earth's ocean basins

    NASA Technical Reports Server (NTRS)

    Frex, H.

    1977-01-01

    The earth's original ocean basins were mare-type basins produced 4 billion years ago by the flux of asteroid-sized objects responsible for the lunar mare basins. Scaling upwards from the observed number of lunar basins for the greater capture cross-section and impact velocity of the Earth indicates that at least 50 percent of an original global crust would have been converted to basin topography. These basins were flooded by basaltic liquids in times short compared to the isostatic adjustment time for the basin. The modern crustal dichotomy (60 percent oceanic, 40 percent continental crust) was established early in the history of the earth, making possible the later onset of plate tectonic processes. These later processes have subsequently reworked, in several cycles, principally the oceanic parts of the earth's crust, changing the configuration of the continents in the process. Ocean basins (and oceans themselves) may be rare occurrences on planets in other star systems.

  12. Astrographic Positions of Minor Planets

    NASA Astrophysics Data System (ADS)

    Naskrecki, W.; Swierkowska, S.

    The paper presents the photographic position of minor planets taken in the years 1986/1987 at the Astronomical Observatory of A. Mickiewicz University, Poznan, with an astrograph of the F=1500 mm, d=300 mm.

  13. Astrographic Positions of Minor Planets

    NASA Astrophysics Data System (ADS)

    Nasrecki, W.; Swierkowska, S.

    The paper presents the photographic position of minor planets taken in the years 1985-1986 at the Astronomical Observatory of A. Mickiewicz University, Poznan, with a astrograph of the F=1500 mm, d=300 mm.

  14. Voyager to the Seventh Planet.

    ERIC Educational Resources Information Center

    Gold, Michael

    1986-01-01

    Presents recent findings obtained by the Voyager 2 mission on Uranus. Updates information on the planet's moons, rings, atmosphere, and magnetic field. Illustrations and diagrams of selected aspects of Uranus are included. (ML)

  15. Magnetospheres of the outer planets

    NASA Technical Reports Server (NTRS)

    Vanallen, James A.

    1987-01-01

    The five qualitatively different types of magnetism that a planet body can exhibit are outlined. Potential sources of energetic particles in a planetary magnetosphere are discussed. The magnetosphere of Uranus and Neptune are then described using Pioneer 10 data.

  16. Thermoelectric Outer Planets Spacecraft (TOPS)

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The research and advanced development work is reported on a ballistic-mode, outer planet spacecraft using radioisotope thermoelectric generator (RTG) power. The Thermoelectric Outer Planet Spacecraft (TOPS) project was established to provide the advanced systems technology that would allow the realistic estimates of performance, cost, reliability, and scheduling that are required for an actual flight mission. A system design of the complete RTG-powered outer planet spacecraft was made; major technical innovations of certain hardware elements were designed, developed, and tested; and reliability and quality assurance concepts were developed for long-life requirements. At the conclusion of its active phase, the TOPS Project reached its principal objectives: a development and experience base was established for project definition, and for estimating cost, performance, and reliability; an understanding of system and subsystem capabilities for successful outer planets missions was achieved. The system design answered long-life requirements with massive redundancy, controlled by on-board analysis of spacecraft performance data.

  17. Outer Planets - Duration: 71 seconds.

    NASA Video Gallery

    Did you know that through NASA’s various satellite missions we have learned more about these planetary bodies in recent years than we knew collectively since we started to study our planets? Throu...

  18. Planet X The current status

    NASA Astrophysics Data System (ADS)

    Seidelmann, P. K.; Harrington, R. S.

    1987-03-01

    Neptune and Pluto were discovered because of predictions derived from the differences between the observations and ephemerides of Uranus, but Pluto wasn't the predicted planet and the discrepancies still exist. This continuing existence of systematic differences between the observations and ephemerides of Uranus and Neptune has led to predictions of a Planet X. The demise of the dinosaurs and the existence of comets have been cited as additional evidence for another celestial object. Therefore, possible bodies have been hypothesized in the outer part of the solar system, or out beyond the solar system, including a binary companion, Nemesis. The theory of relativity and the incompleteness of the law of gravity have also been suggested as explanations for the outer planet discrepancies. Predictions of the possible locations of planet X have been made, with rather large uncertainties, and selected searches of some regions have yielded nothing. IRAS and Pioneer observations exist as additional sources of useful observational data.

  19. The evolution of ocean color

    NASA Astrophysics Data System (ADS)

    Gallardo, Victor A.; Espinoza, Carola

    2008-08-01

    Analog examples of what primeval oceans might have looked in the Precambrian are probably extant in various regions and at various size scales in present day oceans albeit they have not been sufficiently recognized and/or studied. The Eastern Boundary Current Ecosystems (EBCEs), with their characteristic high productivity-inducing coastal upwelling events, their extensive and intensive anoxic/hypoxic water column and methane and sulfide-rich benthic environment, appear to represent such analogs. Moreover, recent studies have shown that they possess diverse anaerobic prokaryotic communities of mat-forming large multi-cellular filamentous bacteria similar to fossils found in Archean and Proterozoic rocks. Observations in the Bay of Concepcion, central Chile (~36°S), inserted in the second most productive EBCE of the world, suggests that given similar oceanographic dynamics, past oceans may have presented different predominant colorations after the first probable "red" color of the reduced iron-rich Archean ocean and prior to the present day "blue" color. In this coastal ecosystem a "black" coloration has been observed to form as the result of the floating to the surface layer of sulfide-blackened benthic detritus together with chunks of microbial mats, and a "milky to turquoise" coloration resulting from different concentrations of colloidal, nano-sized particles which may include elemental sulfur and/or microorganisms. If the present is the key to the past we posit that "black" color oceans could have existed during the Proterozoic "Canfield sulfidic ocean" followed by "milky to turquoise" colored oceans during later stages of the Proterozoic. Meso-scale examples of "milky" and "turquoise" portions of oceans, caused by elemental sulfur from oxidized hydrogen sulfide eruptions, have been described from off Namibia and there appear to also exist elsewhere. Examples of "black" oceans have apparently not been reported but the name of the Black Sea, the largest permanent anoxic basin on Earth, suggests that at some point in time it may have been black, at least locally and/or for short periods, prompting the name. We conclude suggesting that analogous to the present "Blue Planet" denomination, in the past our Earth could possibly have deserved the successive names of "Red", "Black" and "Milky-Turquoise" Planet.

  20. Magnetic field of the planet Uranus: predictions, measurements, and interpretation

    SciTech Connect

    Dolginov, S.S.

    1987-09-01

    The magnitude and tilt of the eccentric dipole of Uranus are examined in the framework of a processing dynamo model. It is shown that the unique parameters of the magnetic field of Uranus are connected with the fact that, unlike the other planets, the magnetic field of Uranus is generated in two bordering regions whose highly conducting materials differ sharply in density: the density anti rho = 12 g x cm/sup -3/ in a core with an upper boundary r = 0.3R/sub U/, and anti rho = 3.1 g x cm/sup -3/ in an ocean with an upper boundary r = 0.6R/sub U/. The upper boundary of the magnetically active region in the ocean is determined by the magnetic pressure P = 1.9 Mbar, at which the ocean material is metallized.

  1. Popular Education As Adult Education within Postmodernism.

    ERIC Educational Resources Information Center

    Stanage, Sherman M.

    1995-01-01

    Adult education must become popular education in both communal and personal terms to survive funding agencies' special power-interest hegemonies, traditional higher education models, and rampant economic materialism. This article discusses six modernist constructions of adult education, highlighting professionalization and specialization, and…

  2. Lyrical Commentaries: Learning from Popular Music.

    ERIC Educational Resources Information Center

    Cooper, B. Lee

    1991-01-01

    Depicts ways popular song lyrics can stimulate discussion either in music, social studies, humanities, or language arts classes. Considers lyrics' ability to explain social, cultural, and political phenomena. Provides a chronological outline from 1962 correlating political events, personalities, songs, and the artists. songs. Identifies uses of…

  3. Teaching Theory through Popular Culture Texts

    ERIC Educational Resources Information Center

    Trier, James

    2007-01-01

    In this article, the author describes a pedagogical approach to teaching theory to pre-service teachers. This approach involves articulating academic texts that introduce theoretical ideas and tools with carefully selected popular culture texts that can be taken up to illustrate the elements of a particular theory. Examples of the theories…

  4. Using Popular Children's Films in Science

    ERIC Educational Resources Information Center

    Wadsworth, Elle; Croker, Stev; Harrison, Tim

    2012-01-01

    Watching films is a common activity for children outside of school, and incorporating popular films that contain scientific references has the potential to spark interest in the classroom. Clips rather than entire films can be used, as the children will maintain focus on the lesson objectives while being excited by the appeal of the film. The use…

  5. Bolivian Currents: Popular Participation and Indigenous Communities.

    ERIC Educational Resources Information Center

    Dudley, Mary Jo

    1997-01-01

    Describes the effects on indigenous communities of Bolivia's recent Popular Participation Laws, which relocated political and financial decision making to the municipal level; community efforts toward cultural maintenance and nonformal agricultural education; the activism of indigenous university students; and the dual discrimination suffered by…

  6. The Guide to Teaching with Popular Music.

    ERIC Educational Resources Information Center

    Music Educators National Conference, Reston, VA.

    Popular music is often characterized as a short work with a prominent melody and simple chordal accompaniment. Yet, teaching with pop music in the era of standards-based curriculum can present challenges. These standards offer teachers a blueprint for teaching music performance, composition, improvisation, and the relationship of music to other…

  7. Predicting Bullying: Maladjustment, Social Skills and Popularity

    ERIC Educational Resources Information Center

    Postigo, Silvia; Gonzalez, Remedios; Mateu, Carmen; Montoya, Inmaculada

    2012-01-01

    In order to prevent bullying, research has characterised the adolescents involved in terms of their social skills, maladjustment and popularity. However, there is a lack of knowledge concerning the relationships between these variables and how these relationships predict bullying involvement. Moreover, the literature has focused on pure bullies

  8. Popular Literature: Its Compatibility with the Basics.

    ERIC Educational Resources Information Center

    Matthews, Dorothy, Ed.

    1983-01-01

    This special journal issue contains nine articles on the subject of using popular literature in the classroom. Subjects covered in the articles include (1) using vernacular supernatural literature to teach the skills of literary analysis, (2) teaching Agatha Christie's "Curtain," (3) pairing the classics with detective fiction, (4) using fantasy…

  9. American Popular Music 1950-2000

    ERIC Educational Resources Information Center

    Lonergan, David

    2011-01-01

    This article describes and discusses some of the chief resources in the study of post-World War II mainstream popular music. In addition to indicating major areas of research, it can serve as a guide to collection development in the discipline.

  10. Predicting Bullying: Maladjustment, Social Skills and Popularity

    ERIC Educational Resources Information Center

    Postigo, Silvia; Gonzalez, Remedios; Mateu, Carmen; Montoya, Inmaculada

    2012-01-01

    In order to prevent bullying, research has characterised the adolescents involved in terms of their social skills, maladjustment and popularity. However, there is a lack of knowledge concerning the relationships between these variables and how these relationships predict bullying involvement. Moreover, the literature has focused on pure bullies…

  11. Forecasting Popularity of Videos Using Social Media

    NASA Astrophysics Data System (ADS)

    Xu, Jie; van der Schaar, Mihaela; Liu, Jiangchuan; Li, Haitao

    2015-03-01

    This paper presents a systematic online prediction method (Social-Forecast) that is capable to accurately forecast the popularity of videos promoted by social media. Social-Forecast explicitly considers the dynamically changing and evolving propagation patterns of videos in social media when making popularity forecasts, thereby being situation and context aware. Social-Forecast aims to maximize the forecast reward, which is defined as a tradeoff between the popularity prediction accuracy and the timeliness with which a prediction is issued. The forecasting is performed online and requires no training phase or a priori knowledge. We analytically bound the prediction performance loss of Social-Forecast as compared to that obtained by an omniscient oracle and prove that the bound is sublinear in the number of video arrivals, thereby guaranteeing its short-term performance as well as its asymptotic convergence to the optimal performance. In addition, we conduct extensive experiments using real-world data traces collected from the videos shared in RenRen, one of the largest online social networks in China. These experiments show that our proposed method outperforms existing view-based approaches for popularity prediction (which are not context-aware) by more than 30% in terms of prediction rewards.

  12. Popular Education and the Logics of Schooling

    ERIC Educational Resources Information Center

    Rockwell, Elsie

    2011-01-01

    In this article, I compare two distinct uses of "Popular Education" that emerged in Tlaxcala in the wake of the Mexican Revolution. I examine archival and oral evidence to reconstruct the situated meanings and political rationales that led to the use of the term in each case, beyond their contrasting pedagogical content. In 1917, a revolutionary…

  13. Popular Media and the Teenage Sexual Agenda.

    ERIC Educational Resources Information Center

    Strover, Sharon

    A qualitative study examined how teenagers react to and interpret certain popular media messages. In addition it explored the relationship between content containing various sexual messages and teenagers' responses to those messages, with particular attention to the critical abilities this audience exhibits. Fifty male and female teenagers aged…

  14. Popular Education As Adult Education within Postmodernism.

    ERIC Educational Resources Information Center

    Stanage, Sherman M.

    1995-01-01

    Adult education must become popular education in both communal and personal terms to survive funding agencies' special power-interest hegemonies, traditional higher education models, and rampant economic materialism. This article discusses six modernist constructions of adult education, highlighting professionalization and specialization, and

  15. Popular Literature: Its Compatibility with the Basics.

    ERIC Educational Resources Information Center

    Matthews, Dorothy, Ed.

    1983-01-01

    This special journal issue contains nine articles on the subject of using popular literature in the classroom. Subjects covered in the articles include (1) using vernacular supernatural literature to teach the skills of literary analysis, (2) teaching Agatha Christie's "Curtain," (3) pairing the classics with detective fiction, (4) using fantasy

  16. [Lawyers and Litigation in the Popular Culture.

    ERIC Educational Resources Information Center

    Ryan, John Paul, Ed.

    1991-01-01

    This issue of Focus on Law Studies contains the following articles: "T.V. Law: Image versus Reality" (Suzanne Frentz); "Teaching about Civil Rights in the 1990's" (Cynthia Hamilton); "A Social History of Black Lawyers in Popular Culture" (Ric Sheffield); "Will the Real Lawyers Please Stand Up!" (Susan Adair Dwyer-Shick); "Equality, 'Political…

  17. Memory for Frequency of Hearing Popular Music.

    ERIC Educational Resources Information Center

    Fidler, James R.; And Others

    This experiment was designed to better understand the effects of individual differences, intent to learn, and stimulus familiarity on frequency judgment accuracy. Half of the participants in the study heard popular songs, and the other half listened to unfamiliar songs. Participants were subdivided into three more groups, introducing the "intent…

  18. Popular Education and the "Party Line"

    ERIC Educational Resources Information Center

    Boughton, Bob

    2013-01-01

    Popular education, by which is meant adult education within and in support of radical social movements, has become a major topic in academic adult education in recent times. This paper criticises the lack of attention paid in most of this writing to the history, theory and practice of revolutionary parties in the communist and socialist tradition.…

  19. Misreading Masculinity: Boys, Literacy, and Popular Culture.

    ERIC Educational Resources Information Center

    Newkirk, Thomas

    This book takes an up-close and personal look at elementary school boys and their relationship to sports, movies, video games, and other avenues of popular culture. The book views these media not as enemies of literacy, but as resources "for" literacy. It contains a series of interviews with young boys and girls who describe the pleasure they take…

  20. Misreading Masculinity: Boys, Literacy, and Popular Culture.

    ERIC Educational Resources Information Center

    Newkirk, Thomas

    This book takes an up-close and personal look at elementary school boys and their relationship to sports, movies, video games, and other avenues of popular culture. The book views these media not as enemies of literacy, but as resources "for" literacy. It contains a series of interviews with young boys and girls who describe the pleasure they take

  1. Popular Financial Reports: Accountability through Readability.

    ERIC Educational Resources Information Center

    Anderson, Richard T.; Piotrowski, Craig L.

    1994-01-01

    Discusses colleges' use of popular financial reporting to make their annual financial reports more readable to citizens and legislators and to make their reports useful marketing and recruitment tools. Highlights research about financial reports and performance reporting conducted by the Governmental Accounting Standards Board. Describes the…

  2. Caveat Lector: Reviewing Popular Social Science.

    ERIC Educational Resources Information Center

    Hixson, Vivian Scott

    1981-01-01

    Discusses problems with reviews and criticisms of popular social science books: the quality and background of reviewers, the difficulty of distinguishing between fact and opinion, and the scarcity of competent reviewers. Analyzes reviews of Robert Ardrey's "African Genesis" and "The Territorial Imperative," Konrad Lorenz's "On Aggression," and…

  3. Is Being Popular a Risky Proposition?

    ERIC Educational Resources Information Center

    Mayeux, Lara; Sandstrom, Marlene J.; Cillessen, Antonius H. N.

    2008-01-01

    Longitudinal associations between social preference, perceived popularity, and risk behaviors (smoking, alcohol use, and sexual activity) were examined in a sample of high school students. Social preference did not predict any of the risk behaviors assessed, although the interaction between gender and social preference was predictive of sexual…

  4. Teaching Theory through Popular Culture Texts

    ERIC Educational Resources Information Center

    Trier, James

    2007-01-01

    In this article, the author describes a pedagogical approach to teaching theory to pre-service teachers. This approach involves articulating academic texts that introduce theoretical ideas and tools with carefully selected popular culture texts that can be taken up to illustrate the elements of a particular theory. Examples of the theories

  5. UWP 011: Popular Science and Technology Writing

    ERIC Educational Resources Information Center

    Perrault, Sarah

    2012-01-01

    UWP 011: Popular Science & Technology Writing is a sophomore-level course designed as an introduction to rhetoric of science at UC Davis, a science-focused land-grant university. The course fulfills the general education requirements for written literacy and for topical breadth in arts and humanities. The catalog describes the course as…

  6. Stepfamily Strengths: A Review of Popular Literature.

    ERIC Educational Resources Information Center

    Coleman, Marilyn; And Others

    1985-01-01

    Reviewed popular literature (self-help books, magazines, adolescent fiction) that identified stepfamily strengths. Potential strengths of stepfamily life were identified in all three sources. The primary focus of self-help literature and magazine articles, however, was on stepfamily problems. Concludes that adolescent fiction may be used to good…

  7. Understanding and Developing Black Popular Music Collections.

    ERIC Educational Resources Information Center

    Murray, James Briggs

    1983-01-01

    Enumerates types of black popular music (work songs, spirituals, gospel music, blues, race records, rock and roll, soul, funk, disco, Caribbean, and African) and discusses collection development (current, retrospective, monographs, periodicals, sheet music, motion picture film, photographs, oral history), cataloging, and preservation. A 229-item…

  8. Gender and Cultural Consecration in Popular Music

    ERIC Educational Resources Information Center

    Schmutz, Vaughn; Faupel, Alison

    2010-01-01

    This research examines the gendered nature of cultural legitimacy and consecration in popular music. We explore two related questions. First, which factors affect the likelihood that female performers achieve consecrated status? Second, how are those decisions discursively legitimated? Using a mixed-methods research design, we find that in both…

  9. What Is Popular Music Studies? Some Observations

    ERIC Educational Resources Information Center

    Cloonan, Martin

    2005-01-01

    Popular Music Studies (PMS) is now taught in over 20 higher education institutions (HEIs) in the UK and numerous others across the world. This article outlines the constituent parts of PMS in the UK and questions its status as a discipline in its own right. It concludes by arguing that, having established itself, PMS will need to deal with two key…

  10. A Comparison of "Popular Music Pedagogy" Discourses

    ERIC Educational Resources Information Center

    Mantie, Roger

    2013-01-01

    The purpose of this study was to interrogate discourses of "popular music pedagogy" in order to better understand music education practices generally and specifically those in the United States. Employing a conceptual framework based on the work of Jan Blommaert (2005), a content analysis was conducted on a sample of 81 articles related…

  11. Planet Hunters: Kepler by Eye

    NASA Astrophysics Data System (ADS)

    Schwamb, Megan E.; Lintott, C.; Fischer, D.; Smith, A. M.; Boyajian, T. S.; Brewer, J. M.; Giguere, M. J.; Lynn, S.; Parrish, M.; Schawinski, K.; Schmitt, J.; Simpson, R.; Wang, J.

    2014-01-01

    Planet Hunters (http://www.planethunters.org), part of the Zooniverse's (http://www.zooniverse.org) collection of online citizen science projects, uses the World Wide Web to enlist the general public to identify transits in the pubic Kepler light curves. Planet Hunters utilizes human pattern recognition to identify planet transits that may be missed by automated detection algorithms looking for periodic events. Referred to as ‘crowdsourcing’ or ‘citizen science’, the combined assessment of many non-expert human classifiers with minimal training can often equal or best that of a trained expert and in many cases outperform the best machine-learning algorithm. Visitors to the Planet Hunters' website are presented with a randomly selected ~30-day light curve segment from one of Kepler’s ~160,000 target stars and are asked to draw boxes to mark the locations of visible transits in the web interface. 5-10 classifiers review each 30-day light curve segment. Since December 2010, more than 260,000 volunteers world wide have participated, contributing over 20 million classifications. We have demonstrated the success of a citizen science approach with the project’s more than 20 planet candidates, the discovery of PH1b, a transiting circumbinary planet in a quadruple star system, and the discovery of PH2-b, a confirmed Jupiter-sized planet in the habitable zone of a Sun-like star. I will provide an overview of Planet Hunters, highlighting several of project's most recent exoplanet and astrophysical discoveries. Acknowledgements: MES was supported in part by a NSF AAPF under award AST-1003258 and a American Philosophical Society Franklin Grant. We acknowledge support from NASA ADAP12-0172 grant to PI Fischer.

  12. G. P. Kuiper's Early Studies of Planets

    NASA Astrophysics Data System (ADS)

    Cruikshank, D. P.

    2005-08-01

    Gerard P. Kuiper was born on December 7, 1905; this is his centennial year. While he had an early interest in Solar System bodies, writing an extensive review about Mars for the popular Dutch astronomy journal, Hemel en Dampkring in 1931, Kuiper's first important observations began in 1944, when he discovered the atmosphere of Titan. In a letter dated February 29, 1944, to Lick Observatory director Joseph H. Moore, Kuiper noted that, ``The only reason I happened to observe the planets and the 10 brightest satellites was that they were nicely lined up in a region of the sky where I had run out of program stars (stars of large proper motion and parallax)." These spectroscopic observations were obtained with the new McDonald 82-inch telescope during a break from Kuiper's war-time work at Harvard's Radio Research Laboratory. In a letter of congratulations, his friend S. Chandrasekhar wrote, ``It is only on the impact of such discoveries that one realizes afresh the permanent value of science which no war -- not even of Hitler's -- can truly undermine. And it must be of satisfaction to you that if you took a vacation from war-work, it was only to make a fundamental discovery!" Using detectors declassified at the end of World War II, Kuiper began a study of the infrared spectra of planets and stars (with the first publication in 1947) that continued to the time of his death (December 24, 1973). Early in this work, on March 2, 1948, he wrote a lengthy letter to Henry Norris Russell in which he succinctly and enthusiastically summarized his observations and discoveries. Details in this letter give a fascinating perspective on some of the earliest physical studies of Solar System bodies, such as the detection of water ice on Saturn's rings and in the polar cap of Mars, spectral and photometric measurements of Mars' surface and atmospheric haze, and the discovery of Miranda.

  13. The Earth is a Planet Too!

    NASA Technical Reports Server (NTRS)

    Cairns, Brian

    2014-01-01

    When the solar system formed, the sun was 30 dimmer than today and Venus had an ocean. As the sun brightened, a runaway greenhouse effect caused the Venus ocean to boil away. At times when Earth was younger, the sun less bright, and atmospheric CO2 less, Earth froze over (snowball Earth). Earth is in the sweet spot today. Venus is closer to sun than Earth is, but cloud-covered Venus absorbs only 25 of incident sunlight, while Earth absorbs 70. Venus is warmer because it has a thick carbon dioxide atmosphere causing a greenhouse effect of several hundred degrees. Earth is Goldilocks choice among the planets, the one that is just right for life to exist. Not too hot. Not too cold. How does the Earth manage to stay in this habitable range? Is there a Gaia phenomenon keeping the climate in bounds? A nice idea, but it doesnt work. Today, greenhouse gas levels are unprecedented compared to the last 450,000 years.

  14. Shallow Cavities in Multiple-planet Systems

    NASA Astrophysics Data System (ADS)

    Duffell, Paul C.; Dong, Ruobing

    2015-03-01

    Large cavities are often observed in protoplanetary disks, which might suggest the presence of planets opening gaps in the disk. Multiple planets are necessary to produce a wide cavity in the gas. However, multiple planets may also be a burden to the carving out of very deep gaps. When additional planets are added to the system, the time-dependent perturbations from these additional satellites can stir up gas in the gap, suppressing cavity opening. In this study, we perform two-dimensional numerical hydro calculations of gap opening for single and multiple planets, showing the effect that additional planets have on the gap depths. We show that multiple planets produce much shallower cavities than single planets, so that more massive planets are needed in the multiple-planet case to produce an equivalent gap depth as in the single-planet case. To deplete a gap by a factor of 100 for the parameters chosen in this study, one only requires Mp ≈ 3.5 MJ in the single-planet case, but much more massive planets, Mp ≈ 7 MJ are required in the multiple-planet case. This requirement of high-mass planets implies that such planets may be detectable in the next generation of direct imaging projects, in gaps whose depths are constrained to be sufficiently deep by ALMA.

  15. Polarisation of Planets and Exoplanets

    NASA Astrophysics Data System (ADS)

    Bailey, Jeremy; Kedziora-Chudczer, Lucyna; Bott, Kimberly; Cotton, Daniel V.

    2015-11-01

    We present observations of the linear polarisation of several hot Jupiter systems with our new high-precision polarimeter HIPPI (HIgh Precision Polarimetric Instrument). By looking at the combined light of the star and planet we aim to detect the polarised light reflected from the planet's atmosphere. This can provide information on the presence of, and nature of clouds in the atmosphere, and constrain the geometric albedo of the planet. The method is applicable to both transitting and non-transitting planets, and can also be used to determine the inclination of the system, and thus the true mass for radial velocity detected planets.To predict and interpret the polarisation from such observations, we have also developed an advanced polarimetric modelling capability, by incoroporating full polarised radiative transfer into our atmospheric modelling code VSTAR. This is done using the VLIDORT vector radiative transfer solver (Spurr, 2006). The resulting code allows us to predict disc-resolved, phase-resolved, and spectrally-resolved intensity and linear polarisation for any planet, exoplanet, brown dwarf or cool star atmosphere that can be modelled with VSTAR. We have tested the code by reproducing benchmark calculations in polarised radiative transfer, and by Solar System test cases, including reproducing the classic Hansen and Hovenier (1974) calculation of the polarisation phase curves of Venus.Hansen, J.E., & Hovenier, J.W., 1974, J. Atmos. Sci., 31, 1137Spurr, R., 2006, JQSRT, 102, 316.

  16. Planets in extreme magnetic environments

    NASA Astrophysics Data System (ADS)

    Moutou, Claire

    2015-12-01

    Interactions between stars and planets in very close-in systems include irradiation, tidal and magnetic effects, the relative amplitudes of which depend on the system parameters. The extent of magnetic interactions, however, is only poorly known since the magnetic fields of the parent star itself is barely characterized. In this presentation, I will review the recent efforts made to measure and characterize the magnetic fields of star hosting close-in planets, in order to provide quantitative constraints in the studies of star-planet interactions.We have been using the spectropolarimeters CFHT/ESPaDOnS and TBL/NARVAL to assess the our ability to detect the circular polarization of several dozens planet-host stars, and to map the large-scale magnetic topology of a sub-sample of these stars. The detection of magnetic fields as low as a few Gauss is possible around relatively bright, solar-like stars. After hot-Jupiter systems, we got interested in systems with smaller planets in close orbits. Several applications of these magnetic topologies have already been used in theoretical analyses of the star-planet interactions, that we will briefly review. Perspectives for this work include further observing programs and more detailed theoretical representations.

  17. Kuiper Prize: Giant Planet Atmospheres

    NASA Astrophysics Data System (ADS)

    Ingersoll, Andrew P.

    2007-10-01

    The study of giant planet atmospheres is near and dear to me, for several reasons. First, the giant planets are photogenic; the colored clouds are great tracers, and one can make fantastic movies of the atmosphere in motion. Second, the giant planets challenge us with storms that last for hundreds of years and winds that blow faster the farther you go from the sun. Third, they remind us of Earth with their hurricanes, auroras, and lightning, but they also are the link to the 200 giant planets that have been discovered around other stars. This talk will cover the past, present, and future (one hopes) of giant planet research. I will review the surprises of the Voyager and Galileo eras, and will discuss what we are learning now from the Cassini orbiter. I will review the prospects for answering the outstanding questions like: Where's the water? What is providing the colors of the clouds? How deep do the features extend? Where do the winds get their energy? What is the role of the magnetic field? Finally, I will briefly discuss how extrasolar giant planets compare with objects in our own solar system.

  18. Habitable Planets with High Obliquities

    NASA Astrophysics Data System (ADS)

    Williams, D. M.; Kasting, J. F.

    1996-03-01

    The obliquities of the terrestrial planets have been shown to vary chaotically and by large amounts in times less than 10 Myr, thus inviting the possibility for Earth to occasionally reach high obliquity where it might experience climatic conditions unfavorable for life. Although Earth escapes this fate by having its rotation axis stabilized by the Moon, many extrasolar Earth-like planets without large satellites should be subjected to periods of high obliquity. The number of worlds supporting life outside the Solar System, then, may be far fewer than has been suggested if high obliquities render moon-less Earths uninhabitable. Climates at high obliquity are particularly harsh on middle and high latitude continents that warm and cool rapidly in response to large insolation swings. These areas exhibit a wide range of temperatures over a seasonal cycle, with extremes reaching well above or below 273 Kelvin, making them seasonally unsuitable for water-dependent life. We demonstrate here that Earth-like planets will have their temperature extremes mitigated at high obliquity if they possess dense CO2 atmospheres, as is likely for many planets situated in the outer habitable zone (HZ) of a Sun-like star. The climate stabilizing mechanism governing atmospheric CO2 on Earth-like planets is carbonate-silicate weathering. Planets with atmospheres rich in CO2 demonstrate small latitudinal temperature gradients and seasonal temperature cycles, and thus remain habitable at high obliquities.

  19. Planetary Systems and the Formation of Habitable Planets

    NASA Astrophysics Data System (ADS)

    Dvorak, Rudolf; Maindl, Thomas I.; Burger, Christoph; Schäfer, Christoph; Speith, Roland

    2015-09-01

    As part of a national scientific network 'Pathways to Habitability' the formation of planets and the delivery of water onto these planets is a key question as water is essential for the development of life. In the first part of the paper we summarize the state of the art of planet formation - which is still under debate in the astronomical community - before we show our results on this topic. The outcome of our numerical simulations depends a lot on the choice of the initial distribution of planetesimals and planetary embryos after gas disappeared in the protoplanetary disk. We also take into account that some of these planetesimals of sizes in the order of the mass of the Moon already contained water; the quantity depends on the distance from the Sun - close-by bodies are dry, but starting from a distance of about 2 AU they can contain substantial amounts of water. We assume that the gas giants and terrestrial planets are already formed when we check the collisions of the small bodies containing water (in the order of a few percent) with the terrestrial planets. We thus are able to give an estimate of the respective contribution to the actual water content (of some Earth-oceans) in the mantle, in the crust and on the surface of Earth. In the second part we discuss in more detail how the formation of larger bodies after a collision may happen as the outcome depends on parameters like collision velocity, impact angle, and the materials involved. We present results obtained by SPH (Smooth Particle Hydrodynamics) simulations. We briefly describe this method and show different scenarios with respect to the formed bodies, possible fragmentation and the water content before and after the collision. In an appendix we discuss detection methods for extrasolar planets (close to 2000 such objects have been discovered so far).

  20. Planet Earth: Its Past, Our Present, A Future (?)

    NASA Astrophysics Data System (ADS)

    Kieffer, S. W.

    2012-04-01

    We who have lived through the second half of the 20th century into the 21st century have witnessed a profound transition in the biological and physical relationship between humans and the rest of the planet. In the middle of the last century, our planet still had undeveloped islands: there were frontiers that held new lands, mysteries, adventures, cultures, and resources. However, these islands have merged into a relatively seamless planet by a mobile and expanding population, science and technology, and global communication. We are subject to stealth as well as natural disasters. Natural disasters result from the ongoing geological and meteorological processes on our planet, increasingly exacerbated by human presence and behavior. Stealth disasters, on the other hand, are caused by humans, but involve the natural systems that support us. Examples of stealth disasters are climate change, loss of soils, acidification of the oceans, desertification, and loss of groundwater resources. Civilization is a complex system. It has emergent properties, and a tuning parameter--a parameter that is "tuned" until the unexpected happens. The tuning parameter for populations is the number of members relative to the capacities that support them. Because of our sheer numbers, we are driving the stealth disasters, and we will be affected more severely by natural disasters than we have been in the past on a less densely populated planet. To guide our thinking about geoethical issues, we propose a (hypothetical) world organization modeled after the Centers for Disease Control (CDC) in the U.S., and call it the Center for Disaster Control for Planet Earth (CDCPE). This center would have a scientific body to provide impartial facts and uncertainties, an engineering body to propose and implement technical solutions, a negotiating body to balance the realities of political, economic, religious and cultural values, and an enforcement body that is responsive to all of the inputs. How shall we start?

  1. The atmospheres of earthlike planets after giant impact events

    SciTech Connect

    Lupu, R. E.; Freedman, Richard; Schaefer, Laura; Morley, Caroline; Fortney, Jonathan J.; Cahoy, Kerri

    2014-03-20

    It is now understood that the accretion of terrestrial planets naturally involves giant collisions, the moon-forming impact being a well-known example. In the aftermath of such collisions, the surface of the surviving planet is very hot and potentially detectable. Here we explore the atmospheric chemistry, photochemistry, and spectral signatures of post-giant-impact terrestrial planets enveloped by thick atmospheres consisting predominantly of CO{sub 2} and H{sub 2}O. The atmospheric chemistry and structure are computed self-consistently for atmospheres in equilibrium with hot surfaces with composition reflecting either the bulk silicate Earth (which includes the crust, mantle, atmosphere, and oceans) or Earth's continental crust. We account for all major molecular and atomic opacity sources including collision-induced absorption. We find that these atmospheres are dominated by H{sub 2}O and CO{sub 2}, while the formation of CH{sub 4} and NH{sub 3} is quenched because of short dynamical timescales. Other important constituents are HF, HCl, NaCl, and SO{sub 2}. These are apparent in the emerging spectra and can be indicative that an impact has occurred. The use of comprehensive opacities results in spectra that are a factor of two lower brightness temperature in the spectral windows than predicted by previous models. The estimated luminosities show that the hottest post-giant-impact planets will be detectable with near-infrared coronagraphs on the planned 30 m class telescopes. The 1-4 μm will be most favorable for such detections, offering bright features and better contrast between the planet and a potential debris disk. We derive cooling timescales on the order of 10{sup 5-6} yr on the basis of the modeled effective temperatures. This leads to the possibility of discovering tens of such planets in future surveys.

  2. The Atmospheres of Earthlike Planets after Giant Impact Events

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

    It is now understood that the accretion of terrestrial planets naturally involves giant collisions, the moon-forming impact being a well-known example. In the aftermath of such collisions, the surface of the surviving planet is very hot and potentially detectable. Here we explore the atmospheric chemistry, photochemistry, and spectral signatures of post-giant-impact terrestrial planets enveloped by thick atmospheres consisting predominantly of CO2 and H2O. The atmospheric chemistry and structure are computed self-consistently for atmospheres in equilibrium with hot surfaces with composition reflecting either the bulk silicate Earth (which includes the crust, mantle, atmosphere, and oceans) or Earth's continental crust. We account for all major molecular and atomic opacity sources including collision-induced absorption. We find that these atmospheres are dominated by H2O and CO2, while the formation of CH4 and NH3 is quenched because of short dynamical timescales. Other important constituents are HF, HCl, NaCl, and SO2. These are apparent in the emerging spectra and can be indicative that an impact has occurred. The use of comprehensive opacities results in spectra that are a factor of two lower brightness temperature in the spectral windows than predicted by previous models. The estimated luminosities show that the hottest post-giant-impact planets will be detectable with near-infrared coronagraphs on the planned 30 m class telescopes. The 1-4 μm will be most favorable for such detections, offering bright features and better contrast between the planet and a potential debris disk. We derive cooling timescales on the order of 105-6 yr on the basis of the modeled effective temperatures. This leads to the possibility of discovering tens of such planets in future surveys.

  3. Homes for extraterrestrial life: extrasolar planets.

    PubMed

    Latham, D W

    2001-12-01

    Astronomers are now discovering giant planets orbiting other stars like the sun by the dozens. But none of these appears to be a small rocky planet like the earth, and thus these planets are unlikely to be capable of supporting life as we know it. The recent discovery of a system of three planets is especially significant because it supports the speculation that planetary systems, as opposed to single orbiting planets, may be common. Our ability to detect extrasolar planets will continue to improve, and space missions now in development should be able to detect earth-like planets. PMID:11797754

  4. Convection and plate tectonics on extrasolar planets

    NASA Astrophysics Data System (ADS)

    Sotin, C.; Grasset, O.; Schubert, G.

    2012-04-01

    The number of potential Earth-like exoplanets is still very limited compared to the overall number of detected exoplanets. But the different methods keep improving, giving hope for this number to increase significantly in the coming years. Based on the relationship between mass and radius, two of the easiest parameters that can be known for exoplanets, four categories of planets have been identified: (i) the gas giants including hot Jupiters, (ii) the icy giants that can be like their solar system cousins Uranus and Neptune or that can have lost their H2-He atmosphere and have become the so-called ocean planets, (iii) the Earth-like planets with a fraction of silicates and iron similar to that of the Earth, and (iv) the Mercury like planet that have a much larger fraction of iron. The hunt for exoplanets is very much focused on Earth-like planets because of the desire to find alien forms of life and the science goal to understand how life started and developed on Earth. One science question is whether heat transfer by subsolidus convection can lead to plate tectonics, a process that allows material to be recycled in the interior on timescales of hundreds of millions of years. Earth-like exoplanets may have conditions quite different from Earth. For example, COROT-7b is so close to its star that it is likely locked in synchronous orbit with one very hot hemisphere and one very cold hemisphere. It is also worth noting that among the three Earth-like planets of the solar system (Earth, Venus and Mars), only Earth is subject to plate tectonics at present time. Venus may have experienced plate tectonics before the resurfacing event that erased any clue that such a process existed. This study investigates some of the parameters that can influence the transition from stagnant-lid convection to mobile-lid convection. Numerical simulations of convective heat transfer have been performed in 3D spherical geometry in order to determine the stress field generated by convection processes in the cold thermal boundary layer that lies under the stagnant lid. Different boundary conditions have been investigated such as the surface temperature, the core temperature, the viscosity of the mantle, and the amount of internal heating. A total of 18 numerical simulations have been carried out from which scaling laws describing the shear stresses affecting the stagnant lid have been have been deduced. Their application to Earth-like exoplanets will be discussed. Different viscous laws have also been investigated. Preliminary results suggest that non-Newtonian deformation favors the transition from stagnant lid to mobile lid. Finally, application to large icy moons and icy giants is being investigated. Part of this work has been performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA. Government sponsorship acknowledged.

  5. A new view on planet formation

    NASA Astrophysics Data System (ADS)

    Nayakshin, Sergei

    2011-11-01

    The standard picture of planet formation posits that giant gas planets are over-grown rocky planets massive enough to attract enormous gas atmospheres. It has been shown recently that the opposite point of view is physically plausible: the rocky terrestrial planets are former giant planet embryos dried of their gas ``to the bone'' by the influences of the parent star. Here we provide a brief overview of this ``Tidal Downsizing'' hypothesis in the context of the Solar System structure.

  6. Ocean dumping

    SciTech Connect

    Not Available

    1982-01-01

    The regulation of the dumping of materials into the ocean is reviewed. Criteria to be applied in reviewing and evaluating permit applications for the transportation and dumping of materials into the ocean are established. A definition of monitoring of dumping sites, the assessment of fees to cover permit processing costs, and a moratorium is placed on the issuance of permits for the disposal of radioactive waste are included.

  7. Terraforming planet Dune: Climate-vegetation interactions on a sandy planet

    NASA Astrophysics Data System (ADS)

    Cresto Aleina, F.; Baudena, M.; D'Andrea, F.; Provenzale, A.

    2012-04-01

    The climate and the biosphere of planet Earth interact in multiple, complicated ways and on many spatial and temporal scales. Some of these processes can be studied with the help of simple mathematical models, as done for the effects of vegetation on albedo in desert areas and for the mechanisms by which terrestrial vegetation affects water fluxes in arid environments. Conceptual models of this kind do not attempt at providing quantitative descriptions of the climate-biosphere interaction, but rather to explore avenues and mechanisms which can play a role in the real system, providing inspiration for further research. In this work, we develop a simple conceptual box model in the spirit illustrated above, to explore whether and how vegetation affects the planetary hydrologic cycle. We imagine a planet with no oceans and whose surface is entirely covered with sand, quite similar to planet Dune of the science-fiction series by Frank Herbert (1965). We suppose that water is entirely in the sand, below the surface. Without vegetation, only evaporation takes place, affecting the upper sand layer for a maximum depth of a few cm. The amount of water that is evaporated in the atmosphere is relatively small, and not sufficient to trigger a full hydrologic cycle. The question is what happens to this planet when vegetation is introduced: the root depth can reach a meter or more, and plant transpiration can then transfer a much larger amount of water to the atmosphere. One may wonder whether the presence of vegetation is sufficient to trigger a hydrologic cycle with enough precipitation to sustain the vegetation itself and, if the answer is positive, what is the minimum vegetation cover that is required to maintain the cycle active. In more precise terms, we want to know whether the introduction of vegetation and of the evapotranspiration feedback allows for the existence of multiple equilibria (or solutions) in the soil-vegetation-atmosphere system. Although the box model introduced here is best formulated in terms of a hypothetical sandy planet, the results can be used to study the hydrologic cycle on wide continental regions of the Earth. On the other hand, our findings show how the definition of a habitable climate may also depend on surface characteristics, and in particular on biosphere and climate interactions.

  8. Giant Planets Orbiting Metal-rich Stars Show Signatures of Planet-Planet Interactions

    NASA Astrophysics Data System (ADS)

    Dawson, Rebekah I.; Murray-Clay, Ruth A.

    2013-04-01

    Gas giants orbiting interior to the ice line are thought to have been displaced from their formation locations by processes that remain debated. Here we uncover several new metallicity trends, which together may indicate that two competing mechanisms deliver close-in giant planets: gentle disk migration, operating in environments with a range of metallicities, and violent planet-planet gravitational interactions, primarily triggered in metal-rich systems in which multiple giant planets can form. First, we show with 99.1% confidence that giant planets with semimajor axes between 0.1 and 1 AU orbiting metal-poor stars ([Fe/H] < 0) are confined to lower eccentricities than those orbiting metal-rich stars. Second, we show with 93.3% confidence that eccentric proto-hot Jupiters undergoing tidal circularization primarily orbit metal-rich stars. Finally, we show that only metal-rich stars host a pile-up of hot Jupiters, helping account for the lack of such a pile-up in the overall Kepler sample. Migration caused by stellar perturbers (e.g., stellar Kozai) is unlikely to account for the trends. These trends further motivate follow-up theoretical work addressing which hot Jupiter migration theories can also produce the observed population of eccentric giant planets between 0.1 and 1 AU.

  9. GIANT PLANETS ORBITING METAL-RICH STARS SHOW SIGNATURES OF PLANET-PLANET INTERACTIONS

    SciTech Connect

    Dawson, Rebekah I.; Murray-Clay, Ruth A.

    2013-04-20

    Gas giants orbiting interior to the ice line are thought to have been displaced from their formation locations by processes that remain debated. Here we uncover several new metallicity trends, which together may indicate that two competing mechanisms deliver close-in giant planets: gentle disk migration, operating in environments with a range of metallicities, and violent planet-planet gravitational interactions, primarily triggered in metal-rich systems in which multiple giant planets can form. First, we show with 99.1% confidence that giant planets with semimajor axes between 0.1 and 1 AU orbiting metal-poor stars ([Fe/H] < 0) are confined to lower eccentricities than those orbiting metal-rich stars. Second, we show with 93.3% confidence that eccentric proto-hot Jupiters undergoing tidal circularization primarily orbit metal-rich stars. Finally, we show that only metal-rich stars host a pile-up of hot Jupiters, helping account for the lack of such a pile-up in the overall Kepler sample. Migration caused by stellar perturbers (e.g., stellar Kozai) is unlikely to account for the trends. These trends further motivate follow-up theoretical work addressing which hot Jupiter migration theories can also produce the observed population of eccentric giant planets between 0.1 and 1 AU.

  10. Inside-Out Planet Formation

    NASA Astrophysics Data System (ADS)

    Tan, Jonathan Charles; Chatterjee, Sourav; Hu, Xiao; Zhu, Zhaohuan; Mohanty, Subhanjoy

    2015-08-01

    The Kepler-discovered systems with tightly-packed inner planets (STIPs), typically with several planets of Earth to super-Earth masses on well-aligned, sub-AU orbits may host the most common type of planets in the Galaxy. They pose a great challenge for planet formation theories, which fall into two broad classes: (1) formation further out followed by migration; (2) formation in situ from a disk of gas and planetesimals. I review the pros and cons of these classes, before focusing on a new theory of sequential in situ formation from the inside-out via creation of successive gravitationally unstable rings fed from a continuous stream of small (~cm-m size) "pebbles," drifting inward via gas drag. Pebbles first collect at the pressure trap associated with the transition from a magnetorotational instability (MRI)-inactive ("dead zone") region to an inner MRI-active zone. A pebble ring builds up until it either becomes gravitationally unstable to form an Earth to super-Earth-mass planet directly or induces gradual planet formation via core accretion. The planet continues to accrete until it becomes massive enough to isolate itself from the accretion flow via gap opening. The process repeats with a new pebble ring gathering at the new pressure maximum associated with the retreating dead-zone boundary. I discuss the theory’s predictions for planetary masses, relative mass scalings with orbital radius, and minimum orbital separations, and their comparison with observed systems. Finally I speculate about potential causes of diversity of planetary system architectures, i.e., STIPs versus Solar System analogs.

  11. Catastrophic evaporation of rocky planets

    NASA Astrophysics Data System (ADS)

    Perez-Becker, Daniel; Chiang, Eugene

    2013-08-01

    Short-period exoplanets can have dayside surface temperatures surpassing 2000 K, hot enough to vaporize rock and drive a thermal wind. Small enough planets evaporate completely. We construct a radiative hydrodynamic model of atmospheric escape from strongly irradiated, low-mass rocky planets, accounting for dust-gas energy exchange in the wind. Rocky planets with masses ≲ 0.1 M⊕ (less than twice the mass of Mercury) and surface temperatures ≳2000 K are found to disintegrate entirely in ≲10 Gyr. When our model is applied to Kepler planet candidate KIC 12557548b - which is believed to be a rocky body evaporating at a rate of dot{M} gtrsim 0.1 M_{{{oplus }}} Gyr-1 - our model yields a present-day planet mass of ≲ 0.02 M⊕ or less than about twice the mass of the Moon. Mass-loss rates depend so strongly on planet mass that bodies can reside on close-in orbits for Gyr with initial masses comparable to or less than that of Mercury, before entering a final short-lived phase of catastrophic mass-loss (which KIC 12557548b has entered). Because this catastrophic stage lasts only up to a few per cent of the planet's life, we estimate that for every object like KIC 12557548b, there should be 10-100 close-in quiescent progenitors with sub-day periods whose hard-surface transits may be detectable by Kepler - if the progenitors are as large as their maximal, Mercury-like sizes (alternatively, the progenitors could be smaller and more numerous). According to our calculations, KIC 12557548b may have lost ˜70 per cent of its formation mass; today we may be observing its naked iron core.

  12. LIGHT SCATTERING FROM EXOPLANET OCEANS AND ATMOSPHERES

    SciTech Connect

    Zugger, M. E.; Kane, T. J.; Kasting, J. F.; Williams, D. M.; Philbrick, C. R.

    2010-11-10

    Orbital variation in reflected starlight from exoplanets could eventually be used to detect surface oceans. Exoplanets with rough surfaces, or dominated by atmospheric Rayleigh scattering, should reach peak brightness in full phase, orbital longitude (OL) = 180{sup 0}, whereas ocean planets with transparent atmospheres should reach peak brightness in crescent phase near OL = 30{sup 0}. Application of Fresnel theory to a planet with no atmosphere covered by a calm ocean predicts a peak polarization fraction of 1 at OL = 74{sup 0}; however, our model shows that clouds, wind-driven waves, aerosols, absorption, and Rayleigh scattering in the atmosphere and within the water column dilute the polarization fraction and shift the peak to other OLs. Observing at longer wavelengths reduces the obfuscation of the water polarization signature by Rayleigh scattering but does not mitigate the other effects. Planets with thick Rayleigh scattering atmospheres reach peak polarization near OL = 90{sup 0}, but clouds and Lambertian surface scattering dilute and shift this peak to smaller OL. A shifted Rayleigh peak might be mistaken for a water signature unless data from multiple wavelength bands are available. Our calculations suggest that polarization alone may not positively identify the presence of an ocean under an Earth-like atmosphere; however, polarization adds another dimension which can be used, in combination with unpolarized orbital light curves and contrast ratios, to detect extrasolar oceans, atmospheric water aerosols, and water clouds. Additionally, the presence and direction of the polarization vector could be used to determine planet association with the star, and constrain orbit inclination.

  13. Bullying, Social Power and Heteronormativity: Girls' Constructions of Popularity

    ERIC Educational Resources Information Center

    Duncan, Neil; Owens, Larry

    2011-01-01

    Literature on girls' popularity posits a strong association between popularity, social power and bullying behaviours, some of which conflate the concepts "bully" and "popular". This study explores that association through links to concepts of popularity among girls in two demographically different high schools. Data are presented that were derived…

  14. Focus: Popular Culture, Censorship, Religion in the Schools.

    ERIC Educational Resources Information Center

    Stewart, Donald, Ed.

    1976-01-01

    This issue of "Kansas English" contains four articles related to popular culture, censorship, and religion. "Popular Culture Studies: A Complement to the Humanities" by Michael Marsden, focuses on the relationship between popular culture studies and the humanities, including English. "Popular Couture: La Vie En Blue" by Richard Martin, examines…

  15. Lights, Camera, Action: Integrating Popular Film in the Health Classroom

    ERIC Educational Resources Information Center

    Diez, Keri S.; Pleban, Francis T.; Wood, Ralph J.

    2005-01-01

    This article discusses the benefits as well as the important considerations that should be taken into account in integrating popular films in health education classes. Use of popular films in the classroom, termed "cinema education," is becoming increasingly popular in teaching health education. As a matter of convenience, popular films are easy…

  16. Lights, Camera, Action: Integrating Popular Film in the Health Classroom

    ERIC Educational Resources Information Center

    Diez, Keri S.; Pleban, Francis T.; Wood, Ralph J.

    2005-01-01

    This article discusses the benefits as well as the important considerations that should be taken into account in integrating popular films in health education classes. Use of popular films in the classroom, termed "cinema education," is becoming increasingly popular in teaching health education. As a matter of convenience, popular films are easy

  17. Bullying, Social Power and Heteronormativity: Girls' Constructions of Popularity

    ERIC Educational Resources Information Center

    Duncan, Neil; Owens, Larry

    2011-01-01

    Literature on girls' popularity posits a strong association between popularity, social power and bullying behaviours, some of which conflate the concepts "bully" and "popular". This study explores that association through links to concepts of popularity among girls in two demographically different high schools. Data are presented that were derived

  18. The Popularity of P&P

    ERIC Educational Resources Information Center

    Ruffins, Paul

    2006-01-01

    "Principles and Practices" (P&P), a real estate pre-licensing class, is one of the most popular courses in adult education, because it can literally be the key to the dual American dreams: striking it rich and owning a home. One of the things that makes the P&P class unique is that it is taught in so many different venues. The classes are often…

  19. Alcohol brand appearances in US popular music.

    TOXLINE Toxicology Bibliographic Information

    Primack BA; Nuzzo E; Rice KR; Sargent JD

    2012-03-01

    AIMS: The average US adolescent is exposed to 34 references to alcohol in popular music daily. Although brand recognition is an independent, potent risk factor for alcohol outcomes among adolescents, alcohol brand appearances in popular music have not been assessed systematically. We aimed to determine the prevalence of and contextual elements associated with alcohol brand appearances in US popular music.DESIGN: Qualitative content analysis.SETTING: We used Billboard Magazine to identify songs to which US adolescents were most exposed in 2005-07. For each of the 793 songs, two trained coders analyzed independently the lyrics of each song for references to alcohol and alcohol brand appearances. Subsequent in-depth assessments utilized Atlas.ti to determine contextual factors associated with each of the alcohol brand appearances.MEASUREMENTS: Our final code book contained 27 relevant codes representing six categories: alcohol types, consequences, emotional states, activities, status and objects.FINDINGS: Average inter-rater reliability was high (κ = 0.80), and all differences were easily adjudicated. Of the 793 songs in our sample, 169 (21.3%) referred explicitly to alcohol, and of those, 41 (24.3%) contained an alcohol brand appearance. Consequences associated with alcohol were more often positive than negative (41.5% versus 17.1%, P < 0.001). Alcohol brand appearances were associated commonly with wealth (63.4%), sex (58.5%), luxury objects (51.2%), partying (48.8%), other drugs (43.9%) and vehicles (39.0%).CONCLUSIONS: One in five songs sampled from US popular music had explicit references to alcohol, and one-quarter of these mentioned a specific alcohol brand. These alcohol brand appearances are associated commonly with a luxury life-style characterized by wealth, sex, partying and other drugs.

  20. Fourier spectra from exoplanets with polar caps and ocean glint

    NASA Astrophysics Data System (ADS)

    Visser, P. M.; van de Bult, F. J.

    2015-07-01

    Context. The weak orbital-phase dependent reflection signal of an exoplanet contains information on the planet surface, such as the distribution of continents and oceans on terrestrial planets. This light curve is usually studied in the time domain, but because the signal from a stationary surface is (quasi)periodic, analysis of the Fourier series may provide an alternative, complementary approach. Aims: We study Fourier spectra from reflected light curves for geometrically simple configurations. Depending on its atmospheric properties, a rotating planet in the habitable zone could have circular polar ice caps. Tidally locked planets, on the other hand, may have symmetric circular oceans facing the star. These cases are interesting because the high-albedo contrast at the sharp edges of the ice-sheets and the glint from the host star in the ocean may produce recognizable light curves with orbital periodicity, which could also be interpreted in the Fourier domain. Methods: We derive a simple general expression for the Fourier coefficients of a quasiperiodic light curve in terms of the albedo map of a Lambertian planet surface. Analytic expressions for light curves and their spectra are calculated for idealized situations, and dependence of the spectral peaks on the key parameters inclination, obliquity, and cap size is studied. Results: The ice-scattering and ocean glint contributions can be separated out, because the coefficients for glint are all positive, whereas ice sheets lead to even-numbered, higher harmonics. An in-view polar cap on a planet without axial tilt only produces a single peak. The special situation of edge-on observation, which is important for planets in transit, leads to the most pronounced spectral behavior. Then the respective spectra from planets with a circumventing ocean, a circular ocean (eyeball world), polar caps, and rings, have characteristic power-law tails n-2, n-7/2, n-4, and (-1)n + 1n-2. Conclusions: Promising recently discovered planetary systems may be selected as candidates for long-term (multiyear) observation: their Fourier spectra could separate the different planets and reveal or identify a water-covered planet with polar caps. Appendices are available in electronic form at http://www.aanda.org

  1. Cooperation and popularity in spatial games

    NASA Astrophysics Data System (ADS)

    Zhang, Hai-Feng; Jin, Zhen; Wang, Zhen

    2014-11-01

    Selection of the competition opponent is crucial for the evolution of cooperation in evolutionary games. In this work, we introduce a simple rule, incorporating individual popularity via the single parameter α, to study how the selection of the potential strategy sources influences individual behavior traits. For positive α players with high popularity will be considered more likely, while for negative α the opposite holds. Setting α equal to zero returns the frequently adopted random selection of the opponent. We find that positive α (namely, adopting the strategy from a more popular player) promotes the emergence of cooperation, which is robust against different interaction networks and game classes. The essence of this boosting effect can be attributed to the fact: increasing α accelerates the microscopic organization of cooperator clusters to resist the exploitation of defectors. Moreover, we also demonstrated that the introduction of a new mechanism alters the impact of uncertainty by strategy adoption on the evolution of cooperation. We thus present a viable method of understanding the ubiquitous cooperative behaviors in nature and hope that it will inspire further studies to resolve social dilemmas.

  2. Explanatory Framework for Popular Physics Lectures

    NASA Astrophysics Data System (ADS)

    Kapon, Shulamit; Ganiel, Uri; Eylon, Bat Sheva

    2007-11-01

    Popular physics lectures provide a `translation' that bridges the gap between the specialized knowledge that formal scientific content is based on, and the audience's informal prior knowledge. This paper presents an overview of a grounded theory explanatory framework for Translated Scientific Explanations (TSE) in such lectures, focusing on one of its aspects, the conceptual blending cluster. The framework is derived from a comparative study of three exemplary popular physics lectures from two perspectives: the explanations in the lecture (as artifacts), and the design of the explanation from the lecturer's point of view. The framework consists of four clusters of categories: 1. Conceptual blending (e.g. metaphor). 2. Story (e.g. narrative). 3. Content (e.g. selection of level). 4. Knowledge organization (e.g. structure). The framework shows how the lecturers customized the content of the presentation to the audience's knowledge. Lecture profiles based upon this framework can serve as guides for utilizing popular physics lectures when teaching contemporary physics to learners lacking the necessary science background. These features are demonstrated through the conceptual blending cluster.

  3. Reaching for the red planet

    PubMed

    David, L

    1996-05-01

    The distant shores of Mars were reached by numerous U.S. and Russian spacecraft throughout the 1960s to mid 1970s. Nearly 20 years have passed since those successful missions which orbited and landed on the Martian surface. Two Soviet probes headed for the planet in July, 1988, but later failed. In August 1993, the U.S. Mars Observer suddenly went silent just three days before it was to enter orbit around the planet and was never heard from again. In late 1996, there will be renewed activity on the launch pads with three probes departing for the red planet: 1) The U.S. Mars Global Surveyor will be launched in November on a Delta II rocket and will orbit the planet for global mapping purposes; 2) Russia's Mars '96 mission, scheduled to fly in November on a Proton launcher, consists of an orbiter, two small stations which will land on the Martian surface, and two penetrators that will plow into the terrain; and finally, 3) a U.S. Discovery-class spacecraft, the Mars Pathfinder, has a December launch date atop a Delta II booster. The mission features a lander and a microrover that will travel short distances over Martian territory. These missions usher in a new phase of Mars exploration, setting the stage for an unprecedented volley of spacecraft that will orbit around, land on, drive across, and perhaps fly at low altitudes over the planet. PMID:11538726

  4. Finding Materials on American Popular Culture in the MSU Libraries: Popular Music, Television, Comics, Popular Fiction, Movies. How to Find Series No. 9.

    ERIC Educational Resources Information Center

    Scott, Randall W., Comp.

    An introduction to popular culture materials in the Michigan State University Libraries, this combination library guide and bibliography presents finding tools for popular fiction, comic materials, popular music, movies, and television programming. It provides instruction on the use of the card catalog, suggested subject heading search terms, and

  5. Finding Materials on American Popular Culture in the MSU Libraries: Popular Music, Television, Comics, Popular Fiction, Movies. How to Find Series No. 9.

    ERIC Educational Resources Information Center

    Scott, Randall W., Comp.

    An introduction to popular culture materials in the Michigan State University Libraries, this combination library guide and bibliography presents finding tools for popular fiction, comic materials, popular music, movies, and television programming. It provides instruction on the use of the card catalog, suggested subject heading search terms, and…

  6. The differentiation history of the terrestrial planets as recorded on the moon

    SciTech Connect

    Borg, L

    2007-02-20

    The outline for this report is: (1) Factors Leading to Lunar Magma Ocean Model for Planetary Differentiation (2) Rationale for Magma Oceans on Other Planets Means for early efficient differentiation (Works on Moon why not here?) (3) Some Inconsistencies between the Lunar Magma Ocean Model and Observations. The conclusions are: (1) Differentiation via solidification of a magma ocean is derived from geologic observations of the Moon (2) Although geologic observations on other bodies are often consistent with differentiation via magma ocean solidification, it is not generally required. (3) There are some fundamental inconsistencies between observed lunar data and the model, that will require this model to be modified (4) Nevertheless, the Moon is the only location we know of to study magma ocean process in detail.

  7. The carbonate-silicate cycle and CO2/climate feedbacks on tidally locked terrestrial planets.

    PubMed

    Edson, Adam R; Kasting, James F; Pollard, David; Lee, Sukyoung; Bannon, Peter R

    2012-06-01

    Atmospheric gaseous constituents play an important role in determining the surface temperatures and habitability of a planet. Using a global climate model and a parameterization of the carbonate-silicate cycle, we explored the effect of the location of the substellar point on the atmospheric CO(2) concentration and temperatures of a tidally locked terrestrial planet, using the present Earth continental distribution as an example. We found that the substellar point's location relative to the continents is an important factor in determining weathering and the equilibrium atmospheric CO(2) level. Placing the substellar point over the Atlantic Ocean results in an atmospheric CO(2) concentration of 7 ppmv and a global mean surface air temperature of 247 K, making ∼30% of the planet's surface habitable, whereas placing it over the Pacific Ocean results in a CO(2) concentration of 60,311 ppmv and a global temperature of 282 K, making ∼55% of the surface habitable. PMID:22775488

  8. Habitable zone limits for dry planets.

    PubMed

    Abe, Yutaka; Abe-Ouchi, Ayako; Sleep, Norman H; Zahnle, Kevin J

    2011-06-01

    Most discussion of habitable planets has focused on Earth-like planets with globally abundant liquid water. For an "aqua planet" like Earth, the surface freezes if far from its sun, and the water vapor greenhouse effect runs away if too close. Here we show that "land planets" (desert worlds with limited surface water) have wider habitable zones than aqua planets. For planets at the inner edge of the habitable zone, a land planet has two advantages over an aqua planet: (i) the tropics can emit longwave radiation at rates above the traditional runaway limit because the air is unsaturated and (ii) the dry air creates a dry stratosphere that limits hydrogen escape. At the outer limits of the habitable zone, the land planet better resists global freezing because there is less water for clouds, snow, and ice. Here we describe a series of numerical experiments using a simple three-dimensional global climate model for Earth-sized planets. Other things (CO(2), rotation rate, surface pressure) unchanged, we found that liquid water remains stable at the poles of a low-obliquity land planet until net insolation exceeds 415 W/m(2) (170% that of modern Earth), compared to 330 W/m(2) (135%) for the aqua planet. At the outer limits, we found that a low-obliquity land planet freezes at 77%, while the aqua planet freezes at 90%. High-obliquity land and aqua planets freeze at 58% and 72%, respectively, with the poles offering the last refuge. We show that it is possible that, as the Sun brightens, an aqua planet like Earth can lose most of its hydrogen and become a land planet without first passing through a sterilizing runaway greenhouse. It is possible that Venus was a habitable land planet as recently as 1 billion years ago. PMID:21707386

  9. Mercury - the hollow planet

    NASA Astrophysics Data System (ADS)

    Rothery, D. A.

    2012-04-01

    Mercury is turning out to be a planet characterized by various kinds of endogenous hole (discounting impact craters), which are compared here. These include volcanic vents and collapse features on horizontal scales of tens of km, and smaller scale depressions ('hollows') associated with bright crater-floor deposits (BCFD). The BCFD hollows are tens of metres deep and kilometres or less across and are characteristically flat-floored, with steep, scalloped walls. Their form suggests that they most likely result from removal of surface material by some kind of mass-wasting process, probably associated with volume-loss caused by removal (via sublimation?) of a volatile component. These do not appear to be primarily a result of undermining. Determining the composition of the high-albedo bluish surface coating in BCFDs will be a key goal for BepiColombo instruments such as MIXS (Mercury Imaging Xray Spectrometer). In contrast, collapse features are non-circular rimless pits, typically on crater floors (pit-floor craters), whose morphology suggests collapse into void spaces left by magma withdrawal. This could be by drainage of either erupted lava (or impact melt) or of shallowly-intruded magma. Unlike the much smaller-scale BCFD hollows, these 'collapse pit' features tend to lack extensive flat floors and instead tend to be close to triangular in cross-section with inward slopes near to the critical angle of repose. The different scale and morphology of BCFD hollows and collapse pits argues for quite different modes of origin. However, BCFD hollows adjacent to and within the collapse pit inside Scarlatti crater suggest that the volatile material whose loss was responsible for the growth of the hollows may have been emplaced in association with the magma whose drainage caused the main collapse. Another kind of volcanic collapse can be seen within a 25 km-wide volcanic vent outside the southern rim of the Caloris basin (22.5° N, 146.1° E), on a 28 m/pixel MDIS NAC image from orbit. Although the vent itself may have been excavated partly by explosive volcanism, the most recent event is collapse of a 7 km wide zone in the south centre of the vent. The sharpness of features within this (unmuted either by regolith-forming processes or by fall of volcanic ejecta) suggests that this collapse considerably post-dates the rest of the vent interior. It could reflect a late-stage minor 'throat clearing' explosive eruption, but (in the absence of evidence of associated volcanic ejecta) more likely reflects collapse into a void within the volcanic conduit, itself a result of magma-drainage. A class of 'hole' that is so far conspicuous by its absence on Mercury is sinuous rilles (as opposed to much straighter tectonic grabens) or aligned skylights representing collapsed or partly-collapsed drained lava tubes. Tube-fed flows are to be expected during emplacement of volcanic plains, and it will be surprising if no examples are revealed on MESSENGER and BepiColombo high-resolution images.

  10. Characterizing K2 Planet Discoveries

    NASA Astrophysics Data System (ADS)

    Vanderburg, Andrew; Montet, Benjamin; Johnson, John; Buchhave, Lars A.; Zeng, Li; Bieryla, Allyson; Latham, David W.; Charbonneau, David; Harps-N Collaboration, The Robo-Ao Team

    2015-01-01

    We present an effort to confirm the first planet discovered by the two-wheeled Kepler mission. We analyzed K2 photometry, correcting for nonuniform detector response as a function of the spacecraft's pointing, and detected a transiting planet candidate. We describe our multi-telescope followup observing campaign, consisting of photometric, spectroscopic, and high resolution imaging observations, including over 40 HARPS-N radial velocity measurements. The new planet is a super-Earth orbiting a bright star amenable to followup observations. HARPS-N was funded by the Swiss Space Office, the Harvard Origin of Life Initiative, the Scottish Universities Physics Alliance, the University of Geneva, the Smithsonian Astrophysical Observatory, the Italian National Astrophysical Institute, the University of St. Andrews, Queens University Belfast, and the University of Edinburgh.

  11. Planet Masses from Disk Spirals

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-12-01

    Young, forming planets can generate immense spiral structures within their protoplanetary disks. A recent study has shown that observations of these spiral structures may allow astronomers to measure the mass of the planets that create them.Spirals From WavesSnapshots of the surface density of a protoplanetary disk in a 2D simulation, 3D simulation, and synthesized scattered-light image. Click for a closer look! [Fung Dong, 2015]Recent studies have shown that a single planet, if it is massive enough, can excite multiple density waves within a protoplanetary disk as it orbits. These density waves can then interfere to produce a multiple-armed spiral structure in the disk inside of the planets orbit a structure which can potentially be observed in scattered-light images of the disk.But what do these arms look like, and what factors determine their structure? In a recently published study, Jeffrey Fung and Ruobing Dong, two researchers at the University of California at Berkeley, have modeled the spiral arms in an effort to answer these questions.Arms Provide AnswersA useful parameter for describing the structure is the azimuthal separation (sep) between the primary and secondary spiral arms. If you draw a circle within the disk and measure the angle between the two points where the primary and secondary arms cross it, thats sep.Azimuthal separation of the primary and secondary spiral arms, as a function of the planet-to-star mass ratio q. The different curves represent different disk aspect ratios. [Fung Dong, 2015]The authors find thatsep stays roughly constant for different radii, but its strongly dependent on the planets mass: for larger planets, sep increases. They discover that sep scales as a power of the planet mass for companions between Neptune mass and 16 Jupiter masses, orbiting around a solar-mass star. For larger, brown-dwarf-size companions, sep is a constant 180.If this new theory is confirmed, it could have very interesting implications for observations of protoplanetary disks: this would give us the ability to measure the mass of a planet in a disk without ever needing to directly observe the planet itself!Modeling ObservationsFung and Dong confirm their models by additionally running 3D simulations, which yield very similar outcomes. From these simulation results, they then synthesize scattered-light images similar to what we would expect to be able to observe with telescopes like the VLT, Gemini, or Subaru. The authors demonstrate that from these scattered-light images, they can correctly retrieve the planets mass to within 30%.Finally, as a proof-of-concept, the authors apply this modeling to an actual system: SAO 206462, a nearly face-on protoplanetary disk with an observed two-armed spiral within it. From the measured azimuthal separation of the two arms, the authors estimate that it contains a planet of about 6 Jupiter masses.CitationJeffrey Fung () and Ruobing Dong () 2015 ApJ 815 L21. doi:10.1088/2041-8205/815/2/L21

  12. AN ULTRACOOL STAR'S CANDIDATE PLANET

    SciTech Connect

    Pravdo, Steven H.; Shaklan, Stuart B. E-mail: stuart.shaklan@jpl.nasa.gov

    2009-07-20

    We report here the discovery of the first planet around an ultracool dwarf star. It is also the first extrasolar giant planet astrometrically discovered around a main-sequence star. The statistical significance of the detection is shown in two ways. First, there is a 2 x 10{sup -8} probability that the astrometric motion fits a parallax-and-proper-motion-only model. Second, periodogram analysis shows a false alarm probability of 3 x 10{sup -5} that the discovered period is randomly generated. The planetary mass is M {sub 2} = 6.4 (+2.6,-3.1) Jupiter-masses (M {sub J}), and the orbital period is P = 0.744 (+0.013,-0.008) yr in the most likely model. In less likely models, companion masses that are higher than the 13 M {sub J} planetary mass limit are ruled out by past radial velocity (RV) measurements unless the system RV is more than twice the current upper limits and the near-periastron orbital phase was never observed. This new planetary system is remarkable, in part, because its star, VB 10, is near the lower mass limit for a star. Our astrometric observations provide a dynamical mass measurement and will in time allow us to confront the theoretical models of formation and evolution of such systems and their members. We thus add to the diversity of planetary systems and to the small number of known M-dwarf planets. Planets such as VB 10b could be the most numerous type of planets because M stars comprise >70% of all stars. To date they have remained hidden since the dominant RV planet-discovery technique is relatively insensitive to these dim, red systems.

  13. Habitable planets with high obliquities.

    PubMed

    Williams, D M; Kasting, J F

    1997-01-01

    Earth's obliquity would vary chaotically from 0 degrees to 85 degrees were it not for the presence of the Moon (J. Laskar, F. Joutel, and P. Robutel, 1993, Nature 361, 615-617). The Moon itself is thought to be an accident of accretion, formed by a glancing blow from a Mars-sized planetesimal. Hence, planets with similar moons and stable obliquities may be extremely rare. This has lead Laskar and colleagues to suggest that the number of Earth-like planets with high obliquities and temperate, life-supporting climates may be small. To test this proposition, we have used an energy-balance climate model to simulate Earth's climate at obliquities up to 90 degrees. We show that Earth's climate would become regionally severe in such circumstances, with large seasonal cycles and accompanying temperature extremes on middle- and high-latitude continents which might be damaging to many forms of life. The response of other, hypothetical, Earth-like planets to large obliquity fluctuations depends on their land-sea distribution and on their position within the habitable zone (HZ) around their star. Planets with several modest-sized continents or equatorial supercontinents are more climatically stable than those with polar supercontinents. Planets farther out in the HZ are less affected by high obliquities because their atmospheres should accumulate CO2 in response to the carbonate-silicate cycle. Dense, CO2-rich atmospheres transport heat very effectively and therefore limit the magnitude of both seasonal cycles and latitudinal temperature gradients. We conclude that a significant fraction of extrasolar Earth-like planets may still be habitable, even if they are subject to large obliquity fluctuations. PMID:11541242

  14. Habitable planets with high obliquities

    NASA Technical Reports Server (NTRS)

    Williams, D. M.; Kasting, J. F.

    1997-01-01

    Earth's obliquity would vary chaotically from 0 degrees to 85 degrees were it not for the presence of the Moon (J. Laskar, F. Joutel, and P. Robutel, 1993, Nature 361, 615-617). The Moon itself is thought to be an accident of accretion, formed by a glancing blow from a Mars-sized planetesimal. Hence, planets with similar moons and stable obliquities may be extremely rare. This has lead Laskar and colleagues to suggest that the number of Earth-like planets with high obliquities and temperate, life-supporting climates may be small. To test this proposition, we have used an energy-balance climate model to simulate Earth's climate at obliquities up to 90 degrees. We show that Earth's climate would become regionally severe in such circumstances, with large seasonal cycles and accompanying temperature extremes on middle- and high-latitude continents which might be damaging to many forms of life. The response of other, hypothetical, Earth-like planets to large obliquity fluctuations depends on their land-sea distribution and on their position within the habitable zone (HZ) around their star. Planets with several modest-sized continents or equatorial supercontinents are more climatically stable than those with polar supercontinents. Planets farther out in the HZ are less affected by high obliquities because their atmospheres should accumulate CO2 in response to the carbonate-silicate cycle. Dense, CO2-rich atmospheres transport heat very effectively and therefore limit the magnitude of both seasonal cycles and latitudinal temperature gradients. We conclude that a significant fraction of extrasolar Earth-like planets may still be habitable, even if they are subject to large obliquity fluctuations.

  15. Arctic Ocean

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)

    2000-01-01

    The Arctic Ocean is the smallest of the Earth's four major oceans, covering 14x10(exp 6) sq km located entirely within the Arctic Circle (66 deg 33 min N). It is a major player in the climate of the north polar region and has a variable sea ice cover that tends to increase its sensitivity to climate change. Its temperature, salinity, and ice cover have all undergone changes in the past several decades, although it is uncertain whether these predominantly reflect long-term trends, oscillations within the system, or natural variability. Major changes include a warming and expansion of the Atlantic layer, at depths of 200-900 m, a warming of the upper ocean in the Beaufort Sea, a considerable thinning (perhaps as high as 40%) of the sea ice cover, a lesser and uneven retreat of the ice cover (averaging approximately 3% per decade), and a mixed pattern of salinity increases and decreases.

  16. Ocean Spray

    NASA Astrophysics Data System (ADS)

    Veron, Fabrice

    2015-01-01

    Ocean spray consists of small water droplets ejected from the ocean surface following surface breaking wave events. These drops get transported in the marine atmospheric boundary layer, in which they exchange momentum and heat with the atmosphere. Small spray droplets are transported over large distances and can remain in the atmosphere for several days, where they will scatter radiation; evaporate entirely, leaving behind sea salt; participate in the aerosol chemical cycle; and act as cloud condensation nuclei. Large droplets remain close to the ocean surface and affect the air-sea fluxes of momentum and enthalpy, thereby enhancing the intensity of tropical cyclones. This review summarizes recent progress and the emerging consensus about the number flux and implications of small sea spray droplets. I also summarize shortcomings in our understanding of the impact of large spray droplets on the meteorology of storm systems.

  17. Recent Kepler Results On Circumbinary Planets

    NASA Astrophysics Data System (ADS)

    Welsh, William F.; Orosz, Jerome A.; Carter, Joshua A.; Fabrycky, Daniel C.

    2014-04-01

    Ranked near the top of the long list of exciting discoveries made with NASA's Kepler photometer is the detection of transiting circumbinary planets. In just over a year the number of such planets went from zero to seven, including a multi-planet system with one of the planets in the habitable zone (Kepler-47). We are quickly learning to better detect and characterize these planets, including the recognition of their transit timing and duration variation ``smoking gun'' signature. Even with only a handful of such planets, some exciting trends are emerging.

  18. Water Cycling Between Ocean and Mantle: Super-Earths Need Not be Waterworlds

    NASA Astrophysics Data System (ADS)

    Cowan, Nicolas B.; Abbot, D. S.

    2014-01-01

    Large terrestrial planets are expected to have muted topography and deep oceans, implying they should be entirely covered in water, so-called waterworlds. Quantitatively, a planet ten times the mass of Earth is not expected to have exposed continents unless it has a water mass fraction less than 3×10-5, roughly ten times drier than Earth. This is important because waterworlds lack a silicate weathering thermostat so their climate is predicted to be less stable than that of planets with exposed continents. Water is partitioned, however, between a surface reservoir, the ocean, and an interior reservoir, the mantle. Plate tectonics transports water between these reservoirs on geological timescales. Degassing of melt at mid-ocean ridges and serpentinization of oceanic crust are mediated by sea-floor pressure, providing a stabilizing feedback on long-term ocean volume. Motivated by Earth's approximately steady-state deep water cycle, we develop a two-box model of the hydrosphere and derive steady-state solutions to the water-partitioning on terrestrial planets. Since hydrostatic pressure is proportional to gravity, super-Earths with a deep water cycle will tend to store most of their water in the mantle. We conclude that tectonically active terrestrial planets with H2O mass fractions less than 3×10-3 will have both oceans and exposed continents. The circumstellar habitable zone is therefore equally wide for any tectonically active planet.

  19. The Sun, stars and planets (Christiaan Huygens Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Bertaux, Jean-Loup

    2010-05-01

    Using stellar occultations as a tool to probe the planetary atmospheres has resulted in significant contributions to the exploration of our solar system. The technique of solar occultation has been well known for decades, but because of stars being so faint objects with respect to the Sun this technique was not very popular in the 70's. While fostering the idea of stellar occultations, I tried to avoid the unfortunate fate of Giordano Bruno, who was burned to death on February 17, 1600: he had dared to declare that the stars were objects like the sun, only much more remote. This talk will illustrate some results obtained by the star occultation technique by one scientific example on each of the three planets which are equipped with a stellar occultation instrument: GOMOS on ENVISAT (ozone monitoring), SPICAM on board Mars Express (temperature profiles), and SPICAV on Venus Express (SO2). I will also talk about Cristiaan Huygens, the first to discuss (according to the historical review of Pierre Connes) the problem of extra-solar planets in modern scientific terms which are still valid to day. Finally, I will address the threat to the planet Earth posed by Mankind, with some discussions about demography and geo-engineering.

  20. The Solar Twin Planet Search

    NASA Astrophysics Data System (ADS)

    Bedell, Megan; Bean, J.; Melendez, J.; Monroe, T.

    2014-01-01

    We present preliminary results from an ongoing radial velocity planet search around solar twins using the HARPS spectrograph. By limiting our sample to stars with Teff +/- 100 K, log(g) +/- 0.1 dex, and [Fe/H] +/- 0.1 dex of the solar values, we can obtain stellar elemental abundances [X/Fe] to a precision of 0.01 dex (Melendez et al. 2009). Our study is leveraging this unprecedented level of precision and the sensitivity of the HARPS instrument to investigate the connection between planet occurrence and stellar abundances at a new level of detail.

  1. Chemical kinetics on extrasolar planets.

    PubMed

    Moses, Julianne I

    2014-04-28

    Chemical kinetics plays an important role in controlling the atmospheric composition of all planetary atmospheres, including those of extrasolar planets. For the hottest exoplanets, the composition can closely follow thermochemical-equilibrium predictions, at least in the visible and infrared photosphere at dayside (eclipse) conditions. However, for atmospheric temperatures approximately <2000K, and in the uppermost atmosphere at any temperature, chemical kinetics matters. The two key mechanisms by which kinetic processes drive an exoplanet atmosphere out of equilibrium are photochemistry and transport-induced quenching. I review these disequilibrium processes in detail, discuss observational consequences and examine some of the current evidence for kinetic processes on extrasolar planets. PMID:24664912

  2. Hubble Observes the Planet Uranus

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This NASA Hubble Space Telescope image of the planet Uranus reveals the planet's rings and bright clouds and a high altitude haze above the planet's south pole.

    Hubble's new view was obtained on August 14, 1994, when Uranus was 1.7 billion miles (2.8 billion kilometers) from Earth. These details, as imaged by the Wide Field Planetary Camera 2, were only previously seen by the Voyager 2 spacecraft, which flew by Uranus in 1986. Since then, none of these inner satellites has been further observed, and detailed observations of the rings have not been possible.

    Though Uranus' rings were discovered indirectly in 1977 (through stellar occultation observations), they have never before been seen in visible light through a ground-based telescope.

    Hubble resolves several of Uranus' rings, including the outermost Epsilon ring. The planet has a total of 11 concentric rings of dark dust. Uranus is tipped such that its rotation axis lies in the plane of its orbit, so the rings appear nearly face-on.

    Three of Uranus' inner moons each appear as a string of three dots at the bottom of the picture. This is because the picture is a composite of three images, taken about six minutes apart, and then combined to show the moons' orbital motions. The satellites are, from left to right, Cressida, Juliet, and Portia. The moons move much more rapidly than our own Moon does as it moves around the Earth, so they noticeably change position over only a few minutes.

    One of the four gas giant planets of our solar system, Uranus is largely featureless. HST does resolve a high altitude haze which appears as a bright 'cap' above the planet's south pole, along with clouds at southern latitudes (similar structures were observed by Voyager). Unlike Earth, Uranus' south pole points toward the Sun during part of the planet's 84-year orbit. Thanks to its high resolution and ability to make observations over many years, Hubble can follow seasonal changes in Uranus's atmosphere, which should be unusual given the planet's large tilt.

    The Wide Field/Planetary Camera 2 was developed by the Jet Propulsion Laboratory and managed by the Goddard Spaced Flight Center for NASA's Office of Space Science.

    This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  3. HUBBLE OBSERVES THE PLANET URANUS

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This NASA Hubble Space Telescope image of the planet Uranus reveals the planet's rings and bright clouds and a high altitude haze above the planet's south pole. Hubble's new view was obtained on August 14, 1994, when Uranus was 1.7 billion miles (2.8 billion kilometers) from Earth. These details, as imaged by the Wide Field Planetary Camera 2, were only previously seen by the Voyager 2 spacecraft, which flew by Uranus in 1986. Since then, none of these inner satellites has been further observed, and detailed observations of the rings have not been possible. Though Uranus' rings were discovered indirectly in 1977 (through stellar occultation observations), they have never before been seen in visible light through a ground-based telescope. Hubble resolves several of Uranus' rings, including the outermost Epsilon ring. The planet has a total of 11 concentric rings of dark dust. Uranus is tipped such that its rotation axis lies in the plane of its orbit, so the rings appear nearly face-on. Three of Uranus' inner moons each appear as a string of three dots at the bottom of the picture. This is because the picture is a composite of three images, taken about six minutes apart, and then combined to show the moons' orbital motions. The satellites are, from left to right, Cressida, Juliet, and Portia. The moons move much more rapidly than our own Moon does as it moves around the Earth, so they noticeably change position over only a few minutes. One of the four gas giant planets of our solar system, Uranus is largely featureless. HST does resolve a high altitude haze which appears as a bright 'cap' above the planet's south pole, along with clouds at southern latitudes (similar structures were observed by Voyager). Unlike Earth, Uranus' south pole points toward the Sun during part of the planet's 84-year orbit. Thanks to its high resolution and ability to make observations over many years, Hubble can follow seasonal changes in Uranus's atmosphere, which should be unusual given the planet's large tilt. Credit: Kenneth Seidelmann, U.S. Naval Observatory, and NASA These observations were conducted by a team led by Dr. Ken Seidelmann of the U.S. Naval Observatory as Principal Investigator. These images have been processed by Professor Douglas Currie and Mr. Dan Dowling in the Department of Physics at the University of Maryland. Other team members are Dr. Ben Zellner at Georgia Southern University, Dr. Dan Pascu and Mr. Jim Rhode at the U.S. Naval Observatory, and Dr. Ed Wells, Mr. Charles Kowal (Computer Science Corporation) and Dr. Alex Storrs of the Space Telescope Science Institute.

  4. Wide Giant Planets are Rare: Planet Demographics from Direct Imaging

    NASA Astrophysics Data System (ADS)

    Biller, Beth

    2015-08-01

    The previous generation of direct imaging surveys probed samples of 100-200 stars with AO-driven coronagraphic imaging and advanced techniques such as Angular Differential Imaging (ADI) (e.g. surveys such as SEEDS, IDPS, the NICI Science Campaign, among others). These surveys found that wide giant planets are comparatively rare, especially at separations > 50 AU: for instance, Biller et al. 2013 find for a sample of 78 young moving group stars that the the frequency of 1-20 M Jup companions at semi-major axes from 10-150 AU is <18% at a 95.4% confidence level using DUSTY models and <6% at a 95.4% using COND models. As next generation planet-finding cameras such as GPI at Gemini, SPHERE at VLT, project 1640, and SceXAO at Suburu come online, our understanding of wide planet populations is likely to undergo a rapid evolution, especially for planets at separations of 10-50 AU. New large-scale surveys (400-500 stars) are now underway with these new instruments, e.g. NIRSUR with SPHERE and GPIES with GPI. In this talk, I will review the previous generation of surveys and the statistical results that they have yielded. I will also discuss prospects for the new generation of ongoing surveys.

  5. Workshop on Oxygen in the Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This volume contains abstracts that have been accepted for presentation at the Workshop on Oxygen in the Terrestrial Planets, July 20-23,2004, Santa Fe, New Mexico. The contents include: 1) Experimental Constraints on Oxygen and Other Light Element Partitioning During Planetary Core Formation; 2) In Situ Determination of Fe(3+)/SigmaFe of Spinels by Electron Microprobe: An Evaluation of the Flank Method; 3) The Effect of Oxygen Fugacity on Large-Strain Deformation and Recrystallization of Olivine; 4) Plagioclase-Liquid Trace Element Oxygen Barometry and Oxygen Behaviour in Closed and Open System Magmatic Processes; 5) Core Formation in the Earth: Constraints from Ni and Co; 6) Oxygen Isotopic Compositions of the Terrestrial Planets; 7) The Effect of Oxygen Fugacity on Electrical Conduction of Olivine and Implications for Earth s Mantle; 8) Redox Chemical Diffusion in Silicate Melts: The Impact of the Semiconductor Condition; 9) Ultra-High Temperature Effects in Earth s Magma Ocean: Pt and W Partitioning; 10) Terrestrial Oxygen and Hydrogen Isotope Variations: Primordial Values, Systematics, Subsolidus Effects, Planetary Comparisons, and the Role of Water; 11) Redox State of the Moon s Interior; 12) How did the Terrestrial Planets Acquire Their Water?; 13) Molecular Oxygen Mixing Ratio and Its Seasonal Variability in the Martian Atmosphere; 14) Exchange Between the Atmosphere and the Regolith of Mars: Discussion of Oxygen and Sulfur Isotope Evidence; 15) Oxygen and Hydrogen Isotope Systematics of Atmospheric Water Vapor and Meteoric Waters: Evidence from North Texas; 16) Implications of Isotopic and Redox Heterogeneities in Silicate Reservoirs on Mars; 17) Oxygen Isotopic Variation of the Terrestrial Planets; 18) Redox Exchanges in Hydrous Magma; 19) Hydrothermal Systems on Terrestrial Planets: Lessons from Earth; 20) Oxygen in Martian Meteorites: A Review of Results from Mineral Equilibria Oxybarometers; 21) Non-Linear Fractionation of Oxygen Isotopes Implanted in Lunar Metal Grains: Solar, Lunar or Terrestrial Origin? 22) Isotopic Zoning in the Inner Solar System; 23) Redox Conditions on Small Bodies; 24) Determining the Oxygen Fugacity of Lunar Pyroclastic Glasses Using Vanadium Valence - An Update; 25) Mantle Redox Evolution and the Rise of Atmospheric O2; 26) Variation of Kd for Fe-Mg Exchange Between Olivine and Melt for Compositions Ranging from Alkaline Basalt to Rhyolite; 27) Determining the Partial Pressure of Oxygen (PO,) in Solutions on Mars; 28) The Influence of Oxygen Environment on Kinetic Properties of Silicate Rocks and Minerals; 29) Redox Evolution of Magmatic Systems; 30) The Constancy of Upper Mantlefo, Through Time Inferred from V/Sc Ratios in Basalts: Implications for the Rise in Atmospheric 0 2; 31) Nitrogen Solubility in Basaltic Melt. Effects of Oxygen Fugacity, Melt Composition and Gas Speciation; 32) Oxygen Isotope Anomalies in the Atmospheres of Earth and Mars; 33) The Effect of Oxygen Fugacity on Interdiffusion of Iron and Magnesium in Magnesiowiistite 34) The Calibration of the Pyroxene Eu-Oxybarometer for the Martian Meteorites; 35) The Europium Oxybarometer: Power and Pitfalls; 36) Oxygen Fugacity of the Martian Mantle from PigeoniteMelt Partitioning of Samarium, Europium and Gadolinium; 37) Oxidation-Reduction Processes on the Moon: Experimental Verification of Graphite Oxidation in the Apollo 17 Orange Glasses; 38) Oxygen and Core Formation in the Earth; 39) Geologic Record of the Atmospheric Sulfur Chemistry Before the Oxygenation of the Early Earth s Atmosphere; 40) Comparative Planetary Mineralogy: V/(CrCAl) Systematics in Chromite as an Indicator of Relative Oxygen Fugacity; 41) How Well do Sulfur Isotopes Constrain Oxygen Abundance in the Ancient Atmospheres? 42) Experimental Constraints on the Oxygen Isotope (O-18/ O-16) Fractionation in the Ice vapor and Adsorbant vapor Systems of CO2 at Conditions Relevant to the Surface of Mars; 43) Micro-XANES Measurements on Experimental Spinels andhe Oxidation State of Vanadium in Spinel-Melt Pairs; 44) Testing the Magma Ocean Hypothesis Using Metal-Silicate Partitioning of Te, Se and S; 45) Solubility of Oxygen in Liquid Iron at High Pressure and Consequences for the Early Differentiation of Earth and Mars Metallic Liquid Segregation in Planetesimals; 46) Oxygen Fugacity of Lunar Basalts and the Lunar Mantle. Range of fo2 and the Effectiveness of Oxybarometers; 47) Thermodynamic Study of Dissociation Processes of Molecular Oxygen in Vapor over Oxide Compounds; 48) Oxygen Profile of a Thermo-Haliophilic Community in the Badwater Salt Flat; 49) Oxygen Barometry Using Synchrotron MicroXANES of Vanadium; 50) Mass-Independent Isotopic Fractionation of Sulfur from Sulfides in the Huronian Supergroup, Canada; 51) Mass Independent Isotopes and Applications to Planetary Atmospheres; 52) Electrical Conductivity, Oxygen Fugacity, and Mantle Materials; 53) Crustal Evolution and Maturation on Earth: Oxygen Isotope Evidence; 54) The Oxygen Isotope Composition of the Moon: Implications for Planet Formation; 55) Oxygen Isotope Composition of Eucrites and Implications for the Formation of Crust on the HED Parent Body; and 56) The Role of Water in Determining the Oxygen Isotopic Composition of Planets.

  6. Ocean circulation

    NASA Astrophysics Data System (ADS)

    Thompson, Andrew F.; Rahmstorf, Stefan

    The ocean moderates the Earth's climate due to its vast capacity to store and transport heat; the influence of the large-scale ocean circulation on changes in climate is considered in this chapter. The ocean experiences both buoyancy forcing (through heating/cooling and evaporation/precipitation) and wind forcing. Almost all ocean forcing occurs at the surface, but these changes are communicated throughout the entire depth of the ocean through the meridional overturning circulation (MOC). In a few localized regions, water become sufficiently dense to penetrate thousands of meters deep, where it spreads, providing a continuous source of deep dense water to the entire ocean. Dense water returns to the surface and thus closes the MOC, either through density modification due to diapycnal mixing or by upwelling along sloping isopycnals across the Southern Ocean. Determination of the relative contributions of these two processes in the MOC remains an active area of research. Observations obtained primarily from isotopic compositions in ocean sediments provide substantial evidence that the structure of the MOC has changed significantly in the past. Indeed, large and abrupt changes to the Earth's climate during the past 120,000 years can be linked to either a reorganization or a complete collapse of the MOC. Two of the more dramatic instances of abrupt change include Dansgaard-Oeschger events, abrupt warmings that could exceed 10°C over a period as short as a few decades, and Heinrich events, which are associated with massive freshwater fluxes due to rapid iceberg discharges into the North Atlantic. Numerical models of varying complexity that have captured these abrupt transitions all underscore that the MOC is a highly nonlinear system with feedback loops, multiple equilibria, and hysteresis effects. Prediction of future abrupt shifts in the MOC or "tipping points" remains uncertain. However, the inferred behavior of the MOC during glacial climates suggests that significant modifications to the present circulation are possible and that any change is likely to have a large effect on the Earth's climate.

  7. Wandering stars. About planets and exo-planets: an introductory notebook

    NASA Astrophysics Data System (ADS)

    Cole, George H. A.

    pt. I. Observations reveal gravity. 1. Early observations. 1.1. Stars and planets. 1.2. Interpretations of the observations. 1.3. Sun, moon and earth. 1.4. The shapes of the orbits. 1.5. Kepler's laws of planetary motion. 1.6. Galileo's law of inertia: Newton's laws of motion. 1.7. Newton's law of gravitation. 1.8. A passing encounter without capture. 2. A planet and a sun: the role of gravity. 2.1. Specification of an elliptic orbit. 2.2. Equal areas in equal times. 2.3. Consequences of an elliptical path: the inverse square force law. 2.4. The semi-major axis and the period of the orbit: the 3rd law. 2.5. Two immediate consequences. 2.6. The energy in an elliptic orbit. 2.7. Specifying the orbit from observations. 2.8. The different possible orbits -- 3. Several planets: the centre of mass. 3.1. More than one planet. 3.2. Jupiter, Mars and the asteroids. 3.3. The centre of mass: two masses. 3.4. Transfer orbits. 3.5. Tidal forces. 3.6. The Roche limit. 4. The general structure of a planet. 4.1. Several energies. 4.2. Packing atoms together. 4.3. The mass-radius relation. 4.4. Maximum size and mass. 4.5. Defining a planetary body. 4.6. Cosmic bodies. 4.7. Planets and satellites: planetary bodies. 5. Fluid flows and magnetism. 5.1. The fluid state. 5.2. The importance of time scales. 5.3. Specifying fluid behaviour. 5.4. Isothermal insulating fluids. 5.5. Thermal insulating fluid flows. 5.6. Natural convection: volcanic activities. 5.7. Boundary conditions. 5.8. Electrically conducting fluids. 5.9. Application to planetary magnetic fields -- pt. II. General features of the Solar System. 6. The larger members of the Solar System. 6.1. The sun. 6.2. The planets. 6.3. Satellites. 6.4. Planetary rings. 6.5. Angular momentum. 6.6. Magnetism and rotation. 7. Smaller members: asteroids, comets and meteorites. 7.1. Asteriods. 7.2. Comets and meteor showers. 7.3. Meteorites. 7.4. The Edgeworth-Kuiper belt. 7.5. The Oort cloud. 8. The material of the Solar System. 8.1. The solar/cosmic abundance of the elements. 8.2. The formation of molecules. 8.3. The compositions of terrestrial materials. 8.4. The moon. 8.5. Venus. 8.6. The material of the Solar System. 8.7. Material in orbit. 9. Finding the ages of rocks: geochronology. 9.1. Atoms and radioactive decay. 9.2. Nuclear reactions. 9.3. An elementary method for dating rocks. 9.4. The closure temperature. 9.5. Selecting a particular decay mode. 9.6. Dating using nuclear reactors. 10. Surfaces and interiors. 10.1. The surface figure. 10.2. The interior. 10.3. The near-surface interior region. 10.4. Free body oscillations. 10.5. Empirical equations of state. 10.6. Fluid bodies. 11. The solid earth. 11.1. General parameters. 11.2. The interior seismic structure. 11.3. An active structure. 11.4. Plates and plate tectonics. 11.5. The inner and outer cores. 11.6. A dynamic earth. 11.7. Comments on the atmosphere. 12. The planets: Mercury and Mars. 12.1. Rotation and temperature. 12.2. Surface details. 12.3. Internal structure of mercury. 12.4. The Mercury atmosphere. 12.5. The general topology of Mars. 12.6. Martian geology. 12.7. Thermal Mars. 12.8. The internal structure of Mars. 12.9. The atmosphere of Mars. 12.10. A tentative history of Mars. 13. Planet Venus. 13.1. First views of the surface. 13.2. Surface details. 13.3. The Venus interior. 13.4. Venus atmosphere. 14. The planets: Jupiter and Saturn. 14.1. Surface features. 14.2. The heat budgets. 14.3. Visible surface compositions. 14.4. General comments on internal conditions. 14.5. Detailed model interiors. 14.6. Comment on interior heat flow. 14.7. Intrinsic magnetic fields. 15. The planets: Uranus and Neptune. 15.1. Surface features. 15.2. Heat budgets. 15.3. Visible surface compositions. 15.4. Internal structure and conditions. 15.5. Comment on interior heat flow. 15.6. Intrinsic magnetism. 16. Satellites of the Solar System. 16.1. The moon. 16.2. The satellites of Mars. 16.3. The larger satellites. 16.4. The smaller satellites. 16.5. Internal conditions: internal differentiation -- pt. III. Magnetism with the Solar System. 17. Intrinsic magnetism of the earth. 17.1. The magnetic poles. 17.2. The magnetic elements. 17.3. Separation into a dipole and non-dipole fields. 17.4. Short time variations: the secular variation. 17.5. Long time variations: magnetic field reversals. 17.6. The geomagnetic poles have moved: continental drift. 17.7. Creation of ocean floor. 18. The earth's external magnetism. 18.1. The effects of the solar emissions. 18.2. The interplanetary magnetic field. 18.3. The polar aurorae. 18.4. Magnetic storms and transient disturbances. 18.5. The special effect of the moon. 18.6. van Allen radiation belts. 19. The magnetism of the other planets. 19.1. The intrinsic magnetic fields. 19.2. The magnetosp

  8. 76 FR 26254 - NOAA's Office of Ocean Exploration and Research (OER) Strategic Plan FY 2011-FY 2015

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-06

    ... ocean role in the life and health of our planet, and will result in improved societal understanding and... order to assess changes in biodiversity, marine life and other natural resources or habitats... ocean data in new ways to describe the ocean's marine life and features, living and non-living...

  9. Astronomers Find First Earth-like Planet in Habitable Zone

    NASA Astrophysics Data System (ADS)

    2007-04-01

    Astronomers have discovered the most Earth-like planet outside our Solar System to date, an exoplanet with a radius only 50% larger than the Earth and capable of having liquid water. Using the ESO 3.6-m telescope, a team of Swiss, French and Portuguese scientists discovered a super-Earth about 5 times the mass of the Earth that orbits a red dwarf, already known to harbour a Neptune-mass planet. The astronomers have also strong evidence for the presence of a third planet with a mass about 8 Earth masses. ESO PR Photo 22a/07 ESO PR Photo 22a/07 The Planetary System Around Gliese 581 This exoplanet - as astronomers call planets around a star other than the Sun - is the smallest ever found up to now [1] and it completes a full orbit in 13 days. It is 14 times closer to its star than the Earth is from the Sun. However, given that its host star, the red dwarf Gliese 581 [2], is smaller and colder than the Sun - and thus less luminous - the planet nevertheless lies in the habitable zone, the region around a star where water could be liquid! The planet's name is Gliese 581 c. "We have estimated that the mean temperature of this super-Earth lies between 0 and 40 degrees Celsius, and water would thus be liquid," explains Stéphane Udry, from the Geneva Observatory (Switzerland) and lead-author of the paper reporting the result. "Moreover, its radius should be only 1.5 times the Earth's radius, and models predict that the planet should be either rocky - like our Earth - or fully covered with oceans," he adds. ESO PR Photo 22c/07 ESO PR Photo 22c/07 The star Gliese 581 "Liquid water is critical to life as we know it," avows Xavier Delfosse, a member of the team from Grenoble University (France). "Because of its temperature and relative proximity, this planet will most probably be a very important target of the future space missions dedicated to the search for extra-terrestrial life. On the treasure map of the Universe, one would be tempted to mark this planet with an X." The host star, Gliese 581, is among the 100 closest stars to us, located only 20.5 light-years away in the constellation Libra ("the Scales"). It has a mass of only one third the mass of the Sun. Such red dwarfs are intrinsically at least 50 times fainter than the Sun and are the most common stars in our Galaxy: among the 100 closest stars to the Sun, 80 belong to this class. "Red dwarfs are ideal targets for the search for low-mass planets where water could be liquid. Because such dwarfs emit less light, the habitable zone is much closer to them than it is around the Sun," emphasizes Xavier Bonfils, a co-worker from Lisbon University. Planets lying in this zone are then more easily detected with the radial-velocity method [3], the most successful in detecting exoplanets. ESO PR Photo 22d/07 ESO PR Photo 22d/07 Velocity Variations of Gl 581 Two years ago, the same team of astronomers already found a planet around Gliese 581 (see ESO 30/05). With a mass of 15 Earth-masses, i.e. similar to that of Neptune, it orbits its host star in 5.4 days. At the time, the astronomers had already seen hints of another planet. They therefore obtained a new set of measurements and found the new super-Earth, but also clear indications for another one, an 8 Earth-mass planet completing an orbit in 84 days. The planetary system surrounding Gliese 581 contains thus no fewer than 3 planets of 15 Earth masses or less, and as such is a quite remarkable system. The discovery was made thanks to HARPS (High Accuracy Radial Velocity for Planetary Searcher), perhaps the most precise spectrograph in the world. Located on the ESO 3.6-m telescope at La Silla, Chile, HARPS is able to measure velocities with a precision better than one metre per second (or 3.6 km/h)! HARPS is one of the most successful instruments for detecting exoplanets and holds already several recent records, including the discovery of another 'Trio of Neptunes' (ESO 18/06, see also ESO 22/04). ESO PR Video 22/07 ESO PR Video 22/07 Watch the video! The detected velocity variations are between 2 and 3 metres per second, corresponding to about 9 km/h! That's the speed of a person walking briskly. Such tiny signals could not have been distinguished from 'simple noise' by most of today's available spectrographs. "HARPS is a unique planet hunting machine," says Michel Mayor, from Geneva Observatory, and HARPS Principal Investigator. "Given the incredible precision of HARPS, we have focused our effort on low-mass planets. And we can say without doubt that HARPS has been very successful: out of the 13 known planets with a mass below 20 Earth masses, 11 were discovered with HARPS!" HARPS is also very efficient in finding planetary systems, where tiny signals have to be uncovered. The two systems known to have three low mass planets - HD 69830 and Gl 581 - were discovered by HARPS. "And we are confident that, given the results obtained so far, finding a planet with the mass of the Earth around a red dwarf is within reach," affirms Mayor.

  10. A window for plate tectonics in terrestrial planet evolution?

    NASA Astrophysics Data System (ADS)

    O'Neill, Craig; Lenardic, Adrian; Weller, Matthew; Moresi, Louis; Quenette, Steve; Zhang, Siqi

    2016-06-01

    The tectonic regime of a planet depends critically on the contributions of basal and internal heating to the planetary mantle, and how these evolve through time. We use viscoplastic mantle convection simulations, with evolving core-mantle boundary temperatures, and radiogenic heat decay, to explore how these factors affect tectonic regime over the lifetime of a planet. The simulations demonstrate (i) hot, mantle conditions, coming out of a magma ocean phase of evolution, can produce a "hot" stagnant-lid regime, whilst a cooler post magma ocean mantle may begin in a plate tectonic regime; (ii) planets may evolve from an initial hot stagnant-lid condition, through an episodic regime lasting 1-3 Gyr, into a plate-tectonic regime, and finally into a cold, senescent stagnant lid regime after ∼10 Gyr of evolution, as heat production and basal temperatures wane; and (iii) the thermal state of the post magma ocean mantle, which effectively sets the initial conditions for the sub-solidus mantle convection phase of planetary evolution, is one of the most sensitive parameters affecting planetary evolution - systems with exactly the same physical parameters may exhibit completely different tectonics depending on the initial state employed. Estimates of the early Earth's temperatures suggest Earth may have begun in a hot stagnant lid mode, evolving into an episodic regime throughout most of the Archaean, before finally passing into a plate tectonic regime. The implication of these results is that, for many cases, plate tectonics may be a phase in planetary evolution between hot and cold stagnant states, rather than an end-member.

  11. Europa - The prospects for an ocean

    NASA Technical Reports Server (NTRS)

    Reynolds, R. T.; Mckay, C. P.; Kasting, J. F.; Squires, S. W.

    1988-01-01

    Tidal dissipation in the satellites of a giant planet may provide sufficient heating to maintain a liquid water ocean below a thin ice layer. In the solar system, Europa, one of the Galilean satellites of Jupiter, may have such an ocean. Both theoretical calculations and certain observations support its existence, although proof is lacking. The putative ocean would probably have temperatures, pressures, and chemistry conducive to biologic activity. However, the environment would be severely energy limited. Possible energy sources include transient transmission of sunlight through fractures in the ice and hydrothermal activity on the ocean floor. While temporary conditions could exist that are within the range of adaptation of certain terrestrial organisms, origin of life under such conditions seems unlikely. In other solar systems, however, larger satellites with more significant heat flow could provide environments that are stable over an order of aeons and in which life could perhaps evolve.

  12. Elliptical instability in terrestrial planets and moons

    NASA Astrophysics Data System (ADS)

    Cebron, D.; Le Bars, M.; Moutou, C.; Le Gal, P.

    2012-03-01

    Context. The presence of celestial companions means that any planet may be subject to three kinds of harmonic mechanical forcing: tides, precession/nutation, and libration. These forcings can generate flows in internal fluid layers, such as fluid cores and subsurface oceans, whose dynamics then significantly differ from solid body rotation. In particular, tides in non-synchronized bodies and libration in synchronized ones are known to be capable of exciting the so-called elliptical instability, i.e. a generic instability corresponding to the destabilization of two-dimensional flows with elliptical streamlines, leading to three-dimensional turbulence. Aims: We aim here at confirming the relevance of such an elliptical instability in terrestrial bodies by determining its growth rate, as well as its consequences on energy dissipation, on magnetic field induction, and on heat flux fluctuations on planetary scales. Methods: Previous studies and theoretical results for the elliptical instability are re-evaluated and extended to cope with an astrophysical context. In particular, generic analytical expressions of the elliptical instability growth rate are obtained using a local WKB approach, simultaneously considering for the first time (i) a local temperature gradient due to an imposed temperature contrast across the considered layer or to the presence of a volumic heat source and (ii) an imposed magnetic field along the rotation axis, coming from an external source. Results: The theoretical results are applied to the telluric planets and moons of the solar system as well as to three Super-Earths: 55 CnC e, CoRoT-7b, and GJ 1214b. For the tide-driven elliptical instability in non-synchronized bodies, only the early Earth core is shown to be clearly unstable. For the libration-driven elliptical instability in synchronized bodies, the core of Io is shown to be stable, contrary to previously thoughts, whereas Europa, 55 CnC e, CoRoT-7b, and GJ 1214b cores can be unstable. The subsurface ocean of Europa is slightly unstable. However, these present states do not preclude more unstable situations in the past.

  13. THE ANGLO-AUSTRALIAN PLANET SEARCH. XXII. TWO NEW MULTI-PLANET SYSTEMS

    SciTech Connect

    Wittenmyer, Robert A.; Horner, J.; Salter, G. S.; Tinney, C. G.; Bailey, J.; Tuomi, Mikko; Zhang, Z.; Butler, R. P.; Jones, H. R. A.; O'Toole, S. J.; Carter, B. D.; Jenkins, J. S.; Vogt, S. S.; Rivera, Eugenio J.

    2012-07-10

    We report the detection of two new planets from the Anglo-Australian Planet Search. These planets orbit two stars each previously known to host one planet. The new planet orbiting HD 142 has a period of 6005 {+-} 427 days, and a minimum mass of 5.3 M{sub Jup}. HD 142c is thus a new Jupiter analog: a gas-giant planet with a long period and low eccentricity (e = 0.21 {+-} 0.07). The second planet in the HD 159868 system has a period of 352.3 {+-} 1.3 days and m sin i = 0.73 {+-} 0.05 M{sub Jup}. In both of these systems, including the additional planets in the fitting process significantly reduced the eccentricity of the original planet. These systems are thus examples of how multiple-planet systems can masquerade as moderately eccentric single-planet systems.

  14. Searching For Planets in "Holey Debris Disks"

    NASA Astrophysics Data System (ADS)

    Meshkat, Tiffany; Bailey, Vanessa P.; Su, Kate Y. L.; Kenworthy, Matthew A.; Mamajek, Eric E.; Hinz, Philip; Smith, Paul S.

    2015-01-01

    Directly imaging planets provides a unique opportunity to study young planets in the context of their formation and evolution. It examines the underlying semi-major axis exoplanet distribution and enables the characterization of the planet itself with spectroscopic examination of its emergent flux. However, only a handful of planets have been directly imaged, and thus the stars best suited for planet imaging are still a subject of debate. The "Holey Debris Disk" project was created in order to help determine if debris disks with gaps are signposts for planets. These gaps may be dynamically caused by planets accreting the debris material as they form. We present the results from our survey with VLT/NACO and the apodized phase plate coronagraph. We demonstrate that these disks with holes are good targets for directly detecting planets with the discovery of a planet around two of our targets, HD 95086 and HD 106906, at L'-band. Our non-detection of HD 95086 b in H-band demonstrates the importance of thermal infrared observations. The detected planets shepherd the outer cool debris belt. The relatively dust-free gap in these disks implies the presence of one or more closer-in planets. We discuss our new constraints on planets around other targets in our survey as well as disk properties of these targets and describe how future instruments will find the inner planets.

  15. Intestinal parasitosis in Nalout popularity, western Libya.

    PubMed

    Al Kilani, M K; Dahesh, S M; El Taweel, H A

    2008-04-01

    This paper studied gastrointestinal parasitosis in Nalout popularity. A hospital based study was done on a total of 800 stool samples from a private laboratory in Tigi city. The results showed an overall rate of 29.6%. Of these patients, 7.59% had double or triple parasitic infections. Children were more infected than adults. The parasites in a descending order were Entamoeba histolytica (21%), Enterobius vermicularis (7.5%), Giardia lamblia (2.5%), Balantidium coli (0.38%), and Hymenolepis nana (0.38%) A Sudanese immigrant employee had Strongyloides stercoralis larva in stool culture. PMID:19143135

  16. The Ocean.

    ERIC Educational Resources Information Center

    Broecker, Wallace S.

    1983-01-01

    The chemistry of the ocean, whose constituents interact with those of air and land to support life and influence climate, is known to have undergone changes since the last glacial epoch. Changes in dissolved oxygen, calcium ions, phosphate, carbon dioxide, carbonate ions, and bicarbonate ions are discussed. (JN)

  17. The International Deep Planet Survey

    NASA Astrophysics Data System (ADS)

    Marois, C.

    2010-10-01

    After completing the Gemini Deep Planet Survey (GDPS), an 86 young Sun-like/late-type star direct adaptive optics ADI imaging campaign, the International Deep Planet Survey was designed to complement the GDPS young late-type star sample by focusing mainly on early-type stars. The main idea behind the IDPS is that more early-type stars, being more massive, could harbor more massive and extended planetary disks, possibly forming more massive planets at wide separations -- partially compensating for their less favorable observing conditions (on average brighter, older and further away than late-type targets). I will present the overall IDPS survey (currently ongoing at Keck, Gemini North/South and VLT) and current statistics. I will also go over several software upgrades (data archive and ADI/SSDI data reduction tools) that are being implemented to prepare for the upcoming next generation order-of-magnitude larger campaigns that will be carried out with the Gemini Planet Imager.

  18. Return to the Red Planet

    NASA Technical Reports Server (NTRS)

    Lee, W.

    1996-01-01

    In November 1996, NASA and the Jet Propulsion Laboratory will begin America's return to Mars after a 20-year absence by launching the Mars Global Surveyor (MGS) spacecraft. This mission will usher in a new and exciting era of scientific missions to study the red planet.

  19. Giant Planets in Open Clusters

    NASA Astrophysics Data System (ADS)

    Quinn, S. N.; White, R. J.; Latham, D. W.

    2015-10-01

    Two decades after the discovery of 51 Peg b, more than 200 hot Jupiters have now been confirmed, but the details of their inward migration remain uncertain. While it is widely accepted that short period giant planets could not have formed in situ, several different mechanisms (e.g., Type II migration, planet-planet scattering, Kozai-Lidov cycles) may contribute to shrinking planetary orbits, and the relative importance of each is not well-constrained. Migration through the gas disk is expected to preserve circular, coplanar orbits and must occur quickly (within ˜ 10 Myr), whereas multi-body processes should initially excite eccentricities and inclinations and may take hundreds of millions of years. Subsequent evolution of the system (e.g., orbital circularization and inclination damping via tidal interaction with the host star) may obscure these differences, so observing hot Jupiters soon after migration occurs can constrain the importance of each mechanism. Fortunately, the well-characterized stars in young and adolescent open clusters (with known ages and compositions) provide natural laboratories for such studies, and recent surveys have begun to take advantage of this opportunity. We present a review of the discoveries in this emerging realm of exoplanet science, discuss the constraints they provide for giant planet formation and migration, and reflect on the future direction of the field.

  20. The Chemistry of the Planets.

    ERIC Educational Resources Information Center

    Blake, Peter

    1988-01-01

    Introduces knowledge of planetary chemistry for possible use in teaching. Discusses the chemical composition of the planets; the atmosphere and clouds of Venus, Jupiter and its moons, and Titan. Includes diagrams of the greenhouse effects in the solar system, elemental abundances, and the chemical composition of Jupiter. (RT)

  1. Jupiter: Lord of the Planets.

    ERIC Educational Resources Information Center

    Kaufmann, William

    1984-01-01

    Presents a chapter from an introductory college-level astronomy textbook in which full-color photographs and numerous diagrams highlight an extensive description of the planet Jupiter. Topics include Jupiter's geology, rotation, magnetic field, atmosphere (including clouds and winds), and the Great Red Spot. (DH)

  2. Finding Spring on Planet X

    ERIC Educational Resources Information Center

    Simoson, Andrew J.

    2007-01-01

    For a given orbital period and eccentricity, we determine the maximum time lapse between the winter solstice and the spring equinox on a planet. In addition, given an axial precession path, we determine the effects on the seasons. This material can be used at various levels to illustrate ideas such as periodicity, eccentricity, polar coordinates,…

  3. Magnetosphere of the outer planets

    NASA Technical Reports Server (NTRS)

    Kennel, C. F.

    1972-01-01

    Scaling laws for possible outer planet magnetospheres are derived. These suggest that convection and its associated auroral effects will play a relatively smaller role than at earth, and that there is a possibility that they could have significant radiation belts of energetic trapped particles.

  4. How Common are Habitable Planets?

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; DeVincenzi, Donald (Technical Monitor)

    2000-01-01

    The Earth is teeming with life, which, occupies a diverse array of environments; other bodies in our Solar System offer fewer, if any, niches which are habitable by life as we know it. Nonetheless, astronomical studies suggest that a large number of habitable planets-are likely to be present within our Galaxy.

  5. Finding Spring on Planet X

    ERIC Educational Resources Information Center

    Simoson, Andrew J.

    2007-01-01

    For a given orbital period and eccentricity, we determine the maximum time lapse between the winter solstice and the spring equinox on a planet. In addition, given an axial precession path, we determine the effects on the seasons. This material can be used at various levels to illustrate ideas such as periodicity, eccentricity, polar coordinates,

  6. Tracking Planets around the Sun

    ERIC Educational Resources Information Center

    Riddle, Bob

    2008-01-01

    In earlier columns, the celestial coordinate system of hour circles of right ascension and degrees of declination was introduced along with the use of an equatorial star chart (see SFA Star Charts in Resources). This system shows the planets' motion relative to the ecliptic, the apparent path the Sun follows during the year. An alternate system,

  7. Do Other Planets Have Summer?

    ERIC Educational Resources Information Center

    Nelson, George

    2005-01-01

    It's important to keep two things in mind when thinking about the cause of the seasons: (1) Earth and all the other planets except Pluto and Mercury move around the Sun in almost perfect circles, getting neither closer nor farther away from the Sun during the year; and (2) Earth's rotation axis is tilted with respect to the plane of its orbit

  8. Terrestrial Planet Finder: science overview

    NASA Technical Reports Server (NTRS)

    Unwin, Stephen C.; Beichman, C. A.

    2004-01-01

    The Terrestrial Planet Finder (TPF) seeks to revolutionize our understanding of humanity's place in the universe - by searching for Earth-like planets using reflected light, or thermal emission in the mid-infrared. Direct detection implies that TPF must separate planet light from glare of the nearby star, a technical challenge which has only in recent years been recognized as surmountable. TPF will obtain a low-resolution spectra of each planets it detects, providing some of its basic physical characteristics and its main atmospheric constituents, thereby allowing us to assess the likelihood that habitable conditions exist there. NASA has decided the scientific importance of this research is so high that TPF will be pursued as two complementary space observatories: a visible-light coronagraph and a mid-infrared formation flying interferometer. The combination of spectra from both wavebands is much more valuable than either taken separately, and it will allow a much fuller understanding of the wide diversity of planetary atmospheres that may be expected to exist. Measurements across a broad wavelength range will yield not only physical properties such as size and albedo, but will also serve as the foundations of a reliable and robust assessment of habitability and the presence of life.

  9. Tracking Planets around the Sun

    ERIC Educational Resources Information Center

    Riddle, Bob

    2008-01-01

    In earlier columns, the celestial coordinate system of hour circles of right ascension and degrees of declination was introduced along with the use of an equatorial star chart (see SFA Star Charts in Resources). This system shows the planets' motion relative to the ecliptic, the apparent path the Sun follows during the year. An alternate system,…

  10. Do Other Planets Have Summer?

    ERIC Educational Resources Information Center

    Nelson, George

    2005-01-01

    It's important to keep two things in mind when thinking about the cause of the seasons: (1) Earth and all the other planets except Pluto and Mercury move around the Sun in almost perfect circles, getting neither closer nor farther away from the Sun during the year; and (2) Earth's rotation axis is tilted with respect to the plane of its orbit…

  11. MEMS AO for Planet Finding

    NASA Technical Reports Server (NTRS)

    Rao, Shanti; Wallace, J. Kent; Shao, Mike; Schmidtlin, Edouard; Levine, B. Martin; Samuele, Rocco; Lane, Benjamin; Chakrabarti, Supriya; Cook, Timothy; Hicks, Brian; Jung, Paul

    2008-01-01

    This slide presentation reviews a method for planet finding using microelectromechanical systems (MEMS) Adaptive Optics (AO). The use of a deformable mirror (DM) is described as a part of the instrument that was designed with a nulling interferometer. The strategy that is used is described in detail.

  12. Venus and Mercury as Planets

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A general evolutionary history of the solar planetary system is given. The previously observed characteristics of Venus and Mercury (i.e. length of day, solar orbit, temperature) are discussed. The role of the Mariner 10 space probe in gathering scientific information on the two planets is briefly described.

  13. Formation of the terrestrial planets from planetesimals

    NASA Technical Reports Server (NTRS)

    Wetherill, George W.

    1991-01-01

    Formation of the terrestrial planets from planetesimals is discussed. The following subject areas are covered: (1) formation of the original planetesimals; (2) growth of planetesimals into planetary embryos; and (3) growth of runaway planetary embryos into terrestrial planets.

  14. The Geology of the Terrestrial Planets

    NASA Technical Reports Server (NTRS)

    Carr, M. H. (Editor); Saunders, R. S.; Strom, R. G.; Wilhelms, D. E.

    1984-01-01

    The geologic history of the terrestrial planets is outlined in light of recent exploration and the revolution in geologic thinking. Among the topics considered are planet formation; planetary craters, basins, and general surface characteristics; tectonics; planetary atmospheres; and volcanism.

  15. Tidal Dissipation in Extrasolar Planets

    NASA Astrophysics Data System (ADS)

    Pena, Fernando Gabriel

    2010-08-01

    Many known extra-solar giant planets lie close to their host stars. Around 60 have their semi-major axes smaller than 0.05 AU. In contrast to planets further out, the vast majority of these close-in planets have low eccentricity orbits. This suggests that their orbits have been circularized likely due to tidal dissipation inside the planets. These exoplanets share with our own Jupiter at least one trait in common: when they are subject to periodic tidal forcing, they behave like a lossy spring, with a tidal "quality factor", Q, of order 105. This parameter is the ratio between the energy in the tide and the energy dissipated per period. To explain this, a possible solution is resonantly forced internal oscillation. If the frequency of the tidal forcing happens to land on that of an internal eigenmode, this mode can be resonantly excited to a very large amplitude. The damping of such a mode inside the planet may explain the observed Q value. The only normal modes that fall in the frequency range of the tidal forcing ( few days) are inertial modes, modes restored by the Coriolis force. We present a new numerical technique to solve for inertial modes in a convective, rotating sphere. This technique combines the use of an ellipsoidal coordinate system with a pseudo-spectral method to solve the partial differential equation that governs the inertial oscillations. We show that, this technique produces highly accurate solutions when the density profile is smooth. In particular, the lines of nodes are roughly parallel to the ellipsoidal coordinate axes. In particular, using these accurate solutions, we estimate the resultant tidal dissipation for giant planets, and find that turbulent dissipation of inertial modes in planets with smooth density profiles do not give rise to dissipation as strong as the one observed. We also study inertial modes in density profiles that exhibit discontinuities, as some recent models of Jupiter show. We found that, in this case, our method could not produce convergent solutions for the inertial modes. Additionally, we propose a way to observe inertial modes inside Saturn indirectly, by observing waves in its rings that may be excited by inertial modes inside Saturn.

  16. Oceanic Plateaus

    NASA Astrophysics Data System (ADS)

    Kerr, A. C.

    2003-12-01

    Although the existence of large continental flood basalt provinces has been known for some considerable time, e.g., Holmes (1918), the recognition that similar flood basalt provinces also exist below the oceans is relatively recent. In the early 1970s increasing amounts of evidence from seismic reflection and refraction studies revealed that the crust in several large portions of the ocean floor is significantly thicker than "normal" oceanic crust, which is 6-7 km thick. One of the first areas of such over-thickened crust to be identified was the Caribbean plate ( Edgar et al., 1971) which Donnelly (1973) proposed to be an "oceanic flood basalt province". The term oceanic plateau was coined by Kroenke (1974), and was prompted by the discovery of a large area of thickened crust (>30 km) in the western Pacific known as the Ontong Java plateau (OJP). As our knowledge of the ocean basins has improved over the last 25 years, many more oceanic plateaus have been identified ( Figure 1). Coffin and Eldholm (1992) introduced the term "large igneous provinces" (LIPs) as a generic term encompassing oceanic plateaus, continental flood basalt provinces, and those provinces which form at the continent-ocean boundary (volcanic rifted margins). (22K)Figure 1. Map showing all major oceanic plateaus, and other large igneous provinces discussed in the text (after Saunders et al., 1992). LIPs are generally believed to be formed by decompression melting of upwelling hotter mantle, known as mantle plumes. Although ideas about hotpots and mantle plumes have been around for almost 40 years (Wilson, 1963), it is only in the past 15 years that LIPs have become the focus of major research. One of the main reasons for the increased research activity into LIPs is the realization that significant proportions of these LIPs erupted over a relatively short time, often less than 2-3 Myr (see review in Coffin, 1994). This has important implications for mantle processes and source regions ( Hart et al., 1992; Stein and Hofmann, 1994), as well as environmental effects on the global biosphere (e.g., Caldeira and Rampino, 1990; Courtillot et al., 1996; Kerr, 1998). Oceanic plateaus can also become accreted to continental margins, and it has been proposed that these plateaus have been significant contributors to the growth of continental crust (e.g., Abbott, 1996; Albarede, 1998).The most recent major phase of oceanic plateau formation was in the Cretaceous when the Ontong Java, Manihiki, Hess Rise, and the Caribbean-Colombian plateaus formed in the Pacific, while in the Indian Ocean the Kerguelen plateau was developing. The areas, volume maximum thicknesses and ages of the larger of these plateaus are given in Table 1. The Ontong Java is the largest of the Cretaceous plateaus. It covers an area of 1.9×106 km2, and has an estimated total volume of 4.4×107 km3 (Eldholm and Coffin, 2000). Although early seismic refraction data suggested that the OJP was as thick as 43 km ( Furomoto et al., 1976), a more recent synthesis based on existing seismic and new gravity data ( Gladczenko et al., 1997) has indicated the average thickness to be ˜32 km. Table 1. Ages and dimensions of Jurassic-Cretaceous oceanic plateaus Oceanic plateauMean age (Ma)Area (106 km2)Thickness range (km)Volume (106 km3) Hikurangiearly-mid Cretaceous0.710-152.7 Shatsky Rise1470.210-282.5 Magellan Rise1450.5101.8 Manihiki1230.8>208.8 Ontong Java121(90)1.915-3244.4 Hess Rise990.8>159.1 Caribbean881.18-204.4 South Kerguelen1101.0˜226.0 Central Kerguelen/Broken Ridge861.019-219.1 Sierra Leone Rise˜730.9>102.5 Maud Rise˜>730.2>101.2 After Eldholm and Coffin (2000).

  17. A Quantitative Criterion for Defining Planets

    NASA Astrophysics Data System (ADS)

    Margot, Jean-Luc

    2015-12-01

    A simple metric can be used to determine whether a planet or exoplanet can clear its orbital zone during a characteristic time scale, such as the lifetime of the host star on the main sequence. This criterion requires only estimates of star mass, planet mass, and orbital period, making it possible to immediately classify 99% of all known exoplanets. All eight planets and all classifiable exoplanets satisfy the criterion. This metric may be useful in generalizing and simplifying the definition of a planet.

  18. The Use of Planisphere to Locate Planets

    ERIC Educational Resources Information Center

    Kwok, Ping-Wai

    2013-01-01

    Planisphere is a simple and useful tool in locating constellations of the night sky at a specific time, date and geographic location. However it does not show the planet positions because planets are not fixed on the celestial sphere. It is known that the planet orbital planes are nearly coplanar and close to the ecliptic plane. By making

  19. Effect of Unseen Planets on Secular Interactions

    NASA Astrophysics Data System (ADS)

    Van Laerhoven, Christa L.

    2016-05-01

    A great number of multi-planet extra-solar systems are now known thanks to both transit and radial velocity surveys. The long-term eccentricity and inclination behavior of many of these systems is readily described by classical second-order secular theory in which the eccentricity and inclination of each planet is a sum of contributions from several eigenmodes. The underlying structure of the eigenmodes, that is, how much each planet is affected by a given eigenmode, depends on only the masses and semi-major axes of the planets, and the mass of the star. When discerning the dynamics of a system it is usually assumed that the known planets are the only planets in the system, or at least that any other planets are distant enough to not strongly affect the known planets. However, the secular structure might change significantly if there are one or more additional, unseen planets in the system. I will discuss how the secular structure of several observed multi-planet systems changes when an additional planet is added to the system, and how that change in the secular structure depends on the mass and distance of the additional planet.

  20. The Use of Planisphere to Locate Planets

    ERIC Educational Resources Information Center

    Kwok, Ping-Wai

    2013-01-01

    Planisphere is a simple and useful tool in locating constellations of the night sky at a specific time, date and geographic location. However it does not show the planet positions because planets are not fixed on the celestial sphere. It is known that the planet orbital planes are nearly coplanar and close to the ecliptic plane. By making…

  1. Progress in extra-solar planet detection

    NASA Technical Reports Server (NTRS)

    Brown, Robert A.

    1991-01-01

    Progress in extra-solar planet detection is reviewed. The following subject areas are covered: (1) the definition of a planet; (2) the weakness of planet signals; (3) direct techniques - imaging and spectral detection; and (4) indirect techniques - reflex motion and occultations.

  2. Flow of Planets, Not Weak Tidal Evolution, Produces the Short-Period Planet Distribution with More Planets than Expected

    NASA Astrophysics Data System (ADS)

    Taylor, Stuart F.

    2013-01-01

    The most unexpected planet finding is arguably the number of those with shorter periods than theorists had expected, because most such close planets had been expected to migrate into the star in shorter timescales than the ages of the stars. Subsequent effort has been made to show how tidal dissipation in stars due to planets could be weaker than expected, but we show how the occurrence distribution of differently-sized planets is more consistent with the explanation that these planets have more recently arrived as a flow of inwardly migrating planets, with giant planets more likely to be found while gradually going through a short period stage. This continual ``flow'' of new planets arriving from further out is presumably supplied by the flow likely responsible for the short period pileup of giant planets (Socrates+ 2011). We have previously shown that the shortest period region of the exoplanet occurrence distribution has a fall-off shaped by inward tidal migration due to stellar tides, that is, tides on the star caused by the planets (Taylor 2011, 2012). The power index of the fall-off of giant and intermediate radius planet candidates found from Kepler data (Howard+ 2011) is close to the index of 13/3 which is expected for planets in circular orbits undergoing tidal migration. However, there is a discrepancy of the strength of the tidal migration determined using fits to the giant and medium planets distributions. This discrepancy is best resolved by the explanation that more giant than medium radii planets migrate through these short period orbits. We also present a correlation between higher eccentricity of planetary orbits with higher Fe/H of host stars, which could be explained by high eccentricity planets being associated with recent episodes of other planets into stars. By the time these planets migrate to become hot Jupiters, the pollution may be mixed into the star. The clearing of other planets by migrating hot giant planets may result in hot Jupiters being anti-correlated with additional planets. We present results from our study of inward migration.

  3. Search for Terrestrial Planets with SIM Planet Quest

    NASA Technical Reports Server (NTRS)

    Shao, Michael; Tanner, Angelle M.; Catanzarite, Joseph H.

    2006-01-01

    SIM is an astrometric mission that will be capable of 1 microarcsec relative astrometric accuracy in a single measurement of approx.1000 sec. The search for terrestrial planets in the habitable zone around nearby stars is one of the main science goals of the project. In 2001, NASA through the peer review process selected 10 key projects, two of which had as its goal, the search for terrestrial planets around nearby stars. The two teams, one led by G. Marcy (UC Berkeley) and one lead by M. Shao (JPL), have an extensive preparatory science program underway. This paper describes the status of this activity as well as the technology status of SIM's narrow angle astrometry capability, to reach 1 uas in a single epoch measure and its ability to average multiple epoch measurements to well below 1 uas.

  4. The Earth: A Changing Planet

    NASA Astrophysics Data System (ADS)

    Ribas, Núria; Màrquez, Conxita

    2013-04-01

    text: We describe a didactic unit that rises from our own living impression about our experience on the planet. Most of us feel the Earth to be a very static place. Rocks don't easily move and most landscapes always look the same over time. Anyone would say (the same way most scientists believed until the beginning of the last century) that our planet has always remained unchanged, never transformed. But then, all of a sudden, as a misfortune for so many humans, natural hazards appear on the scene: an earthquake causing so many disasters, a tsunami carrying away everything in its path, an eruption that can destroy huge surrounding areas but also bring new geographical relief. Science cannot remain oblivious to these events, we must wonder beyond. What does an earthquake mean? Why does it happen? What about an eruption? If it comes from the inside, what can we guess from it? Researching about all of these events, scientists have been able to arrive to some important knowledge of the planet itself: It has been possible to theorize about Earth's interior. It has also been confirmed that the planet has not always been the quiet and stable place we once thought. Continents, as Wegener supposed, do move about and the Tectonic Plates Theory, thanks to the information obtained through earthquakes and eruption, can provide some interesting explanations. But how do we know about our planet's past? How can we prove that the Earth has always been moving and that its surface changes? The Earth's rocks yield the answer. Rocks have been the only witnesses throughout millions of years, since the planet first came to existence. Let's learn how to read them… Shouldn't we realize that rocks are to Geology what books are to History? This discursive process has been distributed in four learning sequences: 1. Land is not as solid nor firm as it would seem, 2. The Earth planet: a puzzle, 3. The rocks also recycle , 4. Field trip to "Sant Miquel del Fai". The subjects take about 30 hours of class time for students from 13 to 14 years of age. During the learning process, different methodological tools of teaching and learning have been used. After reading and understanding news about natural disasters such as earthquakes and eruptions, cooperative group work and an oral presentation are prepared. In addition, it has been very useful to follow-up with some web simulations to predict natural phenomena, which can then be tested in the laboratory. Finally, the students apply their new understanding on a visit to a geological formation, where applying the language learned by observing the rocks, they demonstrate that the planet Earth has changed over the course of many millions of years. Natural hazards are a small and timely demonstration of the ability to change our planet.

  5. Global Warming: The Threat to the Planet

    NASA Astrophysics Data System (ADS)

    Hansen, James

    2007-04-01

    Paleoclimate data show that the Earth's climate is remarkably sensitive to global forcings. Positive feedbacks predominate. This allows the entire planet to be whipsawed between climate states. One feedback, the `albedo flip' property of water substance, provides a powerful trigger mechanism. A climate forcing that `flips' the albedo of a sufficient portion of an ice sheet can spark a cataclysm. Ice sheet and ocean inertia provides only moderate delay to ice sheet disintegration and a burst of added global warming. Recent greenhouse gas (GHG) emissions place the Earth perilously close to dramatic climate change that could run out of our control, with great dangers for humans and other creatures. CO2 is the largest human-made climate forcing, but CH4, O3, N2O and black carbon (BC) are important. Only intense simultaneous efforts to slow CO2 emissions and reduce non-CO2 forcings can keep climate within or near the range of the past million years. Some forcings are especially effective at high latitudes, so concerted efforts to reduce their emissions could still ``save the Arctic,'' while also having major benefits for human health, agricultural productivity, and the global environment.

  6. Planet Detection Algorithms for the Terrestrial Planet Finder-C

    NASA Astrophysics Data System (ADS)

    Kasdin, N. J.; Braems, I.

    2005-12-01

    Critical to mission planning for the terrestrial planet finder coronagraph (TPF-C) is the ability to estimate integration times for planet detection. This detection is complicated by the presence of background noise due to local and exo-zodiacal dust, by residual speckle due optical errors, and by the dependence of the PSF shape on the specific coronagraph. In this paper we examine in detail the use of PSF fitting (matched filtering) for planet detection, derive probabilistic bounds for the signal-to-noise ratio by balancing missed detection and false alarm rates, and demonstrate that this is close to the optimal linear detection technique. We then compare to a Bayesian detection approach and show that for very low background the Bayesian method offers integration time improvements, but rapidly approaches the PSF fitting result for reasonable levels of background noise. We confirm via monte-carlo simulations. This work was supported under a grant from the Jet Propulsion Laboratory and by a fellowship from the Institut National de Recherche en Informatique et Automatique (INRIA).

  7. Hot Jupiters from secular planet-planet interactions.

    PubMed

    Naoz, Smadar; Farr, Will M; Lithwick, Yoram; Rasio, Frederic A; Teyssandier, Jean

    2011-05-12

    About 25 per cent of 'hot Jupiters' (extrasolar Jovian-mass planets with close-in orbits) are actually orbiting counter to the spin direction of the star. Perturbations from a distant binary star companion can produce high inclinations, but cannot explain orbits that are retrograde with respect to the total angular momentum of the system. Such orbits in a stellar context can be produced through secular (that is, long term) perturbations in hierarchical triple-star systems. Here we report a similar analysis of planetary bodies, including both octupole-order effects and tidal friction, and find that we can produce hot Jupiters in orbits that are retrograde with respect to the total angular momentum. With distant stellar mass perturbers, such an outcome is not possible. With planetary perturbers, the inner orbit's angular momentum component parallel to the total angular momentum need not be constant. In fact, as we show here, it can even change sign, leading to a retrograde orbit. A brief excursion to very high eccentricity during the chaotic evolution of the inner orbit allows planet-star tidal interactions to rapidly circularize that orbit, decoupling the planets and forming a retrograde hot Jupiter. PMID:21562558

  8. Oceanic Lidar

    NASA Technical Reports Server (NTRS)

    Carder, K. L. (Editor)

    1981-01-01

    Instrument concepts which measure ocean temperature, chlorophyll, sediment and Gelbstoffe concentrations in three dimensions on a quantitative, quasi-synoptic basis were considered. Coastal zone color scanner chlorophyll imagery, laser stimulated Raman temperaure and fluorescence spectroscopy, existing airborne Lidar and laser fluorosensing instruments, and their accuracies in quantifying concentrations of chlorophyll, suspended sediments and Gelbstoffe are presented. Lidar applications to phytoplankton dynamics and photochemistry, Lidar radiative transfer and signal interpretation, and Lidar technology are discussed.

  9. Social Intelligence and Academic Achievement as Predictors of Adolescent Popularity

    ERIC Educational Resources Information Center

    Meijs, Noortje; Cillessen, Antonius H. N.; Scholte, Ron H. J.; Segers, Eliane; Spijkerman, Renske

    2010-01-01

    This study compared the effects of social intelligence and cognitive intelligence, as measured by academic achievement, on adolescent popularity in two school contexts. A distinction was made between sociometric popularity, a measure of acceptance, and perceived popularity, a measure of social dominance. Participants were 512, 14-15 year-old…

  10. The Use of Popular Science Articles in Teaching Scientific Literacy

    ERIC Educational Resources Information Center

    Parkinson, Jean; Adendorff, Ralph

    2004-01-01

    This article considers the use of popular science articles in teaching scientific literacy. Comparing the discourse features of popular science with research article and textbook science--the last two being target forms for students--it argues that popular science articles cannot serve as models for scientific writing. It does, however, suggest…

  11. The Sociology of Popular Culture: Looking Backwards and Forwards.

    ERIC Educational Resources Information Center

    Meyersohn, Rolf

    This article discusses the field of study of popular culture and traces its history from 1930 to the present. The study of popular culture consists of examining all elements of human activity and life style, including knowledge, belief, art, and customs that are common to a large group. These popular culture elements have been disseminated mainly,…

  12. The Role of Attractiveness and Aggression in High School Popularity

    ERIC Educational Resources Information Center

    Borch, Casey; Hyde, Allen; Cillessen, Antonius H. N.

    2011-01-01

    This study examines the effects of physical attractiveness and aggression on popularity among high school students. Previous work has found positive relationships between aggression and popularity and physical attractiveness and popularity. The current study goes beyond this work by examining the interactive effects of physical attractiveness and…

  13. Teaching Popular Music in Finland: What's Up, What's Ahead?

    ERIC Educational Resources Information Center

    Vakeva, Lauri

    2006-01-01

    This article describes the history and current situation of popular music pedagogy in Finland. While popular music is widely accepted in the curriculum, there are differences in its application in the comprehensive schools and music institutions. Popular styles were first introduced into Finnish music education by secondary school music teachers;…

  14. The Attributes Adolescents Associate with Peer Popularity and Teacher Preference.

    ERIC Educational Resources Information Center

    Gorman, Andrea Hopmeyer; Kim, Janna; Schimmelbusch, Anne

    2002-01-01

    Investigates perceived popularity and teacher preference in a sample of 351 10th-graders. Analyses revealed that different behaviors were associated with perceived popularity and teacher preference. Low GPA, low submissiveness, and high rates of absenteeism were associated with high perceived popularity and a low perceived teacher preference.…

  15. The Use of Popular Science Articles in Teaching Scientific Literacy

    ERIC Educational Resources Information Center

    Parkinson, Jean; Adendorff, Ralph

    2004-01-01

    This article considers the use of popular science articles in teaching scientific literacy. Comparing the discourse features of popular science with research article and textbook science--the last two being target forms for students--it argues that popular science articles cannot serve as models for scientific writing. It does, however, suggest

  16. Popular Education and Social Movements in Scotland Today.

    ERIC Educational Resources Information Center

    Crowther, Jim, Ed.; Martin, Ian, Ed.; Shaw, Mae, Ed.

    The following papers are included: "Foreword" (Colin Kirkwood); "Introductory Essay: Popular Education and Social Movements in Scotland Today" (Ian Martin); "Popular Education and the Struggle for Democracy" (Jim Crowther); "Social Movements and the Politics of Educational Change" (Lindsay Paterson); "Learning from Popular Education in Latin…

  17. Producing "Postman Pat": The Popular Cultural Construction of Idyllic Rurality

    ERIC Educational Resources Information Center

    Horton, John

    2008-01-01

    This paper concerns the popular cultural representation of English rurality. It focuses upon "Postman Pat", a popular cultural phenomenon which has come to be routinely cited as exemplary and iconic of contemporary imaginings of the English countryside as "idyllic". The idea that Anglocentric popular culture (re)produces this sort of "rural…

  18. Teaching Popular Music in Finland: What's Up, What's Ahead?

    ERIC Educational Resources Information Center

    Vakeva, Lauri

    2006-01-01

    This article describes the history and current situation of popular music pedagogy in Finland. While popular music is widely accepted in the curriculum, there are differences in its application in the comprehensive schools and music institutions. Popular styles were first introduced into Finnish music education by secondary school music teachers;

  19. Inspiration Today: Music, Astronomy, and Popular Culture

    NASA Astrophysics Data System (ADS)

    Fraknoi, A.

    2016-01-01

    We explore a variety of examples of music inspired by serious astronomy (as opposed to simply an astronomical title or quick allusion to spooning in June to the light of the Moon). The examples are drawn from my recently published catalog of 133 such pieces, including both classical and popular genres of music. We discuss operas based on the life and work of astronomers, six songs based on a reasonable understanding of the properties of black holes, constellation pieces written by composers from around the world who are or were active amateur astronomers, the song that compares walking on the Moon to being in love, the little-known rock song that became a reference in the Astrophysical Journal, pieces that base the patterns of the music on the rhythms of astronomical phenomena, and a number of others.

  20. Breastfeeding and popular aetiology in the Sahel.

    PubMed

    van de Walle, E; van de Walle, F

    1991-04-01

    Two views about breastfeeding and the resumption of intercourse after a birth are found to prevail in Bamako and Bobo-Dioulasso, two cities of the Sahel region of Africa: that sexual relations may spoil the milk; and that a child should be weaned when the woman is pregnant again. Both beliefs provide a rationale to abstain, but the postpartum taboo has been greatly reduced in the area, and the second belief is the most important. 'Bad milk' serves as an explanation for many of the diarrhoeas and diseases of nutritional origin that affect infants and children. Traditional medical treatments of diarrhoea and protein calorie malnutrition are consistent with the popular aetiology. The acceptance of modern techniques of infant care in this area may well be predicated on the diffusion of an alternative model of disease causation. PMID:10148804

  1. Structure of Science Popularizations: A Genre-Analysis Approach to the Schema of Popularized Medical Texts.

    ERIC Educational Resources Information Center

    Nwogu, Kevin N.

    1991-01-01

    Attempts to characterize one discourse type of science popularization, the Journalistic Reported Version (JRV) of research articles in science magazines and newspapers. Results indicate that the JRV has an identifiable schema by which the information it contains is structured, and a typical JRV text may have as many as nine schematic structures.…

  2. Planet X : The Search for an Illusion

    NASA Astrophysics Data System (ADS)

    McGaha, J.

    2006-10-01

    The search for Planet X began soon after the discovery of Uranus in 1781. The scientific search, over the next 200 years, resulted in the discovery of many new "Objects" (Planets and Minor Planets) but not the elusive Planet X. The data now indicate there never was a Planet X to find and the scientific search ended in the early 1990's. In the last 10 years the search has begun anew, not by scientists, interested in adding to our knowledge, but by groups advocating apocalyptic ideas. They have a wide following and are interested in promoting their pseudoscientific beliefs. This talk will discuss this history.

  3. Proceedings of Protostars and Planets V

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Oral presentation sessions in this conference include: Clouds and cores; Star formation and protostars; Binaries and multiples; Newborn massive stars; jets and outflows; Clusters and associations; T Tauri stars and disks; Brown dwarfs; Planet formation and evolution; Extrasolar planets; Dust and protoplanetary disks; Early solar system and Astrobiology. Poster presentations included: Clouds and Cores. Collapse and Protostars, Binaries and Multiples, Clusters, Associations, and the IMF, Jets and Outflows, T Tauri Stars and Other Young Stars, Disks and Disk Accretion, Brown Dwarfs, Herbig Ae/Be Stars and Massive Stars, Solar System Objects, Planet Formation, Extrasolar Planets and Planet Detection, Properties of Protoplanetary Disks, Migration and Planetary Orbits and Meteoritics and Astrobiology

  4. ORBITAL DISTRIBUTIONS OF CLOSE-IN PLANETS AND DISTANT PLANETS FORMED BY SCATTERING AND DYNAMICAL TIDES

    SciTech Connect

    Nagasawa, M.; Ida, S.

    2011-12-01

    We investigated the formation of close-in planets (hot Jupiters) by a combination of mutual scattering, Kozai effect, and tidal circularization, through N-body simulations of three gas giant planets, and compared the results with discovered close-in planets. We found that in about 350 cases out of 1200 runs ({approx}30%), the eccentricity of one of the planets is excited highly enough for tidal circularization by mutual close scatterings followed by secular effects due to outer planets, such as the Kozai mechanism, and the planet becomes a close-in planet through the damping of eccentricity and semimajor axis. The formation probability of close-in planets by such scattering is not affected significantly by the effect of the general relativity and inclusion of inertial modes in addition to fundamental modes in the tides. Detailed orbital distributions of the formed close-in planets and their counterpart distant planets in our simulations were compared with observational data. We focused on the possibility for close-in planets to retain non-negligible eccentricities ({approx}> 0.1) on timescales of {approx}10{sup 9} yr and have high inclinations, because close-in planets in eccentric or highly inclined orbits have recently been discovered. In our simulations we found that as many as 29% of the close-in planets have retrograde orbits, and the retrograde planets tend to have small eccentricities. On the other hand, eccentric close-in planets tend to have orbits of small inclinations.

  5. Effects of Water Amount on the Surface Environment of Terrestrial Planets: High Pressure Ice and Carbon Cycle

    NASA Astrophysics Data System (ADS)

    Nakayama, Akifumi; Abe, Yutaka

    2015-12-01

    Terrestrial planets with several wt% of H2O in extrasolar planetary systems are theoretically predicted in the habitable zone [Raymond et al., 2004]. Such planets are expected to be covered by an ocean entirely (called as “ocean planets”). Amount of atmospheric CO2 (PCO2) is important for surface environment because CO2 is a strong greenhouse gas. PCO2 is determined by a race between degassing and sink through weathering on carbon cycle. On an ocean planet, seafloor weathering is important because continental weathering can’t work [Abbot et al., 2012]. In addition, ocean planets with large water amount may have high-pressure (HP) ice on the seafloor [Leger et al., 2004]. Since the ocean floor is covered by ice in such case, it has been thought that any weathering processes will not work and PCO2 will be extremely high. When plate tectonics works, heat flow from oceanic crust decreases with distance from the mid ocean ridge. Therefore, HP ice near the mid ocean ridge will be kept solid-liquid coexistent state at the melting point because of high heat flow. Seafloor weathering works in this region. The seafloor weathering under this condition efficiently works because weathering temperature is kept melting point regardless of surface temperature. Thus, our aim is to clarify the relationship between water amount and surface environment focusing seafloor environment. We develop a carbon cycle model considering the seafloor weathering. Our major assumptions are following; 1) Earth-sized ocean planets with various water amount, 2) Degassing rate is depended on the total amount of carbon and total carbon inventory is proportional to the surface water amount. We investigated thermal state of HP ice and determined effective weathering region where HP ice is coexistent with water, then we investigated the PCO2 in equilibrium state where degassing and regassing are balanced. As a result, forming of HP ice may cause snowball state due to high weathering rate. When solar incident flux and heat flow from mantle are the present Earth’s value and a ratio of CO2 / H2O inventory is carbonaceous chondrite composition, a planet with large ocean which is larger than 90 Earth’s ocean mass lapses into snowball state. It was previously believed that forming of HP ice supports warm climate; rather, forming of HP ice could cause snowball state.

  6. Earth's Energy Imbalance and Ocean Heat Storage

    NASA Astrophysics Data System (ADS)

    Hansen, J.; Willis, J.; Leuliette, E.; Bleck, R.; Lo, K.; Ruedy, R.; Sato, M.; Sun, S.

    2006-12-01

    The Earth's energy imbalance, i.e., the difference between solar energy absorbed and thermal energy emitted by the planet, is fundamental to global climate change, as it measures the net forcing acting on the climate system. The imbalance is now positive on decadal time scales, due to dominance of increasing greenhouse gas (GHG) forcing, and, with canonical climate sensitivity, it yields an estimate of the amount of global warming that remains "in the pipeline" due to GHGs already in the atmosphere. The ocean is the largest sink for excess incoming energy. Inference of information from the energy imbalance is affected by a trade-off between decreasing accuracy of earlier data and the added information from longer time scales. We use two atmosphere-ocean models, with ocean heat and sea level measurements, to study the roles of different climate forcings, unforced climate variability including ocean- cloud interactions, and limitations of data sampling. We find that observed decrease in ocean heat content in the upper 750m in 2004-2005 does not significantly alter the estimate of ~0.5C global warming still "in the pipeline". Continuation and refinement of measurements of ocean heat, sea level, and ice sheet mass balance have the potential to greatly refine understanding of global warming, its practical implications, and important climate processes, but to be most useful they need to be supplemented by better measurements of deep ocean heat content changes and precise measurements of changing climate forcings such as tropospheric aerosols.

  7. Formation of Giant Planets and Brown Dwarves

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.

    2003-01-01

    According to the prevailing core instability model, giant planets begin their growth by the accumulation of small solid bodies, as do terrestrial planets. However, unlike terrestrial planets, the growing giant planet cores become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. Models predict that rocky planets should form in orbit about most stars. It is uncertain whether or not gas giant planet formation is common, because most protoplanetary disks may dissipate before solid planetary cores can grow large enough to gravitationally trap substantial quantities of gas. Ongoing theoretical modeling of accretion of giant planet atmospheres, as well as observations of protoplanetary disks, will help decide this issue. Observations of extrasolar planets around main sequence stars can only provide a lower limit on giant planet formation frequency . This is because after giant planets form, gravitational interactions with material within the protoplanetary disk may cause them to migrat inwards and be lost to the central star. The core instability model can only produce planets greater than a few jovian masses within protoplanetary disks that are more viscous than most such disks are believed to be. Thus, few brown dwarves (objects massive enough to undergo substantial deuterium fusion, estimated to occur above approximately 13 jovian masses) are likely to be formed in this manner. Most brown dwarves, as well as an unknown number of free-floating objects of planetary mass, are probably formed as are stars, by the collapse of extended gas/dust clouds into more compact objects.

  8. Ocean Currents: Marine Science Activities for Grades 5-8. Teacher's Guide.

    ERIC Educational Resources Information Center

    Halversen, Catherine; Beals, Kevin; Strang, Craig

    This teacher's guide attempts to answer questions such as: What causes ocean currents? What impact do they have on Earth's environment? and How have they influenced human history? Seven innovative activities are provided in which students can gain fascinating insights into the earth as the ocean planet. Activities focus on how wind, temperature,…

  9. Ocean Currents: Marine Science Activities for Grades 5-8. Teacher's Guide.

    ERIC Educational Resources Information Center

    Halversen, Catherine; Beals, Kevin; Strang, Craig

    This teacher's guide attempts to answer questions such as: What causes ocean currents? What impact do they have on Earth's environment? and How have they influenced human history? Seven innovative activities are provided in which students can gain fascinating insights into the earth as the ocean planet. Activities focus on how wind, temperature,

  10. Terrestrial versus giant planet formation

    NASA Technical Reports Server (NTRS)

    Boss, Alan P.

    1988-01-01

    Given a solar nebular surrounding the early protosun, containing dust grains that have already undergone growth through collisions to about centimeter-size, the question of the formation of the terrestrial and giant planets is considered. In contrast to the usual approach of emphasizing how well a problem is understood, the uncertainties and areas where more work needs to be done will be accentuated. Also, the emphasis will be on the dynamics of planetary formation, because profound problems still exist in this area, and because it seems most logical to concentrate first on the dynamical questions involved with assembling the planets before putting too much effort into the detailed chemical and geological consequences of certain formation mechanisms.

  11. Ionospheres of the terrestrial planets

    NASA Astrophysics Data System (ADS)

    Schunk, R. W.; Nagy, A. F.

    1980-11-01

    The theory and observations relating to the ionospheres of the terrestrial planets Venus, the earth, and Mars are reviewed. Emphasis is placed on comparing the basic differences and similarities between the planetary ionospheres. The review covers the plasma and electric-magnetic field environments that surround the planets, the theory leading to the creation and transport of ionization in the ionospheres, the relevant observations, and the most recent model calculations. The theory section includes a discussion of ambipolar diffusion in a partially ionized plasma, diffusion in a fully ionized plasma, supersonic plasma flow, photochemistry, and heating and cooling processes. The sections on observations and model calculations cover the neutral atmosphere composition, the ion composition, the electron density, and the electron, ion, and neutral temperatures.

  12. MESSENGER: Exploring the Innermost Planet

    NASA Astrophysics Data System (ADS)

    Solomon, S. C.

    2011-12-01

    One of Earth's closest planetary neighbors, Mercury remained comparatively unexplored for the more than three decades that followed the three flybys of the innermost planet by the Mariner 10 spacecraft in 1974-75. Mariner 10 imaged 45% of Mercury's surface at about 1 km/pixel average resolution, confirmed Mercury's anomalously high bulk density and implied large fractional core size, discovered Mercury's internal magnetic field, documented that H and He are present in the planet's tenuous exosphere, and made the first exploration of Mercury's magnetosphere and solar wind environment. Ground-based astronomers later reported Na, K, and Ca in Mercury's exosphere; the presence of deposits in the floors of polar craters having radar characteristics best matched by water ice; and strong evidence from the planet's forced libration amplitude that Mercury has a fluid outer core. Spacecraft exploration of Mercury resumed with the selection for flight, under NASA's Discovery Program, of the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission. Launched in 2004, MESSENGER flew by the innermost planet three times in 2008-2009 en route to becoming the first spacecraft to orbit Mercury in March of this year. MESSENGER's first chemical remote sensing measurements of Mercury's surface indicate that the planet's bulk silicate fraction differs from those of the other inner planets, with a low-Fe surface composition intermediate between basalts and ultramafic rocks and best matched among terrestrial rocks by komatiites. Moreover, surface materials are richer in the volatile constituents S and K than predicted by most planetary formation models. Global image mosaics and targeted high-resolution images (to resolutions of 10 m/pixel) reveal that Mercury experienced globally extensive volcanism, including large expanses of plains emplaced as flood lavas and widespread examples of pyroclastic deposits likely emplaced during explosive eruptions of volatile-bearing magmas. Bright deposits within impact craters host fresh-appearing, rimless depressions or hollows, often displaying high-reflectance interiors and halos and likely formed through processes involving the geologically recent loss of volatiles. The tectonic history of Mercury, although dominated by near-global contractional deformation as first seen by Mariner 10, is more complex than first appreciated, with numerous examples of extensional deformation that accompanied impact crater and basin modification. Mercury's magnetic field is dominantly dipolar, but the field is axially symmetric and equatorially asymmetric, a geometry that poses challenges to dynamo models for field generation. The interaction between the solar wind and Mercury's magnetosphere, among the most dynamic in the solar system, serves both to replenish the exosphere and space weather the planet's surface. Plasma ions of planetary origin are seen throughout the sampled volume of Mercury's magnetosphere, with maxima in heavy-ion fluxes in the planet's magnetic-cusp regions. Bursts of energetic electrons, seen at most local times, point to an efficient acceleration mechanism operating within Mercury's magnetosphere on a regular basis that produces electrons with energies up to hundreds of keV on timescales of seconds.

  13. Planet-crossing asteroid survey

    NASA Technical Reports Server (NTRS)

    Wilder, P. D.

    1984-01-01

    The planet-crossing asteroid survey was begun in 1973 in order to study those asteroids which may intersect the orbits of the inner planets. Throughout the history of the survey, many of the various classes of asteroids were investigated. The near-Earth objects including the Apollo, Amor, and Aten families were studied in addition to asteroids whose orbits cross that of Mars, and some objects which are generally confined to the main belt. Observing was done on the 18 inch Schmidt telescope at the Palomar Mtn. Observatory. Typically, two consecutive photographs of a favorable field are taken. The exposure times of the films are usually twenty minutes and ten minutes, respectively. The telescope is guided at sidereal rate, so that asteroids will leave short trailed images. The films are then scanned for trails. By comparing the two films, the direction and approximate rate of motion of an asteroid may be determined.

  14. Security for a Smarter Planet

    NASA Astrophysics Data System (ADS)

    Nagaratnam, Nataraj

    Bit by bit, our planet is getting smarter. By this, we mean the systems that run, the way we live and work as a society. Three things have brought this about - the world is becoming instrumented, interconnected and intelligent. Given the planet is becoming instrumented and interconnected, this opens up more risks that need to be managed. Escalating security and privacy concerns along with a renewed focus on organizational oversight are driving governance, risk management and compliance (GRC) to the forefront of the business. Compliance regulations have increasingly played a larger role by attempting to establish processes and controls that mitigate the internal and external risks organizations have today. To effectively meet the requirements of GRC, companies must prove that they have strong and consistent controls over who has access to critical applications and data.

  15. Interiors of the giant planets

    NASA Technical Reports Server (NTRS)

    Hubbard, W. B.

    1986-01-01

    The interior structure of the Jovian planets was studied by means of observational data obtained by ground-based astronomy. Recent work was oriented toward a determination of oblateness from occultation measurements of the shape of planetary atmospheres. This provides a determination of the degree of central condensation of the planet, which is then compared with interior models and theoretical equations of state. As a serendipitous result of the attempts to measure the oblateness of Neptune, a partial Neptune ring (or arc) was discovered following an occultation observation on July 22, 1984. During 1985, older observations were reexamined to determine whether Neptune arcs had been detected (but not identified) during previous occultations. It appears that Neptunian arcs may locally imitate Uranian rings, with an 1981 event resembling Uranus' epsilon ring, while an 1984 event was more similar to the thinner Uranian rings such as the alpha ring.

  16. Artemis: A Stratospheric Planet Finder

    NASA Technical Reports Server (NTRS)

    Ford, H. C.; Petro, L. D.; Burrows, C.; Ftaclas, C.; Roggemann, M. C.; Trauger, J. T.

    2003-01-01

    The near-space environment of the stratosphere is far superior to terrestrial sites for optical and infrared observations. New balloon technologies will enable flights and safe recovery of 2-ton payloads at altitudes of 35 km for 100 days and longer. The combination of long flights and superb observing conditions make it possible to undertake science programs that otherwise could only be done from orbit. We propose to fly an "Ultra-Hubble" Stratospheric Telescope (UHST) equipped with a coronagraphic camera and active optics at 35 km to search for planets around 200 of the nearest stars. This ULDB mission will establish the frequency of solar-type planetary systems, and provide targets to search for earth-like planets.

  17. COROT: asteroseismology and planet finding

    NASA Astrophysics Data System (ADS)

    Baglin, A.; Auvergne, M.; Barge, P.; Buey, J.-T.; Catala, C.; Michel, E.; Weiss, W.; COROT Team

    2002-01-01

    The COROT project, developed in the framework of the CNES small satellite program with a wide European cooperation, will be launched in 2004. It is dedicated to seismology and detection of telluric planets. It will perform relative broad band photometry in visible light, during very long (150 days) observing runs in the same direction. Both programs are working simultaneously on the same region of the sky. The seismology program aims at mapping the H-R diagram and study in details approximately 50 targets brighter than 9th magnitude. Another 50 will also be observed with a lower accuracy. The exoplanet program will search for telluric planets slightly larger than the Earth, in the habitable zone and closer.

  18. Studying planet populations by gravitational microlensing

    NASA Astrophysics Data System (ADS)

    Dominik, Martin

    2010-09-01

    The ‘most curious’ effect of the bending of light by the gravity of stars has evolved into a successful technique unlike any other for studying planets within the Milky Way and even other galaxies. With a sensitivity to cool planets around low-mass stars even below the mass of Earth, gravitational microlensing fits in between other planet search techniques to form a complete picture of planet parameter space, which is required to understand their origin in general, that of habitable planets more particularly, and that of planet Earth especially. Current campaigns need to evolve from first detections to obtaining a sample with well-understood selection bias that allows to draw firm conclusions about the planet populations. With planetary signals being a transient phenomenon, gravitational microlensing is a driver for new technologies in scheduling and management of non-proprietary heterogeneous telescope networks, and can serve to demonstrate forefront science live to the general public.

  19. Astrometeric Science with SIM PlanetQuest

    NASA Technical Reports Server (NTRS)

    Shao, Michael; Unwin, Stephen

    2006-01-01

    This viewgraph presentation reviews Astrometry with the Space Interferometry Mission (SIM) PlanetQuest. The topics include: 1) SIM PlanetQuest - the World's First Long- Baseline Optical Interferometer in Space; 2) National Academy of Sciences / NRC endorses SIM PlanetQuest; 3) SIM Planet Search; 4) Planetary System Architectures & Diversity; 5) SIM Search for 110 M(sub Earth) Planets Around Nearby Stars; 6) Deep Search of 120 nearby stars; 7) Planets around Young Stars; 8) SIM PlanetQuest Science Team; 9) Dark Halo of our Galaxy; 10) Dynamics of Galaxy Groups within 5 Mpc; 11) Probing Active Galactic Nuclei with Astrometry; 12) Snapshot Observing Mode: Astrometry for the masses; 13) SIM Technology Development is Complete; and 14) SIM Hardware, Tested for Flight.

  20. A THIRD GIANT PLANET ORBITING HIP 14810

    SciTech Connect

    Wright, J. T.; Fischer, D. A.; Ford, Eric B.; Veras, D.; Wang, J.; Henry, G. W.; Marcy, G. W.; Howard, A. W.; Johnson, John Asher

    2009-07-10

    We present new precision radial velocities and a three-planet Keplerian orbit fit for the V = 8.5, G5 V star HIP 14810. We began observing this star at Keck Observatory as part of the N2K Planet Search Project. Wright et al. announced the inner two planets to this system, and subsequent observations have revealed the outer planet and the proper orbital solution for the middle planet. The planets have minimum masses of 3.9, 1.3, and 0.6 M {sub Jup} and orbital periods of 6.67, 147.7, and 952 day, respectively. We have numerically integrated the family of orbital solutions consistent with the data and find that they are stable for at least 10{sup 6} yr. Our photometric search shows that the inner planet does not transit.