bluuebunny/crossref_metadata_2025_split huggingface dataset:
Astronomy from the Antarctic Plateau: a global personal vision
Authors: Zinnecker Hans 
Published: October 2010

AbstractThe Antarctic Plateau (Dome C, also Dome A) is emerging as an especially good sitefor astronomical observations (high, dry, cold, no wind, good free seeing above a certainboundary layer). Over the last few years, several meetings and conferences tookplace to discuss potential astrophysical science cases for such exceptional atmosphericconditions. I summarise my personal conclusions from these discussions and presenta global vision (roadmap) for Antarctic Astronomy for future optical, near-IR, thermal-IR, andfar-IR/sub-mm observations. The need for international collaboration between Europe, Australia and China is stressed.
Challenges in Astronomy Education
Authors: De Greve Jean-Pierre 
Published: October 2010

AbstractAstronomy is an attractive subject for education. It deals with fascination of the unknown and the unreachable, yet is uses tools, concepts and insights from various fundamental sciences such as mathematics, physics, chemistry, biology. Because of this it can be well used for introducing sciences to young people and to raise their interest in further studies in that direction. It is also an interesting subject for teaching as its different aspects (observation techniques, theory, data sampling and analysis, modelling,?) offer various didactical approaches towards different levels of pupils, students and different backgrounds. And it gives great opportunities to teach and demonstrate the essence of scientific research, through tutorials and projects. In this paper we discuss some of the challenges education in general, and astronomy in particular, faces in the coming decades, given the major geophysical and technological changes that can be deducted from our present knowledge. This defines a general, but very important background in terms of educational needs at various levels, and in geographical distribution of future efforts of the astronomical community. Special emphasis will be given to creative approaches to teaching, to strategies that are successful (such as the use of tutorials with element from computer games), and to initiatives complementary to the regular educational system. The programs developed by the IAU will be briefly highlighted.
Europa, Enceladus, and Titan as possible sites for life
Authors: Courtin Régis 
Published: October 2010

AbstractDespite quite distinct bulk properties, Europa, the third largest Jovian satellite (d=3138 km), and the Saturnian satellites Enceladus (d~500 km) and Titan (d=5151 km) share a remarkable common feature which is a strong indication of the presence of liquid water at some level below the surface. The possibilities for the development of life organisms on these bodies are reviewed.
Gas-phase prebiotic chemistry in extraterrestrial environments
Authors: Balucani Nadia 
Published: October 2010

AbstractA variety of molecular species up to complex polyatomic molecules/radicals have been identified in many extraterrestrial gaseous environments, including interstellar clouds, cometary comae and planetary atmospheres. Amongst the identified molecules/radicals, a large percentage are organic in nature and encompass also prebiotic molecules. Different types of microscopic processes are believed to be involved in their formation, including surface processes, ion- and radical- molecule reactions. A thorough characterization of such a complex chemistry relies on a multi-disciplinary approach, where the observations are complemented by accurate chemical modeling. Unfortunately, a literature survey reveals that only a small percentage of the elementary reactions considered in the available models have been characterized in laboratory experiments. In this contribution, a brief overview will be given of recent experimental techniques that have allowed us to reach a better description of neutral-neutral gas-phase reactions, which might be responsible for the formation of simple prebiotic molecules.
Surviving on Mars: test with LISA simulator
Authors: Galletta Giuseppe , D'Alessandro Maurizio , Bertoloni G. , Castellani F. 
Published: October 2010

AbstractWe present the results of experiments performed in the Padua simulators of planetary environments, named LISA, used to study the limits of bacterial life on the planet Mars. The survival of Bacillus strains for some hours in Martian environment is briefly discussed.
High cadence near-infrared transit timing observations of extrasolar planets
Authors: Cáceres Claudio , Ivanov Valentin D. , ~Minniti Dante , Naef Dominique , Melo Claudio , Mason Elena , Selman Fernando , Pietrzynsky Grzegorz 
Published: October 2010

AbstractCurrently the only technique sensitive to Earth mass planets around nearby stars (that are too close for microlensing) is the monitoring of the transit time variations of the transiting extrasolar planets. We search for additional planets in the systems of the hot-Neptune GJ-436 b, and the hot-Jupiter XO-1 b, using high cadence observations in the J and KS bands, with the SofI and ISAAC instruments from La Silla Paranal Observatory. New high-precision transit timing measurements were used to derive new ephemeris. No statistically significant timing deviations were detected. We demonstrate that the high cadence ground based near-infrared observations are successful in constraining the mean transit time to 30 sec, and are a viable alternative to space missions.
Orbital stability of Earth-type planets in stellar binary systems
Authors: Eberle Jason , Cuntz Manfred , Musielak Zdzislaw E. 
Published: October 2010

AbstractAn important factor in estimating the likelihood of life elsewhere in the Universe is determining the stability of a planet's orbit. A significant fraction of stars like the Sun occur in binary systems which often has a considerable effect on the stability of any planets in such a system. In an effort to determine the stability of planets in binary star systems, we conducted a numerical simulation survey of several mass ratios and initial conditions. We then estimated the stability of the planetary orbit using a method that utilizes the hodograph to determine the effective eccentricity of the planetary orbit. We found that this method can serve as an orbital stability criterion for the planet.
Defining the envelope for the search for life in the Universe
Authors: Rothschild Lynn J. 
Published: October 2010

AbstractThe search for life in the universe relies on defining the limits for life and finding suitable conditions for its origin and evolution elsewhere. From the biological perspective, a conservative approach uses life on earth to set constraints on the environments in which life can live. Conditions for the origin of life, even on earth, cannot yet be defined with certainty. Thus, we will describe what is known about conditions for the origin of life and limits to life on earth as a template for life elsewhere, with a particular emphasis on such physical and chemical parameters as temperature, pH, salinity, desiccation and radiation. But, other life forms could exist, thus extending the theoretical possibility for life elsewhere. Yet, this potential is not limitless, and so constraints for life in the universe will be suggested.
Earthshine observations and the detection of vegetation on extrasolar planets
Authors: Briot Danielle 
Published: October 2010

AbstractTo prepare future observations of terrestrial planets and the detection of life, we search for life on the planet Earth seen as a point source. Observations of Earthshine is a convenient way to see Earth as a remote planet. The vegetation reflectance spectrum presents a sharp edge in the near infrared: the Vegetation Red Edge. Observational programs in progress are described, particularly our observations at the Concordia station in Antarctica.
Interior structure models of terrestrial exoplanets and application to CoRoT-7 b
Authors: Wagner Frank W. , Sohl Frank , Rauer Heike , Hussmann Hauke , Grott Matthias 
Published: October 2010

AbstractIn this study, we model the internal structure of CoRoT-7b, considered as a typical extrasolar terrestrial planet, using mass and energy balance constraints. Our results suggest that the deep interior is predominantly composed of dry silicate rock, similar to the Earth's Moon. A central iron core, if present, would be relatively small and less massive (<15 wt.% of the planet's total mass) as compared to the Earth's (core mass fraction 32.6 wt.%). Furthermore, a partly molten near-surface magma ocean could be maintained, provided surface temperatures were high enough and the rock component mainly composed of Earth-like mineral phase assemblages.
Mars Science Laboratory (MSL) and the future missions to Mars
Authors: Cabane Michel ,   the SAM Team
Published: October 2010

AbstractAfter their formation, and for almost 0.5 Gyr, Mars and Earth evolved in the same manner. On Earth, life occured very early, around 3.6 Gy ago. Then, the hypothesis that life might have occured also on Mars, and be extinct, is not unrealistic. If this is true, then complex molecules could be present, representing an early state of life-building blocks. Missions to Mars (Viking 1-2, Phoenix) have carried instruments capable to search for molecular indicators, although up to now, no positive detection has been obtained. Future missions to Mars (MSL-NASA, Exomars-ESA) will use enhanced experiments to try to end this quest.
Characteristics of the Kepler target stars
Authors: Batalha Natalie M. , Borucki William J. , Koch David G. , Brown Timothy M. , Caldwell Douglas A. , Latham David W. 
Published: October 2010

AbstractThe Kepler Mission successfully launched March 6, 2009, beginning its 3.5-year mission to determine the frequency of Earth-size planets in the habitable zones of late-type stars. The brightnesses of over 100,000 stars are currently being monitored for transit events with an expected differential photometric precision of 20 ppm at V=12 for a 6.5-hour transit. The same targets will be observed continuously over the mission duration in order to broaden the detection space to orbital periods comparable to that of Earth. This paper provides an overview of the selection and prioritization criteria used to choose the stars that Kepler is observing from the > 4.5 million objects in the 100 square degree field of view. The characteristics of the Kepler targets are described as well as the implications for detectability of planets in the habitable zone smaller than 2R⊕.
SIM Lite astrometric observatory for detection of Earth-like planets
Authors: Pan Xiaopei , Shao Michael , Goullioud Renaud 
Published: October 2010

AbstractThe SIM Lite Astrometric Observatory is an optical astrometry mission for detection of Earth-like planets and investigation of dark matter, galaxy assembly, black holes etc. SIM Lite is a minimum system that performs the full NRC recommenced SIM science programs. This paper summarize the latest status and progresse of the SIM Lite space mission.
Gavriil Adrianovich Tikhov (1875-1960) a pioneer in astrobiology
Authors: Tejfel Victor 
Published: October 2010

AbstractAstrobiology emerged as a scientific discipline in Kazakhstan more than half-a-century ago and flourished for many years under the leadership of Gavriil A. Tikhov, the oldest Pulkovian astrophysicist, member of the Academy of Sciences of the KazSSR (ASKSSR), and corresponding member of the Academy of Sciences of the USSR.
George W. Wetherill (1925-2006): physicist, geochemist, planetary scientist, astrobiologist
Authors: Boss Alan P. 
Published: October 2010

AbstractTrained as a physicist, George W. Wetherill (1925-2006) made seminal contributions to the fields of geochemical dating, meteoritical and asteroidal science, and the theory of the formation of terrestrial planets, evolving along the way into one of the first astrobiologists.
Brown Dwarf Model Atmospheres Based on Multi-Dimensional Radiation Hydrodynamics
Authors: Allard France , Freytag Bernd 
Published: October 2010

AbstractThe atmospheres of Brown Dwarfs (BDs) are the site of molecular opacities and cloud formation, and control their cooling rate, radius and brightness evolution. Brown dwarfs evolve from stellar-like properties (magnetic activity, spots, flares, mass loss) to planet-like properties (electron degeneracy of the interior, cloud formation, dynamical molecular transport) while retaining, due to their fully convective interior, larger rotational velocities (≤ 30 km/s i.e. P < 4 hrs versus 11 hrs for Jupiter). Model atmospheres treating all this complexity are therefore essential to understand the evolution properties, and to interpret the observations of these objects. While the pure gas-phase based NextGen model atmospheres (Allard et al. 1997, Hauschildt et al. 1999) have allowed the understanding of the several populations of Very Low Mass Stars (VLMs), the AMES-Dusty models (Allard et al. 2001) based on equilibrium chemistry have reproduced some near-IR photometric properties of M and L-type brown dwarfs, and played a key role in the determination of the mass of brown dwarfs and Planetary Mass Objects (PMOs) in the eld and in young stellar clusters. In this paper, we present a new model atmosphere grid for VLMs, BDs, PMOs named BT-Settl, which includes a cloud model and dynamical molecular transport based on mixing information from 2D Radiation Hydrodynamic (RHD) simulations (Freytag et al. 2009). We also present the status of our 3D RHD simulations including rotation (Coriolis forces) of a cube on the surface of a brown dwarf. The BT-Settl model atmosphere grid will be available shortly via the Phoenix web simulator (http://phoenix.ens-lyon.fr/simulator/).
Testing Models with Brown Dwarf Binaries
Authors: Dupuy Trent J. , Liu Michael C. 
Published: October 2010

AbstractWe have been using Keck laser guide star adaptive optics to monitor the orbits of ultracool binaries, providing dynamical masses at lower luminosities and temperatures than previously available and enabling strong tests of theoretical models. (1) We find that model color–magnitude diagrams cannot reliably be used to infer masses as they do not accurately reproduce the colors of ultracool dwarfs of known mass. (2) Effective temperatures inferred from evolutionary model radii can be inconsistent with temperatures derived from fitting observed spectra with atmospheric models by at most 100–300 K. (3) For the single pair of field brown dwarfs with a precise mass (3%)andage determination (≈25%), the measured luminosities are ~2–3× higher than predicted by model cooling rates (masses inferred fromLboland age are 20–30% larger than measured). Finally, as the sample of binaries with measured orbits grows, novel tests of brown dwarf formation theories are made possible (e.g., testing theoretical eccentricity distributions).
Mid-Infrared Variability in Binary Brown Dwarfs
Authors: Sterzik Michael F. , Chauvin Gael , Geißler Kerstin , Pantin Eric 
Published: October 2010

AbstractWe have spatially resolved several nearby binary brown dwarfs and obtained mid-infrared photometry with VISIR at the VLT. In particular, we have monitored ε Indi B and HD 130948 in several narrow-band MIR filters. The 10.5μm band is a probe to constrain non-equilibrium chemistry in the atmosphere of cool brown dwarfs.
CORNISH: A 5 GHz VLA survey of the Galactic plane
Authors: Purcell Cormac R. , Hoare Melvin G. ,   the CORNISH team
Published: October 2010

AbstractThe CORNISH (Co-Ordinated Radio ‘N’ Infrared Survey for High-mass star formation) project is the radio continuum part of a series of multi-wavelength surveys of the Galactic Plane that focus on the northern GLIMPSE-I region (10° < l <65°, |b| < 1°) observed by the SPITZER satellite in the mid-infrared (Churchwell et al. 2009). CORNISH has delivered a complementary 5 GHz arcsecond resolution, radio-continuum survey to address key questions in high-mass star formation as well as many other areas of astrophysics.
High spatial resolution Galactic 3D extinction mapping with IPHAS
Authors: Sale S. E. , Drew J. E. ,   the IPHAS Collaboration
Published: October 2010

AbstractAn algorithm, MEAD, is presented, which can map extinction in three dimensions, with fine distance and angular resolutions. MEAD is then employed when studying the structure of the outer Galaxy. We show that the Galaxy's radial density profile takes the form of a broken exponential, with density dropping off more steeply beyond a Galacto-centric radius of ~13 kpc.
I-GALFA: The Inner-Galaxy ALFA Low-Latitude H I Survey
Authors: Koo Bon-Chul , Gibson Steven J. , Kang Ji-hyun , Douglas Kevin A. , Park Geumsook , Peek Joshua E. G. , Korpela Eric J. , Heiles Carl E. , Bania Thomas M. 
Published: October 2010

AbstractThe I-GALFA survey is mapping HI 21 cm emission in the inner parts of our Milky Way Galaxy using the Arecibo L-band Feed Array (ALFA). Examples of various H i features such as supershells and chimneys are shown.
Abundance structure and chemical evolution of the Galactic disc
Authors: Bensby Thomas , Feltzing Sofia 
Published: October 2010

AbstractWe have obtained high-resolution, high signal-to-noise spectra for 899 F and G dwarf stars in the Solar neighbourhood. The stars were selected on the basis of their kinematic properties to trace the thin and thick discs, the Hercules stream, and the metal-rich stellar halo. A significant number of stars with kinematic properties ‘in between’ the thin and thick discs were also observed to investigate in greater detail the dichotomy of the Galactic disc. All stars have been homogeneously analysed, using the exact same methods, atomic data, model atmospheres, etc., and also truly differentially to the Sun. Hence, the sample is likely to be free from internal errors, allowing us to, in a multi-dimensional space consisting of detailed elemental abundances, stellar ages, and the full three-dimensional space velocities, reveal very small differences between the stellar populations.
Abundance gradients: tracing the chemical properties of the disk
Authors: Costa Roberto D.D. , Maciel Walter J. 
Published: October 2010

AbstractAbundance gradients are key parameters to constrain the chemical evolution of the galactic disk. In this review recent determinations for the radial gradient are described, including its slope as derived from different objects such as planetary nebulae, HII regions, cepheids, or B stars, and for different elements. Inner and outer limits for the radial gradient, as well as its time evolution, both related to the chemical evolution of the Galaxy, are also described. The possible existence of azimuthal and vertical gradients is also discussed.
Physics and Structure of the Galactic disc(s)
Authors: Schönrich Ralph A. 
Published: October 2010

AbstractThe combination of classical models of chemical evolution with radial mixing and dynamics of the Galactic disc has opened alternative methods of understanding the detailed structure of the solar neighbourhood. I will show how radial mixing alters the views on chemical evolution as demonstrated by Schönrich & Binney (2009). I will explain how the model gives rise to a very natural division of the Galactic disc into a thick and a thin component, which can be examined in the light of detailed observational studies combining information on kinematics, chemistry and stellar ages.
A New Comprehensive Catalogue of Infrared Dark Clouds
Authors: Fuller G. A. , Peretto N. 
Published: October 2010

AbstractTo better characterise infrared dark clouds (IRDCs), and the star formation within them, a comprehensive catalogue of IRDCs has been constructed from the Spitzer GLIMPSE and MIPSGAL archival data. Mosaicing the individual survey blocks together, we have used a new extraction method to identify dark clouds up to 30′ in size, and produce a column density image of each cloud. In total the catalogue contains over 11,000 clouds, defined as connected regions with 8 micron optical depth > 0.35 (corresponding to column densities < 1022cm−2). The extraction algorithm also identifies sub-structures (fragments) within each cloud. These Spitzer dark clouds (SDCs) range in mass from 10M⊙to 104M⊙. About 80% of the SDCs were previously unidentified. Only ~ 30% of the SDCs are associated with 24μm point-like sources, leaving the majority of these clouds with no apparent sign of star formation activity. This new catalogue provides an important new resource for future studies of the initial conditions of star formation in the Galaxy.
The JCMT Legacy Survey: Mapping the Milky Way in the Submillimetre
Authors: Chrysostomou Antonio ,   the members of the JLS teams
Published: October 2010

AbstractThe JCMT Legacy Survey (JLS) is an ambitious programme of independent surveys to study our Galaxy and universe in the submillimetre (λ = 450 − 850 μm) from the summit of Mauna Kea, Hawaii. With its scientific breadth and unique spectral window, it is clear that the JLS will have a significant impact on star formation studies in the near future and beyond. Its complementarity with other surveys (e.g. Spitzer, Herschel) will make the JLS a very valuable resource for multi-wavelength studies for low and high-mass star formation across the Milky Way. The JLS is currently in its second year of operation.
The Galactic star formation rate as seen by the Spitzer Space Telescope
Authors: Robitaille Thomas P. , Whitney Barbara A. 
Published: October 2010

AbstractWe present preliminary results of a study to determine the star formation rate of the Galaxy using a census of young stellar objects (YSOs) in the Spitzer/GLIMPSE and MIPSGAL surveys, which cover nearly 300 square degrees of the Galactic mid-plane. We find a value of 1.7 M⊙/yr, consistent with independent estimates.
The Red MSX Source Survey - Massive Star Formation in the Milky Way
Authors: Lumsden Stuart , Hoare Melvin , Davis Ben ,   the RMS team
Published: October 2010

AbstractWe present the results of a Galaxy-wide survey for young massive stars still in the process of formation. Our data are consistent with a model in which the stars form through accretion disks with the overall Galactic star formation rate being 3 M⊙ per year.
Star Formation Histories from Pan-Chromatic Infrared Continuum Surveys
Authors: Molinari Sergio 
Published: October 2010

AbstractOne of the currently most disputed issues in Star Formation is the timeline of the whole process. Is it a “slow” process of cloud assembly which, mediated by magnetic fields, evolve toward turbulence-supported clumps which are eventually super-critical to collapse, e.g. McKee & Tan (2003)? Or do clumps originate in already super-critical state in the post-shock regions of large-scale Galactic converging flows, e.g. Hartmann et al. (2001) with a rapid collapse in a crossing time or so (Elmegreen 2000)?A pan-chromatic 1μm-1mm continuum view of cluster forming regions in their early stages offers access to the most massive members longward of 5-10μm, as well as the low-mass members which instead dominate the emission in the near-IR, offering an interesting potential in stimulating advances in theoretical modelling of clustered star formation, its history and rate.
The population of Planetary Nebulae in the Milky Way
Authors: Corradi Romano L. M. 
Published: October 2010

AbstractExtensive surveys of the Milky Way have provided a global view of the population of planetary nebulae in the Milky Way. Their chemical, dynamical, and morphological properties, the link with their red giant progenitors and white dwarf descendants, and the implications on our understanding of the chemical evolution of the Galaxy, are discussed.
The H.E.S.S. Galactic Plane Survey
Authors: de Oña-Wilhelmi Emma 
Published: October 2010

AbstractThe H.E.S.S. Galactic Plane Survey (GPS) has revealed a large number of Galactic Sources, including Pulsar Wind Nebulae (PWN), Supernova Remnants (SNRs), giant molecular clouds, star formation regions and compact binary systems, as well as a number of unidentified objects, or dark sources, for which no obvious counterparts at other wavelengths have yet been found. We will review the latest results from the GPS observations and discuss the most interesting cases.