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Sep 3, 2021
09/21
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International Astronomical Union. Symposium (206th : 2001 : Rio de Janeiro, Brazil)
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xviii, 531 p. : 25 cm
Topics: Astronomical masers -- Congresses, Protostars -- Congresses, Black holes (Astronomy) -- Congresses
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Jun 12, 2011
06/11
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Finarelli, Margaret G
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Electric propulsion, whether powered by solar generators or by nuclear reactors, offers a valuable solution to the problems posed by chemical in-space propulsion. It maybe argued that solar electric propulsion is more applicable to near-Earth missions or to missions to the nearer planets, whereas nuclear electric propulsion remains operational even in the vicinity of the far outer planets. Taking into account considerations such as cost and safety it can be concluded that both types of electric...
Topics: ASTRONOMY, INFRARED RADIATION, STAR FORMATION, STELLAR ENVELOPES, CAMERAS, PHOTOSPHERE, PIXELS,...
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xx, 1293 p. : 24 cm
Topics: Protostars -- Congresses, Planets -- Origin -- Congresses, Cosmochemistry -- Congresses, Solar...
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211
May 23, 2011
05/11
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Lingle, Craig S.; Brenner, Anita C.; Zwally, H. Jay; DiMarzio, John P
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Mean changes in the surface elevation near the west margin of the Greenland ice sheet are measured using Seasat altimetry and altimetry from the Geosat Exact Repeat Mission (ERM). The Seasat data extend from early July through early October 1978. The ERM data extend from winter 1986-87 through fall 1988. Both seasonal and multi-year changes are measured using altimetry referenced to GEM T2 orbits. The possible effects of orbit error are minimized by adjusting the orbits into a common ocean...
Topics: ABSORPTION SPECTRA, CARBONYL COMPOUNDS, METHYL ALCOHOL, PROTOSTARS, MIE SCATTERING, SULFIDES,...
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May 30, 2011
05/11
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Caimi, Raoul E.; Margashayam, Ravi N.; Nayfeh, Jamal F
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Rocket-induced vibration and ignition overpressure response environments are predicted in the low-frequency (5 to 200 hertz) range. The predictions are necessary to evaluate their impact on critical components, structures, and facilities in the immediate vicinity of the rocket launch pad.
Topics: ASTROPHYSICS, PLANETARY EVOLUTION, PROTOPLANETARY DISKS, PROTOSTARS, GAS GIANT PLANETS, CIRCULAR...
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May 27, 2011
05/11
by
NON
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The purpose of the workshop was to understand what effect circumstellar dust clouds will have on NASA's proposed Terrestrial Planet Finder (TPF) mission's ability to search for terrestrial-sized planets orbiting stars in the solar neighborhood. The workshop participants reviewed the properties of TPF, summarized what is known about the local zodiacal cloud and about exozodiacal clouds, and determined what additional knowledge must be obtained to help design TPF for maximum effectiveness within...
Topics: T TAURI STARS, ICE, MOLECULES, ABSORPTION SPECTRA, ICE NUCLEI, MOLECULAR CLOUDS, SOLAR SYSTEM,...
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329
May 22, 2011
05/11
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Han, Daesoo; Kim, Young S.; Noz, Marilyn E
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It is shown that the system of two coupled harmonic oscillators shares the basic symmetry properties with the covariant harmonic oscillator formalism which provides a concise description of the basic features of relativistic hadronic features observed in high-energy laboratories. It is shown also that the coupled oscillator system has the SL(4,r) symmetry in classical mechanics, while the present formulation of quantum mechanics can accommodate only the Sp(4,r) portion of the SL(4,r) symmetry....
Topics: EMBEDDING, PROTOSTARS, INFRARED ASTRONOMY SATELLITE, MASS, MOLECULAR CLOUDS, STAR CLUSTERS, STAR...
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317
May 24, 2011
05/11
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Palosz, W.; George, M. A.; Collins, E. E.; Chen, K.-T.; Zhang, Y.; Burger, A
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Crystals of Cd(1-x)Zn(x)Te with x = 0.2 and 40 g in weight were grown on monocrystalline cadmium-zinc telluride seeds by closed-ampoule physical vapor transport with or without excess (Cd Zn) in the vapor phase. Two post-growth cool-down rates were used. The crystals were characterized using low temperature photoluminescence, atomic force microscopy, chemical etching, X-ray diffraction and electrical measurements. No formation of a second, ZnTe-rich phase was observed.
Topics: PROTOSTARS, COLLAPSE, MOLECULAR CLOUDS, FAR INFRARED RADIATION, LINE SPECTRA, STELLAR MASS, STELLAR...
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Jun 2, 2011
06/11
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Brat, Guillaume; Havelund, Klaus; Park, SeungJoon; Visser, Wille
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Software, particularly systems capable of autonomous operation, is fast becoming a major enabling technology at NASA. Unfortunately, the cost savings of autonomous software systems can easily be offset by the risk of in-flight failure of the software. Although rigorous testing of software before deployment can increase the confidence of its correctness, the tendency of in-flight software to be multi-threaded makes it hard to find subtle errors caused by the unforeseen interaction of...
Topics: INTERSTELLAR MATTER, LINE OF SIGHT, NITRILES, CYANIDES, BIOLOGICAL EVOLUTION, ORGANIC MATERIALS,...
Isotopically fractionated material is found in many solar system objects, including meteorites and comets. It is thought, in some cases, to trace interstellar material that was incorporated into the solar system without undergoing significant processing. Here, we show the results of models and observations of the nitrogen and carbon fractionation in proto-stellar cores.
Topics: NASA Technical Reports Server (NTRS), FRACTIONATION, ISOTOPES, PROTOSTARS, CARBON, NITROGEN, RADIO...
The nonaxisymmetric stability of self-gravitating, geometrically thick accretion disks has been studied for protostellar systems having a wide range of disk-to-central object mass ratios. Global eigenmodes with four distinctly different characters were identified using numerical, nonlinear hydrodynamic techniques. The mode that appears most likely to arise in normal star formation settings, however, resembles the 'eccentric instability' that was identified earlier in thin, nearly Keplerian...
Topics: NASA Technical Reports Server (NTRS), ACCRETION DISKS, MASS RATIOS, PROTOSTARS, STABILITY, STAR...
The proposal achieved many of its objectives. The main area of investigation was the interaction of young planets with surrounding protostellar disks. The grant funds were used to support visits by CoIs and visitors: Gordon Ogilvie, Gennaro D Angelo, and Matthew Bate. Funds were used for travel and partial salary support for Lubow. We made important progress in two areas described in the original proposal: secular resonances (Section 3) and nonlinear waves in three dimensions (Section 5). In...
Topics: NASA Technical Reports Server (NTRS), ACCRETION DISKS, PROTOSTARS, PLANETARY EVOLUTION,...
Anomalously fractionated isotopic material is found in many primitive Solar System objects, such as meteorites and comets. It is thought, in some cases, to trace interstellar matter that was incorporated into the Solar Nebula without undergoing significant processing. We will present the results of models of the nitrogen, oxygen, and carbon fractionation chemistry in dense molecular clouds, particularly in cores where substantial freeze-out of molecules on to dust has occurred. The range of...
Topics: NASA Technical Reports Server (NTRS), INTERSTELLAR MATTER, FRACTIONATION, ISOTOPES, METEORITIC...
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269
May 23, 2011
05/11
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Kavaya, Michael J.; Spiers, Gary D.; Lobl, Elena S.; Rothermel, Jeff; Keller, Vernon W
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Innovative designs of a space-based laser remote sensing 'wind machine' are presented. These designs seek compatibility with the traditionally conflicting constraints of high scientific value and low total mission cost. Mission cost is reduced by moving to smaller, lighter, more off-the-shelf instrument designs which can be accommodated on smaller launch vehicles.
Topics: MIE SCATTERING, INFRARED RADIATION, PROTOSTARS, ABSORPTION SPECTRA, CARBONYL COMPOUNDS, INFRARED...
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.
Topics: NASA Technical Reports Server (NTRS), ACCRETION DISKS, BINARY STARS, PLANETS, PLANETARY EVOLUTION,...
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.
Topics: NASA Technical Reports Server (NTRS), ASTROPHYSICS, PLANETARY EVOLUTION, PROTOPLANETARY DISKS,...
Very little work has been carried out to determine whether or not large organic molecules similar to those observed on the surfaces of minor solar system bodies also reside in the mantles of icy grains located in dense molecular clouds or in the local environments of protostars and PNIS stars. Ten years ago Lacy et al. first identified a broad absorption band near 4.62 micron, the C equivalent N stretch fundamental, in the spectra of two embedded protostars, W33A and NGC 7538 IRS 9. The only...
Topics: NASA Technical Reports Server (NTRS), T TAURI STARS, ICE, MOLECULES, ABSORPTION SPECTRA, ICE...
This study constitutes one part of our multi-disciplinary approach to the evolution of planet-forming disks. The goal is to establish the disks' thermal and mechanical properties as they grow by the infall of their parent interstellar clouds. Thus far, significant advances toward establishing the evolving surface density of such disks was made.
Topics: NASA Technical Reports Server (NTRS), ACCRETION DISKS, CHEMICAL EVOLUTION, PROTOSTARS, STELLAR...
The research concentrated on high angular resolution (arc-second scale) studies of molecular cloud cores associated with very young star formation. New ways to study disks and protoplanetary systems were explored. Findings from the areas studied are briefly summarized: (1) molecular clouds; (2) gravitational contraction; (3) jets, winds, and outflows; (4) Circumstellar Disks (5) Extrasolar Planetary Systems. A bibliography of publications and submitted papers produced during the grant period is...
Topics: NASA Technical Reports Server (NTRS), MOLECULAR CLOUDS, PROTOSTARS, STAR FORMATION, ACCRETION...
IRAS l6253-2429. the source of the Wasp-Waist Nebula seen in Spitzer IRAC images, is an isolated very low luminosity ("VeLLO") Class 0 protostar in the nearby rho Ophiuchi cloud. We present VLA ammonia mapping observations of the dense gas envelope feeding the central core accreting system. We find a flattened envelope perpendicular to the outflow axis, and gas cavities that appear to cradle the outflow lobes as though carved out by the flow and associated (apparently precessing) jet....
Topics: NASA Technical Reports Server (NTRS), AMMONIA, INFRARED ASTRONOMY SATELLITE, MASS, OPHIUCHI CLOUDS,...
The principal issues are addressed: the fragmentation of molecular clouds into units of stellar mass and the impact of star formation on molecular clouds. The observational evidence for fragmentation is summarized, and the gravitational instability described of a uniform spherical cloud collapsing from rest. The implications are considered of a finite pressure for the minimum fragment mass that is attainable in opacity-limited fragmentation. The role of magnetic fields is discussed in resolving...
Topics: NASA Technical Reports Server (NTRS), FRAGMENTATION, MOLECULAR CLOUDS, STELLAR EVOLUTION, STELLAR...
Anomalously fractionated isotopic material is found in many primitive Solar System objects, such as meteorites and comets. It is thought, in some cases, to trace interstellar matter that was incorporated into the Solar Nebula without undergoing significant processing. We will present the results of models of the nitrogen, oxygen, and carbon fractionation chemistry in dense molecular clouds, particularly in cores where substantial freeze-out of molecules on to dust has occurred. The range of...
Topics: NASA Technical Reports Server (NTRS), FRACTIONATION, INTERSTELLAR MATTER, ISOTOPES, MOLECULAR...
Isotopically fractionated material is found in many solar system objects, including meteorites and comets. It is considered, in some cases, to trace interstellar material that was incorporated into the solar system without undergoing significant processing, thus preserving the fractionation. In interstellar molecular clouds, ion-molecule chemistry continually cycles nitrogen between the two main reservoirs - N and N2 - leading to only minor N-15 enrichments. Charnley and Rodgers showed that...
Topics: NASA Technical Reports Server (NTRS), CHEMICAL FRACTIONATION, INTERSTELLAR MATTER, PROTOSTARS,...
I will present an overview of the current paradigm for the theory of gaseous accretion disks around young stars. Protostellar disks form from the collapse of rotating molecular cloud cores. The disks evolve via outward angular momentum transport provided by several mechanisms: gravitational instabilities, thermal convective turbulence, and magnetic stresses. I will review the conditions under which these mechanisms are efficient and consistent with the observed disk evolutionary timescales of...
Topics: NASA Technical Reports Server (NTRS), ACCRETION DISKS, ANGULAR MOMENTUM, MOLECULAR CLOUDS, MOMENTUM...
It is shown that the chemical composition of cosmic rays at their sources for the elements up to the atomic number as 80 is quite similar to that of the carbonaceous chondrites, which have been keeping the properties of the protosolar nebula. In particular, the similarity between these two compositions is significant to the elements classified as refractory and siderphile, in addition to the elements, Ca and Al. These results as cited above suggest that cosmic rays, being currently observed...
Topics: NASA Technical Reports Server (NTRS), CHEMICAL COMPOSITION, CHEMICAL ELEMENTS, CHONDRITES, COSMIC...
Primitive materials provide important clues on the processes that occurred during the formation and early evolution of the Solar System. Space-based and ground-based observations of cometary comae show that comets appear to contain a mixture of the products of both interstellar and nebular chemistries. Significant 15-nitrogen enrichments have been measured in CN and HCN towards a number of comets and may suggest an origin of interstellar chemical fractionation. Additionally, large N-15...
Topics: NASA Technical Reports Server (NTRS), CHEMICAL FRACTIONATION, COMETS, INTERSTELLAR CHEMISTRY,...
This final report contains a list of publications supported in whole or part by NAG9-108 in the time period 1 May 1985 to 30 April 1994. Also contained is a list of invited papers with abstracts supported in whole or part by this grant in the same time period. A copy of the 1993 paper by Ronald G. Prinn, 'Protostars and Planets III', is attached since it had not previously been sent to NASA.
Topics: NASA Technical Reports Server (NTRS), PLANETARY EVOLUTION, SOLAR SYSTEM, SOLAR SYSTEM EVOLUTION,...
No abstract available
Topics: NASA Technical Reports Server (NTRS), BROWN DWARF STARS, VARIABILITY, STELLAR COMPOSITION, STELLAR...
We perform numerical simulations of the growth of a Population III stellar system under photodissociating feedback. We start from cosmological initial conditions at z = 100, self-consistently following the formation of a minihalo at z = 15 and the subsequent collapse of its central gas to high densities. The simulations resolve scales as small as approx. 1 AU, corresponding to gas densities of 10(exp 16)/cu cm. Using sink particles to represent the growing protostars, we evolve the stellar...
Topics: NASA Technical Reports Server (NTRS), STELLAR MASS, POPULATION III STARS, MAIN SEQUENCE STARS,...
We present ground-based observations of the 2041/cm (4.9 micrometer) absorption feature toward the deeply embedded protostar W33A. We attribute this interstellar feature to solid carbonyl sulphide (OCS) embedded in icy grain mantles along the line of sight. We have made an extensive laboratory study of the infrared characteristics of OCS in various ice mixtures. Studies of the 2041/cm band of solid OCS and solid mixtures containing OCS show that its shape and peak position are sensitive to the...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION SPECTRA, CARBONYL COMPOUNDS, METHYL ALCOHOL,...
The Taurus molecular cloud supposedly has no star clusters but only isolated star formation. However, the Infrared Astronomical Satellite (IRAS) shows us that a small star cluster is currently forming in Taurus. Most of the sources are deeply embedded and are probably low-mass protostars. We use High Resolution (HiRes) images of the IRAS data from the Infrared Processing and Analysis Center (IPAC) to look for additional infrared members of the cluster. We also investigate the question of...
Topics: NASA Technical Reports Server (NTRS), EMBEDDING, INFRARED ASTRONOMY SATELLITE, MASS, MOLECULAR...
Using the IRTF cooled-grating spectrometer moderate resolution 2.4 to 3.8 micron spectra of a selection of IR protostars and one object located behind the Taurus dark cloud were obtained. Two examples of the spectra are presented. It is clear that the absorption near 3.07 micron is dominated by H2O ice and a comparison between the spectra and a simple H2O ice model allows a temperature estimate for the hottest ice-coated grains in these sources. Higher resolution observations showed no...
Topics: NASA Technical Reports Server (NTRS), ABSORPTION SPECTRA, INFRARED SPECTRA, INFRARED SPECTROSCOPY,...
Numerical two dimensional calculations of the formation of the solar nebula are presented. The following subject areas are covered: (1) observational constraints of the properties of the initial solar nebula; (2) the physical problem; (3) review if two dimensional calculations of the formation phase; (4) recent models with hydrodynamics and radiative transport; and (5) further evolution of the system.
Topics: NASA Technical Reports Server (NTRS), HYDRODYNAMICS, PLANETARY NEBULAE, PROTOSTARS, STELLAR...
This LTSA award funded my research on the origin of stellar X-ray emission and the validity of the solar-stellar analogy. This research broadly addresses the relevance of our current understanding of solar X-ray physics to the interpretation of X-ray emission from stars in general. During the past five years the emphasis has been on space-based X-ray observations of very young stars in star-forming regions (T Tauri stars and protostars), cool solar-like G stars, and evolved high-mass Wolf-Rayet...
Topics: NASA Technical Reports Server (NTRS), X RAY ASTRONOMY, X RAY STARS, ANALOGIES, SOLAR X-RAYS, T...
The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes, and is currently the largest scientific project under construction in the United States. It will be a large (6.6m) cold (50K) telescope launched in about 5 years into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. Science with the James Webb Space Telescope falls into four themes. The End of the Dark Ages: First...
Topics: NASA Technical Reports Server (NTRS), JAMES WEBB SPACE TELESCOPE, BLACK HOLES (ASTRONOMY),...
Anomalously fractionated isotopic material is found in many primitive Solar System objects, such as meteorites and comets. It has been suggested that these extreme isotope ratios, are tracers of interstellar chemistry. We will present observations of the nitrogen and carbon fractionation chemistry in dense molecular clouds, particularly in cores where sUbstantial freeze-out of molecules, namely CO, onto dust has occurred. Recent models have suggested that non-depleted species, carbon and...
Topics: NASA Technical Reports Server (NTRS), FRACTIONATION, INTERSTELLAR MATTER, CORES, MOLECULAR CLOUDS,...
The scientific capabilities of the James Webb Space Telescope (JWST) fall into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and active nuclei within them evolved from the epoch of reionization to the present. The Birth of Stars...
Topics: NASA Technical Reports Server (NTRS), JAMES WEBB SPACE TELESCOPE, CHEMICAL PROPERTIES, MORPHOLOGY,...
The progress is reported toward the goal of a complete theory of solar nebula formation, with an emphasis on three spatial dimension models of solar nebular formation and evolution. The following subject areas are covered: (1) initial conditions for protostellar collapse; (2) single versus binary star formation; (3) angular momentum transport mechanisms; (4) three dimensional solar nebula models; and (5) implications for planetary formation.
Topics: NASA Technical Reports Server (NTRS), BINARY STARS, COLLAPSE, PLANETARY NEBULAE, PROTOSTARS, STAR...
The Space Infrared Interferometric Telescope (SPIRIT) was designed to accomplish three scientific objectives: (1) learn how planetary systems form from protostellar disks and how they acquire their inhomogeneous chemical composition; (2) characterize the family of extrasolar planetary systems by imaging the structure in debris disks to understand how and where planets of different types form; and (3) learn how high-redshift galaxies formed and merged to form the present-day population of...
Topics: NASA Technical Reports Server (NTRS), SPACEBORNE TELESCOPES, SYSTEMS ENGINEERING, PLANETARY...
The dark cloud L1551 contains the best known examples of bipolar molecular outflow. Such outflows are assumed to be driven by winds from young stars embedded in a cloud but the mechanism for collimation of the outflows is still in doubt, though it has been much debated. Among the possibilities put forth to date are intrinsically anisotropic stellar winds, isotropic stellar winds collimated by interstellar toroidal shaped clouds on the order of 10(17) cm in size, or circumstellar disks of order...
Topics: NASA Technical Reports Server (NTRS), INTERSTELLAR MATTER, MOLECULAR CLOUDS, PROTOSTARS, STAR...
Observational results are reported from our surveys in the Northern Hemisphere (using the Onsala 20 m telescope) and the Southern Hemisphere (using the Mopra 22 m telescope) to search for 3 mm emission lines from carbon-chain-bearing species and other complex molecules in the envelopes of low-mass protostars. Based on a sample of approximately 60 sources, we find that carbon-chain-bearing species including HC3N (and C4H) are highly abundant in the vicinity of more than half of the observed...
Topics: NASA Technical Reports Server (NTRS), PROTOSTARS, CARBON, EMISSION SPECTRA, SOUTHERN HEMISPHERE,...
The 3 micron absorption spectra of sources seen in or behind molecular clouds generally show a variety of absorption features. Three separate absorptions are used to explain these features. The cooled-grating array spectrometer (CGAS) at the NASA Infrared Telescope Facility was used to obtain spectra of the late-type mass-loss star OH 0739-12 and the protostars MonR2 IRS-2 and IRS-3 (solid circles). The differences between the spectra are discussed.
Topics: NASA Technical Reports Server (NTRS), ABSORPTIVITY, LATE STARS, MOLECULAR CLOUDS, PROTOSTARS,...
In protostellar cores where the dust temperature has been raised above 100K and subsequently allowed to fall below the condensation temperature of methanol, recondensation on to cooling grains removes methanol molecules from the gas at rates.faster (about 1000 times) than those of chemical reactions. Molecular recondensation can have a profound effect on the chemical composition of hot cores. The methanol chemistry of hot cores is solved analytically and the trend in molecule binding energies...
Topics: NASA Technical Reports Server (NTRS), INTERSTELLAR MATTER, STAR FORMATION, EARLY STARS, PROTOSTARS,...
H(2-2), N2 and CO are the most abundant molecular constituents in astrophysical environments, including protostellar nebulae. Although some organic molecules may be produced on very long timescales by the irradiation of ices formed on the cold surfaces of interstellar grains and these molecules may be an important source of raw materials leading to the origin of life on Earth, pre-solar organics could be swamped by the efficient conversion of nebular H2, N2 and CO to simple organic materials.
Topics: NASA Technical Reports Server (NTRS), PROTOSTARS, BIOLOGICAL EVOLUTION, HYDROGEN, ICE, INTERSTELLAR...
The infrared emission bands (also known as the UIR bands.) have recently been observed in absorption at 3.25 micrometers in the ices surrounding a few proto-stellar objects at 11.2 micrometers in MonR2, and at 6.2 micrometers towards two sources near the galactic center. The UIR bands have been observed in emission for many years, but identifying these bands has proven to be both difficult and contentious as no one has yet found a single material that provides a good match to the features....
Topics: NASA Technical Reports Server (NTRS), POLYCYCLIC AROMATIC HYDROCARBONS, VAPOR PHASES, PROTOSTARS,...
Isotopic anomalies in presolar grains and other meteoritical components require nucleosynthesis in stellar interiors, condensation into dust grains in stellar envelopes, transport of the grains through the interstellar medium by stellar outflows, and finally injection of the grains into the presolar nebula. The proximity of the presolar cloud to these energetic stellar events suggests that a shock wave from a stellar outflow might have initiated the collapse of an otherwise stable presolar...
Topics: NASA Technical Reports Server (NTRS), HYDRODYNAMICS, MOLECULAR CLOUDS, NEBULAE, PROTOSTARS, SHOCK...
Aromatic hydrocarbons are an important class of molecules for both astrochemistry and astrobiology (Fig. 1). Within this class of molecules, polycyclic aromatic hydrocarbons (PAHs) are known to be ubiquitous in many astrophysical environments, and are likely present in interstellar clouds and protostellar disks. In dense clouds, PAHs are expected to condense onto grains as part of mixed molecular ice mantles dominated by small molecules like H2O,CH3OH, NH3, CO, and CO2. These ices are exposed...
Topics: NASA Technical Reports Server (NTRS), BENZENE, NAPHTHALENE, IONIZING RADIATION, POLYCYCLIC AROMATIC...
The FRESIP mission is optimized to detect the inner planets of a planetary system. According to the current paradigm of planet formation, these planets will probably be small Earth-sized objects. Ground-based radial-velocity programs now have the sensitivity to detect Jovian-mass planets in orbit around bright solar-type stars. We expect the more massive planets to form in the outer regions of a proto-stellar nebula. These two types of measurements will very nicely complement each other, as...
Topics: NASA Technical Reports Server (NTRS), DETECTION, G STARS, MAIN SEQUENCE STARS, NEBULAE, PHOTOMETRY,...
What is the environment for planet formation around extremely low mass stars? Is the environment around brown dwarfs and extremely low mass stars conducive and sufficiently massive for planet production? The determining conditions may be set very early in the process of the host object's formation. IRAS 16253-2429, the source of the Wasp-Waist Nebula seen in Spitzer IRAC images, is an isolated, very low luminosity ("VeLLO") Class 0 protostar in the nearby rho Ophiuchi cloud. We...
Topics: NASA Technical Reports Server (NTRS), BROWN DWARF STARS, INFRARED ASTRONOMY SATELLITE, PLANETARY...
We report new spectra of molecule-rich sources in the southern hemisphere obtained using the 22-meter Mopra telescope. Spectra and maps are presented of organic molecules detected between 30 and 50 GHz in the young Class 0 protostar Chamaeleon MMS-1. The large abundances of polyynes, cyanopolyynes and methanol may be indicative of a warm carbon chemistry in the dense gas surrounding this protostar. Spectra are also presented from a 78-96 GHz scan of the carbon-rich AGB star IRAS 15194-5115,...
Topics: NASA Technical Reports Server (NTRS), MICROWAVE SPECTRA, ORGANIC CHEMISTRY, PROTOSTARS, STELLAR...
