Giant Stars in the Universe
Topics: Giant Stars, Universe
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May 23, 2019
05/19
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ObsidianAnt
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Link to YouTube version: https://www.youtube.com/watch?v=C8ebABHEqR0 Video created by ObsidianAnt . R ights to the gameplay footage belongs to Frontier Developments . Ever in search of unique areas to explore, I head out to the nebulas around Jaques Station. Hades Edge Location: HD 49368 Music The Event Horizon 1 - Johannes Bornlöf Skyburst 4 - Rannar Sillard I Will Not Be Shaken 1 - Johannes Bornlöf Skyburst 3 - Rannar Sillard Buy Elite: Dangerous: http://click.linksynergy.com/fs-bin/c......
Topics: Elite Dangerous, Discovery, Giant Stars, Gaming, YouTube
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1.7K
Nov 25, 2008
11/08
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analogik.com
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http://www.giantstars.de shows you how little our planet is compared to some of the biggest stars in the known universe.
Topics: giant stars, star, planet, planets, 3d, animation, space, universe, solar system, sun
a) Symbiotic Binary System: White dwarf + red giant system. b) Nova: White dwarf builds up mass envelope to the point of thermonuclear fusion. c) Dramatic increase in visual magnitude. d) Recurrent Nova? e) Hints but no strong confirmation of previous nova f) Pre-nova activity: 1) White dwarf shows ongoing variability at level of several in magnitude. 2) V407 Cyg companion is a Mira star showing variability at level of several in magnitude. g) Origin of the gamma rays? 1) Strong shock...
Topics: NASA Technical Reports Server (NTRS), GAMMA RAYS, BINARY STARS, PARTICLE DECAY, RED GIANT STARS,...
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Jul 21, 2010
07/10
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Clayton, D. D
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Thermal condensation, cold sticking, and sputtering by interstellar shock are combined with a chemical memory of the condensation sequence to account for depletion of aluminum, calcium, and titanium in interstellar gas. The extra depletion of aluminum and calcium becomes an indicator of the structural history of the refractory parts of interstellar grains.
Topics: DUST, GIANT STARS, STELLAR ENVELOPES, SUPERGIANT STARS, GRAIN SIZE, MOLECULAR INTERACTIONS,...
Recently, we discovered with International Ultraviolet Explorer (IUE) an F0-F2 IV-V companion to the T(sub c)-deficient S star HD 191589. If the magnitude difference is (delta)V=3.7, as indicated by several arguments, and E(B-V) = 0.0, we obtain a value of M(sub v)= - 1.5 +/- 0.4 for the Peculiar Red Giant (PRG), too faint for it to be a thermally-pulsing asymptotic giant branch star. According to the binary mass-transfer hypothesis for T(sub c)-deficient PRG's, a white dwarf must be the source...
Topics: NASA Technical Reports Server (NTRS), S STARS, RED GIANT STARS, IUE, MASS TRANSFER, CONTAMINATION,...
IUE and H alpha observations continued on a two-year program to monitor the UV variability of three interacting peculiar red giant (PRG) binaries, HD 59643 (C6,s), HD 35155 (S3/2), and HR 1105 (S3.5/2.5). All of these systems were suspected to involve accretion of material from the PRG to a white-dwarf secondary, based mainly on previous IUE investigations. They were primary candidates from earlier surveys of PRG's to test the hypothesis that the Tc-poor PRG's are formed as a result of mass...
Topics: NASA Technical Reports Server (NTRS), IUE, RED GIANT STARS, HYPOTHESES, MASS TRANSFER, SURVEYS,...
Using HST/GHRS, HST/STIS and FUSE archival data for alpha Tau and the CHIANTI spectroscopic code, we have derived line shifts, volumetric emission measures, and plasma density estimates, and calculated filling factors for a number of UV lines forming between 10,000 K and 300,000 K in the outer atmosphere of this red giant star. The data suggest the presence of low-temperature extended regions and high-temperature compact regions, associated with magnetically open and closed structures in the...
Topics: NASA Technical Reports Server (NTRS), LATE STARS, RED GIANT STARS, GIANT STARS, ATMOSPHERIC...
Using HST/GHRS, HST/STIS and FUSE archival data for a Tau and the CHIANTI spectroscopic code, we have derived line shifts, volumetric emission measures, and plasma density estimates, and calculated filling factors for a number of UV lines forming between 10,000 K and 300,000 K in the outer atmosphere of this red giant star. The data suggest the presence of low-temperature extended regions and high-temperature compact regions, associated with magnetically open and closed structures in the...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, MAGNETOHYDRODYNAMIC WAVES, RED GIANT STARS,...
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Jul 21, 2010
07/10
by
Neal, V
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The purpose of the Solar Maximum Repair Mission is to restore the operational capacity of the satellite by replacing the attitude control system module and servicing two of the scientific instruments on board. The mission will demonstrate the satellite servicing capacity of the Space Shuttle for the first time.
Topics: CHROMOSPHERE, RADIATION PRESSURE, STELLAR MASS, INTERSTELLAR MATTER, RED GIANT STARS, STELLAR...
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Jul 21, 2010
07/10
by
Puetter, R.; Krinsky, I
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A number of issues involving grain charging in the interstellar medium were discussed. Such effects include: (1) stark broadening of molecular spectral features, (2) electrostatic grain rupturing, (3) enhancements in particle-grain collision cross sections, and (4) excitation of molecular rotations and/or vibrations.
Topics: GIANT STARS, INTERSTELLAR MATTER, STELLAR ENVELOPES, STELLAR MASS EJECTION, CHEMICAL COMPOSITION,...
An analytic expression for the integrated H alpha optical depth profile is derived for a one dimensional slab geometry model chromosphere, with electron temperature increasing as a power law with height. The formula predicts H alpha opacity and profile width to be sensitive functions of the thermal gradient. Application of the model to observation reveals that broad H alpha absorption widths in G and K giant stars are consistent with a mean H alpha chromospheric optical depth of 50, while...
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, OPTICAL PROPERTIES, TEMPERATURE GRADIENTS,...
Brief factual reviews are provided for supernovae, pulsars and neutron stars, and black holes. Also discussed in general terms are red giants, white dwarfs, quasars and radio galaxies.
Topics: NASA Technical Reports Server (NTRS), BLACK HOLES (ASTRONOMY), PULSARS, SUPERNOVAE, QUASARS, RADIO...
The research programs are highlighted in the following areas: major planets; planetary satellites and rings; asteroids; comets; dark organic matter; theoretical and analytical structures; extrasolar planetary; and telescopes.
Topics: NASA Technical Reports Server (NTRS), ASTEROIDS, COMETS, GIANT STARS, PLANETOLOGY, RESEARCH AND...
Dust formation around cool giant and supergiant stars is examined in terms of grain formulation. Optical properties of small clusters, molecular physics of cluster nucleation and growth, circumstellar mass flows, and their application to alpha Ori are discussed.
Topics: NASA Technical Reports Server (NTRS), DUST, GIANT STARS, STELLAR ENVELOPES, SUPERGIANT STARS, GRAIN...
The purpose was to study various aspects of mass loss in stars of different types. The observational part of the research was directed at three Cepheid variables; the archival part of the research was directed at hot stars (for information on corotating interaction regions) and at cool giants (for study of variability in the mass losing part of the atmosphere).
Topics: NASA Technical Reports Server (NTRS), CEPHEID VARIABLES, COOL STARS, GIANT STARS, HOT STARS,...
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165
Jul 21, 2010
07/10
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Buseck, P. R
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Possible compounds for the 9.7 micron spectral feature and the 2175A spectral bump are examined. Results from electron microscopy and high resolution transmission electron microscopy are discussed.
Topics: COSMIC DUST, INFRARED SPECTRA, RADIO SPECTRA, RADIATION PRESSURE, RED GIANT STARS, STELLAR...
The dynamic behavior of the H-rich envelope (0.101 solar mass) of an evolved star (1.1 solar mass) as the luminosity rises to 19000 solar luminosity during the second ascent of the red giant branch. For luminosities in the range 3100 L 19000 solar luminosity the H-rich envelope pulsates like a long-period variable (LPV) with periods of the order of a year. As L reaches 19000 solar luminosity, the entire H-rich envelope is ejected as a shell with speeds of a few 10 km/s. The ejection occurs on a...
Topics: NASA Technical Reports Server (NTRS), STELLAR EVOLUTION, STELLAR MASS EJECTION, GIANT STARS,...
DK UMa (= 24 UMa = HD 82210) is a G4 IV-III star. According to its M(sub v) and B - V color, it is located at the base of the red giant branch, having recently exited from the Hertzsprung Gap. Now poised to start its first ascent along the giant branch, DK UMa is at a significant juncture in its post-main-sequence evolution, offering an important evolutionary comparison for magnetic activity with stars like 31 Comae, which is just entering the Hertzsprung Gap, and older stars like the Hyades...
Topics: NASA Technical Reports Server (NTRS), EMISSION SPECTRA, MAGNETIC VARIATIONS, GIANT STARS,...
Among warm giant stars, rapid mass loss sets in along a well defined velocity dividing line (VDL). Hot corona also disappear close to the VDL and thermal pressure cannot drive the observed rapid mass loss in these stars. The VDL may be associated with magnetic fields changing from closed to open. Such a change is consistent with the lack of X-rays from late-type giants. A magnetic transition locus based on Pneuman's work on helmet streamer stability agrees well with the empirical VDL. The...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, MAGNETIC FIELDS, STELLAR MASS EJECTION, STELLAR...
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273
May 26, 2011
05/11
by
Lollar, Louis F.; Maus, Louis C
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Marshall Space Flight Center (MSFC) is the National Aeronautics and Space Administration's (NASA) lead center for space transportation systems development. These systems include earth to orbit launch vehicles, as well as vehicles for orbital transfer and deep space missions. The tasks for these systems include research, technology maturation, design, development, and integration of space transportation and propulsion systems. One of the key elements in any transportation system is the...
Topics: BINARY STARS, TRAJECTORIES, STELLAR WINDS, MASS TRANSFER, ASYMPTOTIC GIANT BRANCH STARS, STELLAR...
The filter photometers in the Wisconsin Experiment Package on OAO-2 were used to obtain data for a carefully selected set of 24 blue Ap stars and 31 comparison standard B and A dwarfs and giants for a program of relative photometry. Observations were made in seven bandpasses over the effective wavelength range 1430A-4250A. The Ap stars observed include members of the Si, Hg-Mn and Sr-Cr-Eu peculiarity classes. Most of them are too blue in B-V for their published MK spectral classes. The blue Ap...
Topics: NASA Technical Reports Server (NTRS), OAO 2, OPTICAL FILTERS, PHOTOMETRY, STARS, A STARS, B STARS,...
The chemical composition of the Crab Nebula is compared with several presupernova models. The small carbon and oxygen abundances in the helium-rich nebula are consistent with only the presupernova model of the star whose main sequence mass was MMS approximately 8-9.5 M. More massive stars contain too much carbon in the helium layer and smaller mass stars do not leave neutron stars. The progenitor star of the Crab Nebula lost appreciable part of the hydrogen-rich envelope before the...
Topics: NASA Technical Reports Server (NTRS), CHEMICAL COMPOSITION, CRAB NEBULA, NEUTRON STARS, SUPERNOVA...
For red giants a smooth increase in the nitrogen to carbon abundance ratio for increasing B-V as is expected for the first dredge up phase when the outer convection zone deepens is found. An average increase in the nitrogen to silicon ratio for B-V = 0.6 which goes back to almost solar values for cool giants with B - V approximately 1.0 is reported. It looks as if Si would be enriched for deeper mixing contrary to expectations from standard evolution theory.
Topics: NASA Technical Reports Server (NTRS), ABUNDANCE, GIANT STARS, IUE, SPACEBORNE ASTRONOMY,...
Model atmosphere calculations are used to assess whether an empirically derived relation between V-R and surface brightness is independent of a variety of stellar paramters, including surface gravity. This relationship is used in a variety of applications, including the determination of the distances of Cepheid variables using a method based on the Beade-Wesselink method. It is concluded that the use of a main sequence relation between V-R color and surface brightness in determining radii of...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, BRIGHTNESS TEMPERATURE, STELLAR...
The circumstellar envelopes surrounding late-type giants and supergiants were studied using high resolution, photoelectric scans of strong optical resonance lines. A method for extracting the circumstellar from the stellar components of the lines allowed a quantitative determination of the physical conditions in the envelopes and the rates of mass loss at various positions in the red giant region of the HR diagram. The observed strengthening of the circumstellar spectrum with increasing...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, STELLAR MASS, SUPERGIANT STARS,...
High-resolution IUE spectra of the Mg II k line of HD 199178 were analyzed, applying spectral imaging techniques to derive an image of the chromospheric structure and to study the transient behavior of the chromosphere. All spectra in the IUE archives were uniformly reduced and analyzed. Results are compared with ground-based observations of the photosphere. Four ultraviolet flares on HD 199178 are observed; 3 of these occurred at roughly the same rotational phase. There is no clear...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, IUE, SPACEBORNE ASTRONOMY, STELLAR FLARES,...
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306
May 23, 2011
05/11
by
Ortega, James M
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The research of this project concerned the investigation of the suitability of the SOR iteration as a preconditioner for the GMRES method for solving large sparse nonsymmetric systems of linear equations. Preliminary results on a serial computer (RS 6000) showed that SOR was indeed a good preconditioner, at least for the convection-diffusion equations used in this study. This was in contradiction to various statements that had appeared in the literature, questioning the suitability of SOR as a...
Topics: GIANT STARS, CORONAS, HYDROGEN, STELLAR LUMINOSITY, PHOTOSPHERE, OPEN CLUSTERS, STELLAR ACTIVITY,...
A multistep scenario which describes a plausible mass loss mechanism associated with red giant and related stars is outlined. The process involves triggering a condensation instability in an extended chromosphere, leading to the formation of cool, dense clouds which are conducive to the formation of molecules and dust grains. Once formed, the dust can be driven away from the star by radiation pressure. Consistency with various observed phenomena is discussed.
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, INTERSTELLAR MATTER, RED GIANT STARS, STELLAR...
Coronal heating by resonant absorption of Alfvenic surface waves (quiescent), and magnetic tearing instabilities (impulsive), is discussed with emphasis on three principles which may have application to late-type evolved stars. (1) If sq B/8 pi greater than sq. rho V is observed 2 in a stellar atmosphere, then the observed magnetic field must originate in an interior dynamo. (2) Low mass loss rates could imply the presence of closed magnetic flux loops within the outer atmosphere which...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, M STARS, MAGNETIC FLUX, STELLAR MAGNETIC FIELDS,...
We present the numerical simulations of winds from evolved giant stars using a fully non-linear, time dependent 2.5-dimensional magnetohydrodynamic (MHD) code. This study extends our previous fully non-linear MHD wind simulations to include a broadband frequency spectrum of Alfven waves that drive winds from red giant stars. We calculated four Alfven wind models that cover the whole range of Alfven wave frequency spectrum to characterize the role of freely propagated and reflected Alfven waves...
Topics: NASA Technical Reports Server (NTRS), STELLAR WINDS, BROADBAND, MAGNETOHYDRODYNAMIC WAVES, RED...
Stars of various types are believed to be the main source of interstellar (IS) dust grans. The most important confirmed source is evolved giant and supergiant stars. Supernovae also contribute to the mass loss. The differences between circumstellar (CS) and IS dust were reviewed using the following topics: alteration of CS dust grains, size distribution, space observation of CS and IS dust, comparison of infrared spectra, isotopic signatures, Magellanic clouds and nearby galaxies, life cycles...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, INTERSTELLAR MATTER, STELLAR ENVELOPES, STELLAR...
No abstract available
Topics: NASA Technical Reports Server (NTRS), KEPLER MISSION, STELLAR ATMOSPHERES, GIANT STARS, DWARF...
The final report on 'Ultraviolet Observations of Astronomical Sources,' which ran for a total of three years, roughly between 1 July 1988 and 14 Feb. 1993 is presented. During the first year, I worked at Indiana University; since October, 1989, I have been at Tennessee State University. This grant has supported my studies of archival International Ultraviolet Explorer (IUE) observations of zeta Aur binaries, cool stars that are paired with hot stars in binary systems. Such systems are important...
Topics: NASA Technical Reports Server (NTRS), BINARY STARS, CHROMOSPHERE, IUE, ULTRAVIOLET ASTRONOMY, COOL...
Detached close binary systems define the main sequence band satisfactorily, but very little is known about the masses of giants and supergiants. High dispersion international ultraviolet explorer satellite observations promise an improvement, since blue companions are now frequently found to late type supergiants. Mu Sagittaril and in particular Xi Aurigae are discussed in more detail. The barium star abundance anomaly appears to be due to mass transfer in interacting systems. The symbiotic...
Topics: NASA Technical Reports Server (NTRS), BINARY STARS, GIANT STARS, IUE, STELLAR EVOLUTION, SUPERGIANT...
The structure of the Mira variables is discussed with particular emphasis on the extent of their observable atmospheres, the various methods for measuring the sizes of these atmospheres, and the manner in which the size changes through the cycle. The results obtained by direct, photometric and spectroscopic methods are compared, and the problems of interpretation are addressed. Also, a simple model for the atmospheric structure and motions of Miras based on recent observations of the doubling...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, MIRA VARIABLES, STELLAR ATMOSPHERES, STELLAR...
During the seventh year of IUE twenty-six spectra of seventeen cool giant stars ranging in spectral type from K3 thru M6 were obtained. Together with spectra of fifteen stars observed during the sixth year of IUE, these low-resolution spectra have been used to: (1) examine chromospheric activity in the program stars and late type giants in general, and (2) evaluate the extent to which nonradiative heating affects the upper levels of cool giant photospheres. The stars observed in this study all...
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, COOL STARS, EMISSION SPECTRA, GIANT STARS, IUE,...
In the outer envelopes of red giants, when the gas cools sufficiently, molecules and solids form. Thermodynamically, the most stable molecule is CO, and it is usually assumed that all the available carbon and oxygen are consumed in the formation of this molecule (Salpeter 1977). If the carbon abundance is greater than the oxygen abundance, then the carbon left over after the formation of CO is available for solid grains. Because carbon is by far the most abundant species available for making...
Topics: NASA Technical Reports Server (NTRS), ASTRONOMY, ASTROPHYSICS, CARBON, INTERPLANETARY DUST, RED...
Photoelectric spectral scans at 30-A resolution of 9 dwarfs, 10 giants and 6 supergiants with spectral types GO to M5 were presented. All stars were observed every 4 A from wavelength 3300 to wavelength 7000. Absorption features at this resolution coincide with: strong atomic lines of Fe 1,11, Ca 1,11, Mg 1, and Na 1; vibrational bands of the electronic transitions of TiO, MgH, CaH, SiH, AlH, Cn, Ch, C2, OH, and NH. The dependence of the wavelength 3740 Fe 1 blend and the wavelength 3440...
Topics: NASA Technical Reports Server (NTRS), COOL STARS, SCANNERS, SPECTROPHOTOMETRY, STARS, DWARF STARS,...
The largest body of data on ultraviolet spectra of late-type stars now available is the series of scans made with the long wavelength spectrometer onboard OAO-2. Some features of selected scans from this series and estimates of Mg II emission fluxes were reported earlier. Since that time, the effects of sky background, scattered light and variable instrumental sensitivity have become better understood. Additional stars are used to define more clearly the transition from Mg II 2800 A absorption...
Topics: NASA Technical Reports Server (NTRS), GIANT STARS, MAGNESIUM, OAO 2, SPECTRAL LINE WIDTH,...
The average spectral energy distribution for a sample of 3200 A. Spectral synthesis indicates that elliptical galaxies are most likely older than 9 Gyrs. The ultraviolet flux is consistent with a population of red horizontal branch stars, as those present in metal-rich globular clusters. Data for distant (Z approximately 1) first ranked cluster galaxies show indications of spectral evolution.
Topics: NASA Technical Reports Server (NTRS), ELLIPTICAL GALAXIES, GALACTIC EVOLUTION, IUE, SPECTRAL ENERGY...
An overview of the significance for physics of the closest visual supernova in almost 400 years is presented. The supernova occurred in the Large Magellanic Cloud (LMC), approx. 50 kpc away. The supernova star was a massive star of approx. 15 to 20 solar mass. Observations now show that it was once a red giant but lost its outer envelope. The lower than standard luminosity and higher observed velocities are a natural consequence of the pre-supernova star being a blue rather than a red...
Topics: NASA Technical Reports Server (NTRS), LIGHT CURVE, MAGELLANIC CLOUDS, NEUTRINOS, NUCLEAR FUSION,...
Interstellar dust grains are presumed in part to have their origins in the outer atmospheres of red giant and supergiant stars because, despite the efficiency of shock destruction of grains in the interstellar medium (ISM), meteoritic samples possess isotopic signatures that are consistent with nucleosynthetic origin in the interior of evolved stars. There is ample evidence to suggest that once dust grains form near red giants and supergiants, radiation pressure is sufficient to drive them to...
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, COSMIC DUST, INTERSTELLAR MATTER, RED GIANT...
An opacity sampling (OS) technique for treating the radiative opacity of large numbers of atomic and molecular lines in cool stellar atmospheres is presented. Tests were conducted and results show that the structure of atmospheric models is accurately fixed by the use of 1000 frequency points, and 500 frequency points is often adequate. The effects of atomic and molecular lines are separately studied. A test model computed by using the OS method agrees very well with a model having identical...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC OPTICS, ATOMIC SPECTRA, MOLECULAR SPECTRA,...
The activity in RS Canum Venaticorum (CVn) is investigated. Models for chromospheric structure are developed and the role of magnetic fields both in the photosphere as well as in the chromosphere and upper atmosphere are examined. T Tau stars are also studied from the same points of view. The properties of magnetic field loops are used to help understand the atmospheric structure in RS CVn stars. The concepts developed in the case of these stars appear to be applicable over a much broader...
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, GIANT STARS, PHOTOSPHERE, STELLAR MAGNETIC...
Radial velocity measurements are being made to search for planets orbiting stars other than the Sun. The reflex acceleration induced on stars by planets can be sensed by measuring the small, slow changes in the line-of-site velocities of stars. To detect these planetary perturbations, the data series must be made on a uniform instrumental scale for as long as it takes a planet to orbit its star. A spectrometer of extreme stability and unprecedented sensitivity to changes in stellar radial...
Topics: NASA Technical Reports Server (NTRS), ASTRONOMICAL SPECTROSCOPY, EXTRASOLAR PLANETS, PLANETARY...
Using HST/GHRS, HST/STIS and FUSE archival data for alpha Tau and the CHIANTI spectroscopic code, we have derived line shifts, volumetric emission measures, and plasma density estimates, and calculated filling factors for a number of UV lines forming between 10,000 K and 300,000 K in the outer atmosphere of this red giant star. The data suggest the presence of low-temperature extended regions and high-temperature compact regions, associated with magnetically open and closed structures in the...
Topics: NASA Technical Reports Server (NTRS), MAGNETOHYDRODYNAMIC WAVES, GIANT STARS, ATMOSPHERIC PHYSICS,...
A very strong Brackett-gamma hydrogen emission line, and the 2.3 micron CO stellar absorption feature were measured in NGC 253. The presence and strength of the CO feature indicates that late type giant stars produce most of the 2.2 micron continuum emission, while the rate of ionization implied by strength of the Brackett-gamma line indicates that much, perhaps all, of the luminosity detected at far infrared wavelengths originates from a large number of OB stars. As compared to the...
Topics: NASA Technical Reports Server (NTRS), EMISSION SPECTRA, GALAXIES, H GAMMA LINE, CARBON MONOXIDE,...
The dependence of the red edge location on the two fundamental free parameters in the eddy viscosity treatment was extensively studied. It is found that the convective flux is rather insensitive to any reasonable or allowed value of the two free parameters of the treatment. This must be due in part to the fact that the convective flux is determined more by the properties of the hydrogen ionization region than by differences in convective structure. The changes in the effective temperature of...
Topics: NASA Technical Reports Server (NTRS), CONVECTIVE FLOW, EDDY VISCOSITY, GIANT STARS, RED SHIFT,...
Astration of heavy elements by the stars of the Milky Way forms a fossil record which may preserve spacial distribution of the mass function for the stars in the galaxy. Sulfur is among the last common element for which the relative abundance of its various isotopes have yet to be completely measured within our galaxy. Explosive oxygen burning in massive stars is thought to be the process which dominates sulfur production within stars. There models predict that the various isotopes (S-32, S-33,...
Topics: NASA Technical Reports Server (NTRS), ABUNDANCE, GALACTIC STRUCTURE, MILKY WAY GALAXY, STELLAR...
