Related papers: Solar System Abundances of the Elements
Solar analogs, broadly defined as stars similar to the Sun in mass or spectral type, provide a useful laboratory for exploring the range of Sun-like behaviors and exploring the physical mechanisms underlying some of the Sun's most elusive…
We examine recent astronomical data to assess whether the sun and Solar System possess anomalous properties compared to other stars and exoplanetary systems, providing context for astrobiology research. Utilising data primarily from large…
Computed color indices and spectral shapes for individual stars are routinely compared with observations for essentially all spectral types, but absolute fluxes are rarely tested. We can confront observed irradiances with the predictions…
Helioseismology has allowed us to study the structure of the Sun in unprecedented detail. One of the triumphs of the theory of stellar evolution was that helioseismic studies had shown that the structure of solar models is very similar to…
We have conducted a differential elemental abundance analysis of unprecedented accuracy (0.01 dex) of the Sun relative to 11 solar twins from the Hipparcos catalogue and 10 solar analogs from planet searches. We find that the Sun shows a…
This topical collection summarizes recent advances in observing and modeling irradiance variations of the Sun and Sun-like stars, emphasizing the links between surface magnetic fields and the resulting solar and stellar variability. In…
The past few years have seen a steady progress in the determination of element abundances at high redshifts, with new and more accurate measures of metallicities in star-forming galaxies, in QSO absorbers, and in the intergalactic medium.…
Recent data lead us to a simple and intriguing form of the neutrino mass matrix. In particular, we find solar neutrino oscillations to be nearly maximal (and rule out the small-angle MSW explanation of solar neutrino observations) if relic…
Current problems encountered in the spectroscopic determination of photospheric abundances are outlined and exemplified in a reevaluation of C, N, O, Ne, Mg, Si, and Fe, taking effects of NLTE and granulation into account. Updated…
Understanding the origin of comets requires knowledge of how the Solar System formed from a cloud of dust and gas 4.567 Gyr ago. Here, a review is presented of how the remnants of this formation process, meteorites and to a lesser extent…
Stellar model atmospheres form the basis for any element abundance determination and hence are crucial ingredients for studies of stellar, galactic and cosmic evolution. With recent observational progress with the advent of 8m-class…
Recent analyses of solar photospheric abundances suggest that the oxygen abundance in the solar atmosphere needs to be revised downwards. In this study we investigate the consequence of this revision on helioseismic analyses of the depth of…
High resolution images at different wavelengths, spectrograms and magnetograms, representing different levels of the solar atmosphere obtained with Hinode have been combined to study the 3-dimensional structure of the small magnetic…
The conditions of thermodynamic equilibrium, local thermodynamic equilibrium, and statistical equilibrium are discussed in detail. The equations of statistical equilibrium and the supplementary equations are shown together with the…
This encyclopedia article addresses questions like the following. How does the Sun shine? Does the neutrino have a mass? Are there weak interactions beyond those described by the standard model of particle physics?
We describe the current status of solar modelling and focus on the problems originated with the introduction of solar abundance determinations with low CNO abundance values. We use models computed with solar abundance compilations obtained…
Several investigations of FGK stars in the solar neighborhood have suggested that thin-disk stars with an iron abundance similar to the Sun appear to show higher abundances of other elements, such as silicon, titanium, or nickel. Offsets…
Star-to-star variations in abundances of the light elements carbon, nitrogen, oxygen, and sodium have been observed in stars of all evolutionary phases in all Galactic globular clusters that have been thoroughly studied. The data available…
The solar abundances have undergone a major downward revision in the last decade, reputedly as a result of employing 3D hydrodynamical simulations to model the inhomogeneous structure of the solar photosphere. The very low oxygen abundance…
There have been recent downward revisions of the solar photospheric abundances of Oxygen and other heavy elements. These revised abundances along with OPAL opacities are not consistent with seismic constraints. In this work we show that the…