Silicon isotopic abundance toward evolved stars and its application
... Results. The 29 Si/30 Si ratios inferred from the thermal SiO emission tend to be lower toward low-mass oxygen-rich stars (e.g., down to about unity for W Hya), and close to an interstellar or solar value of 1.5 for the higher-mass carbon star IRC+10216 and two red supergiants. There is a tentative ...
... Results. The 29 Si/30 Si ratios inferred from the thermal SiO emission tend to be lower toward low-mass oxygen-rich stars (e.g., down to about unity for W Hya), and close to an interstellar or solar value of 1.5 for the higher-mass carbon star IRC+10216 and two red supergiants. There is a tentative ...
The Circumstellar Environments of Young Stars at AU Scales
... We review recent advances in our understanding of the innermost regions of the circumstellar environment around young stars, made possible by the technique of long-baseline interferometry at infrared wavelengths. Near-infrared observations directly probe the location of the hottest dust. The charact ...
... We review recent advances in our understanding of the innermost regions of the circumstellar environment around young stars, made possible by the technique of long-baseline interferometry at infrared wavelengths. Near-infrared observations directly probe the location of the hottest dust. The charact ...
The Cosmos in Your Pocket: How Cosmological
... converted to precise angular positions against the Sun from which a parallax angle could be derived. It was expected that Venus, passing closer to the Earth than Mars or Mercury, would yield a larger angle, and would therefore be easier to measure. Halley also did not live to see this prediction ful ...
... converted to precise angular positions against the Sun from which a parallax angle could be derived. It was expected that Venus, passing closer to the Earth than Mars or Mercury, would yield a larger angle, and would therefore be easier to measure. Halley also did not live to see this prediction ful ...
GammaRay Bursts, the Strongest Explosions in the Universe.
... The extra‐galactic origin was not easily accepted. It required the release of a huge amount of energy in a short time. An extra‐galactic GRB releases in a few seconds the energy released by a star like our Sun during its whole lifetime, several billion years. It was hard ...
... The extra‐galactic origin was not easily accepted. It required the release of a huge amount of energy in a short time. An extra‐galactic GRB releases in a few seconds the energy released by a star like our Sun during its whole lifetime, several billion years. It was hard ...
SPIRou Science Case
... atmospheric transit as possible on the one hand, and as bright a star as possible on the other hand (in the nIR, where absorption from atmospheric molecules mostly concentrates), M dwarfs are optimal targets for this quest (Rauer et al 2011, A&A 529, 8). Today, only a handful of very-bright transiti ...
... atmospheric transit as possible on the one hand, and as bright a star as possible on the other hand (in the nIR, where absorption from atmospheric molecules mostly concentrates), M dwarfs are optimal targets for this quest (Rauer et al 2011, A&A 529, 8). Today, only a handful of very-bright transiti ...
THE VELOCITY DISTRIBUTION OF THE NEAREST
... pickup ions inside the solar system (formed by interactions of interstellar neutrals with the solar wind) and interstellar absorption lines toward nearby stars have been used to constrain the first full radiative transfer model of nearby ISM (SF02). These results indicate that the interstellar proper ...
... pickup ions inside the solar system (formed by interactions of interstellar neutrals with the solar wind) and interstellar absorption lines toward nearby stars have been used to constrain the first full radiative transfer model of nearby ISM (SF02). These results indicate that the interstellar proper ...
PDF only - at www.arxiv.org.
... advantage of the recent progress in Hot Electron Bolometer (HEB) technology, providing higher sensitivity. Together with a larger collecting area compared to Herschel observations of dedicated solar longitudes over a full martian year would provide for the first time vert ...
... advantage of the recent progress in Hot Electron Bolometer (HEB) technology, providing higher sensitivity. Together with a larger collecting area compared to Herschel observations of dedicated solar longitudes over a full martian year would provide for the first time vert ...
Introduction
... a dataset of multiwavelength observations for a new sample of galaxies. The sample is volume and mass limited, and includes galaxies of all morphological types inhabiting a range of different environments, from galaxies in the dense core of the Virgo cluster to relatively isolated systems. As such, ...
... a dataset of multiwavelength observations for a new sample of galaxies. The sample is volume and mass limited, and includes galaxies of all morphological types inhabiting a range of different environments, from galaxies in the dense core of the Virgo cluster to relatively isolated systems. As such, ...
The Oort cloud as a remnant of the protosolar nebula
... to Whitworth & Summers, an infinite number of types of density behaviour outside the shock front can occur for one given type of behaviour inside the front. We empirically find and utilize the fact that the appropriate numerical integration always results in the same behaviour outside the shock fron ...
... to Whitworth & Summers, an infinite number of types of density behaviour outside the shock front can occur for one given type of behaviour inside the front. We empirically find and utilize the fact that the appropriate numerical integration always results in the same behaviour outside the shock fron ...
Spot sizes on Sun-like stars
... 6 in Table 2) are taken from Henry et al. (1995), Rodonò et al. (2000) and Padmakar & Pandey (1999) and are labelled H+, R+ and PP, respectively, in column 7. The covering fractions derived from photometry by Henry et al. (1995) are lower limits as they have used the maximum light level during each ...
... 6 in Table 2) are taken from Henry et al. (1995), Rodonò et al. (2000) and Padmakar & Pandey (1999) and are labelled H+, R+ and PP, respectively, in column 7. The covering fractions derived from photometry by Henry et al. (1995) are lower limits as they have used the maximum light level during each ...
Search for an exosphere around 51 Pegasi B with ISO
... line width and compare to the noise level (quantitative check for criterion 2). Table 2 provides the signal/noise ratio (S/N) for all bands in a wavelength range near the band center and free of strong stellar absorptions. To determine the noise, the decreasing flux level of the star with wavelength ...
... line width and compare to the noise level (quantitative check for criterion 2). Table 2 provides the signal/noise ratio (S/N) for all bands in a wavelength range near the band center and free of strong stellar absorptions. To determine the noise, the decreasing flux level of the star with wavelength ...
observations of white dwarfs in the solar neighborhood
... Harris et al. 2003), and the discovery of another object with similar characteristics has implications for the two-phase accretion model of Dupuis, Fontaine, & Wesemael (1993): a similar abundance pattern would imply similar accretion rates. To determine the heavy-element abundance in NLTT 40607, we ...
... Harris et al. 2003), and the discovery of another object with similar characteristics has implications for the two-phase accretion model of Dupuis, Fontaine, & Wesemael (1993): a similar abundance pattern would imply similar accretion rates. To determine the heavy-element abundance in NLTT 40607, we ...
Analysis of Angular Momentum in Planetary Systems and Host Stars
... spin down of low-mass stars2 especially appears to be tied to active surface convective zones (Schatzman, 1962) and stellar winds produced by chromospherically active surfaces (Mestel, 1968). Most rotational slow-down for all stars appears to occur during Pre-Main Sequence (PMS) contraction, but add ...
... spin down of low-mass stars2 especially appears to be tied to active surface convective zones (Schatzman, 1962) and stellar winds produced by chromospherically active surfaces (Mestel, 1968). Most rotational slow-down for all stars appears to occur during Pre-Main Sequence (PMS) contraction, but add ...
The Witness of the Stars
... Beigh, the Tartar prince and astronomer, about AD 1450, who gives the Arabian astronomy as it had come down from the earliest times. Modern astronomers have preserved, and still have in common use, the ancient names of over a hundred of the principal stars which have been handed down; but now these ...
... Beigh, the Tartar prince and astronomer, about AD 1450, who gives the Arabian astronomy as it had come down from the earliest times. Modern astronomers have preserved, and still have in common use, the ancient names of over a hundred of the principal stars which have been handed down; but now these ...
Sample syllabus 2 - Johns Hopkins Center for Talented Youth
... Course Description: When the sun runs out of fuel, will it explode in a giant supernova or fade out into a white dwarf? Does every galaxy revolve around a super-massive black hole? Will the universe continue to expand, or will it eventually collapse back upon itself in a reversal of the Big Bang? As ...
... Course Description: When the sun runs out of fuel, will it explode in a giant supernova or fade out into a white dwarf? Does every galaxy revolve around a super-massive black hole? Will the universe continue to expand, or will it eventually collapse back upon itself in a reversal of the Big Bang? As ...
Spectropolarimetry of the massive post
... structure, along the short axis of the extended reflection nebulosity. Long term pho tometry reveals that the star increased in temperature until the mid -nineties, after which the photospheric flux in the optical levelled off. As the photometric changes are mostly probed in the red, they do not tra ...
... structure, along the short axis of the extended reflection nebulosity. Long term pho tometry reveals that the star increased in temperature until the mid -nineties, after which the photospheric flux in the optical levelled off. As the photometric changes are mostly probed in the red, they do not tra ...
The chemical history of molecules in circumstellar disks I: Ices
... chemical evolution from the pre-stellar core to the protostar and circumstellar disk. The model computes infall trajectories from any point in the cloud core and tracks the radial and vertical motion of material in the viscously evolving disk. It includes a full time-dependent radiative transfer tre ...
... chemical evolution from the pre-stellar core to the protostar and circumstellar disk. The model computes infall trajectories from any point in the cloud core and tracks the radial and vertical motion of material in the viscously evolving disk. It includes a full time-dependent radiative transfer tre ...
In Class Activity Manual - Department of Physics and Astronomy
... Want to use cooperative learning in your classroom? Don’t know how to start? Well, start here with the Interactive Lesson Guide™! These cooperative learning activities were developed for an introductory astronomy course at the University of New Mexico. I encountered many issues that are probably sim ...
... Want to use cooperative learning in your classroom? Don’t know how to start? Well, start here with the Interactive Lesson Guide™! These cooperative learning activities were developed for an introductory astronomy course at the University of New Mexico. I encountered many issues that are probably sim ...
But Still, It Moves: Tides, Stellar Parallax, and Galileo`s
... Galileo could detect variations of this value, calculations like those in the previous footnote show that Galileo could detect relative changes in their separation owing to parallax if Mizar B were 2.2% farther from the Earth than Mizar A. If, however, Galileo could detect relative changes comparabl ...
... Galileo could detect variations of this value, calculations like those in the previous footnote show that Galileo could detect relative changes in their separation owing to parallax if Mizar B were 2.2% farther from the Earth than Mizar A. If, however, Galileo could detect relative changes comparabl ...
SPIRAL STRUCTURE IN THE OUTER GALACTIC
... the Galaxy have been carried out by May et al. (1997) for d 2 kpc, and more recently by May et al. (2007) for R 14:5 kpc. The former data set was obtained completely with the CfA-Chile 1.2 m millimeter-wave telescope at Cerro Tololo; the latter one includes observations at higher resolution and ...
... the Galaxy have been carried out by May et al. (1997) for d 2 kpc, and more recently by May et al. (2007) for R 14:5 kpc. The former data set was obtained completely with the CfA-Chile 1.2 m millimeter-wave telescope at Cerro Tololo; the latter one includes observations at higher resolution and ...
Direct Imaging of Exoplanets - American Museum of Natural History
... fainter were it not for their youth and consequent internal heat sources, putting their effective temperatures in the 1000 K regime (section 1.3). Marois et al. used the groundbased Gemini and Keck telescopes for these observations. Their techniques included minimizing diffraction using ADI, and min ...
... fainter were it not for their youth and consequent internal heat sources, putting their effective temperatures in the 1000 K regime (section 1.3). Marois et al. used the groundbased Gemini and Keck telescopes for these observations. Their techniques included minimizing diffraction using ADI, and min ...
Project Description - SDSS-III
... into dark-time (moonless) and bright-time surveys. The main dark-time survey, which takes five years, is a precision measurement of the cosmic distance scale and the effects of dark energy (BOSS). The first year of dark time will be devoted to a spectroscopic study of the structure and chemical evol ...
... into dark-time (moonless) and bright-time surveys. The main dark-time survey, which takes five years, is a precision measurement of the cosmic distance scale and the effects of dark energy (BOSS). The first year of dark time will be devoted to a spectroscopic study of the structure and chemical evol ...
R136a1
RMC 136a1 (usually abbreviated to R136a1) is a Wolf-Rayet star located at the center of R136, the central condensation of stars of the large NGC 2070 open cluster in the Tarantula Nebula. It lies at a distance of about 50 kiloparsecs (163,000 light-years) in the Large Magellanic Cloud. It has the highest mass and luminosity of any known star, at 265 M☉ and 8.7 million L☉, and also one of the hottest at over 50,000 K.