Hunting for Substructure in the Milky Way
... direction of the North Galactic Pole. In order to conserve angular momentum, over time this orbit remains approximately circular. Astronomers measure the velocity and distances of stars to analyse the angular momentum, and from this they can determine how circular the orbit of each star is. In previ ...
... direction of the North Galactic Pole. In order to conserve angular momentum, over time this orbit remains approximately circular. Astronomers measure the velocity and distances of stars to analyse the angular momentum, and from this they can determine how circular the orbit of each star is. In previ ...
A spectroscopic investigation of the O-type star - ORBi
... Context. Establishing the multiplicity of O-type stars is the first step towards accurately determining their stellar parameters. Moreover, the distribution of the orbital parameters provides observational clues to the way that O-type stars form and to the interactions during their evolution. Aims. ...
... Context. Establishing the multiplicity of O-type stars is the first step towards accurately determining their stellar parameters. Moreover, the distribution of the orbital parameters provides observational clues to the way that O-type stars form and to the interactions during their evolution. Aims. ...
Binarity in carbon-enhanced metal-poor stars
... Pb absorption lines are very weak and the strongest line in the optical overlaps with the CH feature, this hypothesis is difficult to test, especially in C-rich stars. A robust upper limit could nonetheless be given for the brightest CEMP-no star, BD +44-493, which did not show the predicted overabu ...
... Pb absorption lines are very weak and the strongest line in the optical overlaps with the CH feature, this hypothesis is difficult to test, especially in C-rich stars. A robust upper limit could nonetheless be given for the brightest CEMP-no star, BD +44-493, which did not show the predicted overabu ...
diy astronomy - American Museum of Natural History
... Astronomical data are archived in large on-line databases; real images of any part of the sky can be easily obtained from the Internet. • Astrometry is a technique that astronomers use to measure the position or change in position of objects in the sky. They can use it to calculate how fast stars m ...
... Astronomical data are archived in large on-line databases; real images of any part of the sky can be easily obtained from the Internet. • Astrometry is a technique that astronomers use to measure the position or change in position of objects in the sky. They can use it to calculate how fast stars m ...
A spectroscopic investigation of the O
... Moreover, the distribution of the orbital parameters provides observational clues to the way that O-type stars form and to the interactions during their evolution. Aims. Our objective is to constrain the multiplicity of a sample of O-type stars belonging to poorly investigated OB associations in the ...
... Moreover, the distribution of the orbital parameters provides observational clues to the way that O-type stars form and to the interactions during their evolution. Aims. Our objective is to constrain the multiplicity of a sample of O-type stars belonging to poorly investigated OB associations in the ...
Mn, Cu, and Zn abundances in barium stars and their correlations
... intermediate mass AGB stars, and the weak component of the s-process, thought to be sited at He-burning cores of M ≥ 10 M stars (see Raiteri et al. 1993; Matteucci et al. 1993; Mishenina et al. 2002, and references therein). Even though their positions in the periodic table are contiguous, their be ...
... intermediate mass AGB stars, and the weak component of the s-process, thought to be sited at He-burning cores of M ≥ 10 M stars (see Raiteri et al. 1993; Matteucci et al. 1993; Mishenina et al. 2002, and references therein). Even though their positions in the periodic table are contiguous, their be ...
On the nature of sn stars. I. A detailed abundance study
... that all sn stars were in fact related to CP stars and search for common features in their abundance values. A possible sn-CP relation would indicate that the sn characteristics are present in those atmospheres with the physical conditions required by the diffusion to work efficiently. Also we would ...
... that all sn stars were in fact related to CP stars and search for common features in their abundance values. A possible sn-CP relation would indicate that the sn characteristics are present in those atmospheres with the physical conditions required by the diffusion to work efficiently. Also we would ...
neutron star
... galaxies are richer in heavy elements than the Sun, with the highest abundances ever seen in the early Universe. Heavy elements that enrich mature galaxies in the local Universe were made in past generations of stars. So these young galaxies have experienced a prodigious rate of star formation and c ...
... galaxies are richer in heavy elements than the Sun, with the highest abundances ever seen in the early Universe. Heavy elements that enrich mature galaxies in the local Universe were made in past generations of stars. So these young galaxies have experienced a prodigious rate of star formation and c ...
Astronomy Astrophysics Detailed abundances of a large sample of giant stars in... and in the Sagittarius nucleus
... of the coolest stars (see Fig. 3) in the latter component are heavily affected by titanium oxide (TiO) bands, which severely depress the continuum, in particular in the HR13 spectral range. They were omitted from further analysis. After the first abundance analysis, we found that three stars, attribu ...
... of the coolest stars (see Fig. 3) in the latter component are heavily affected by titanium oxide (TiO) bands, which severely depress the continuum, in particular in the HR13 spectral range. They were omitted from further analysis. After the first abundance analysis, we found that three stars, attribu ...
Conference Abstract Booklet here.
... the Hubble Source Catalog (HSC) which includes 107 objects detected with WFPC2, ACS, and WFC3 instruments in at least one visit. The lightcurves extracted from the HSC are corrected for systematic effects by applying local zero-point corrections and are screened for bad measurements. For each lightc ...
... the Hubble Source Catalog (HSC) which includes 107 objects detected with WFPC2, ACS, and WFC3 instruments in at least one visit. The lightcurves extracted from the HSC are corrected for systematic effects by applying local zero-point corrections and are screened for bad measurements. For each lightc ...
Carbon-enhanced metal-poor stars in dwarf galaxies
... (2007) to identify CEMP stars1 .However, the carbon-excess is small and the errors big, making this classification very uncertain. Thus, the only reliable CEMPno star discovered in Sculptor, [C/Fe]= 1.01 ± 0.1, has an unusually high ironabundance, [Fe/H]≈ −2 (Skúladóttir et al. 2015), which makes th ...
... (2007) to identify CEMP stars1 .However, the carbon-excess is small and the errors big, making this classification very uncertain. Thus, the only reliable CEMPno star discovered in Sculptor, [C/Fe]= 1.01 ± 0.1, has an unusually high ironabundance, [Fe/H]≈ −2 (Skúladóttir et al. 2015), which makes th ...
Abstract book
... Title: Density or mass, which control the early stages of the star formation process? Abstract. How do stellar clusters form is a one of the key questions for understanding the physical mechanisms that drive the transformation of cold molecular gas into stars in different environments. In particular ...
... Title: Density or mass, which control the early stages of the star formation process? Abstract. How do stellar clusters form is a one of the key questions for understanding the physical mechanisms that drive the transformation of cold molecular gas into stars in different environments. In particular ...
Spectral Matching for Elemental Abundances of Evolved Stars of Globular Clusters
... used to estimate the oxygen abundance of the stars, leading to a determination of whether a particular star was oxygen-rich or oxygen-poor. From this a catalogue of abundances of iron, carbon and barium of 848 giant branch stars were determined, of which 557 also had well-defined nitrogen abundances ...
... used to estimate the oxygen abundance of the stars, leading to a determination of whether a particular star was oxygen-rich or oxygen-poor. From this a catalogue of abundances of iron, carbon and barium of 848 giant branch stars were determined, of which 557 also had well-defined nitrogen abundances ...
Hot subdwarf stars-galactic orbits and distribution perpendicular to
... (small) sample had disk orbits but 1 star had an orbit with z-distance maxima ranging from 8 to 20 kpc. Evidence for more stars with halo orbits was given by de Boer et al. (1995). We have investigated 41 stars for their kinematic behaviour. The choice of stars was solely determined by the availabil ...
... (small) sample had disk orbits but 1 star had an orbit with z-distance maxima ranging from 8 to 20 kpc. Evidence for more stars with halo orbits was given by de Boer et al. (1995). We have investigated 41 stars for their kinematic behaviour. The choice of stars was solely determined by the availabil ...
Abstracts - Physics of Evolved Stars 2015
... The Molspheres of Mira Variables, K. Hinkle [et al.] ............................................................................77 Polarization Signatures of Stellar Bow Shocks, M. Shrestha [et al.] .....................................................78 Mapping the Central Region of the PPN CRL 61 ...
... The Molspheres of Mira Variables, K. Hinkle [et al.] ............................................................................77 Polarization Signatures of Stellar Bow Shocks, M. Shrestha [et al.] .....................................................78 Mapping the Central Region of the PPN CRL 61 ...
The Norma cluster (ACO3627) – II. The near-infrared Ks
... seem to have a steeper bright end than those without cD galaxies. Often the brightest galaxy is excluded to obtain a better fit, particularly in cD clusters. The Schechter parameters have also been found to vary depending on the region sampled within the cluster, the size of the area and the limitin ...
... seem to have a steeper bright end than those without cD galaxies. Often the brightest galaxy is excluded to obtain a better fit, particularly in cD clusters. The Schechter parameters have also been found to vary depending on the region sampled within the cluster, the size of the area and the limitin ...
Cycles of magnetic activity in solar-type stars. The place of the Sun
... on the Hertzsprung-Russell diagram. Stars which are close to the ZAMS in Figure 1 have the lowest age among all other stars: log(Age/yr) is about 8 - 8.5. The older the star is, the farther it is from the ZAMS. Ages of stars in the Figure 1 varies from 108 to 1010 years. We can also see that some st ...
... on the Hertzsprung-Russell diagram. Stars which are close to the ZAMS in Figure 1 have the lowest age among all other stars: log(Age/yr) is about 8 - 8.5. The older the star is, the farther it is from the ZAMS. Ages of stars in the Figure 1 varies from 108 to 1010 years. We can also see that some st ...
Rocky planetesimals as the origin of metals in DZ stars
... obvious pattern is seen, although there may be a higher density of DZA stars near the Galactic disc and perhaps also towards more modest speeds, but the former may be an observational bias due to diminished spectroscopic sensitivity. In any case, one should expect a correlation between these quantit ...
... obvious pattern is seen, although there may be a higher density of DZA stars near the Galactic disc and perhaps also towards more modest speeds, but the former may be an observational bias due to diminished spectroscopic sensitivity. In any case, one should expect a correlation between these quantit ...
Chemical analysis of 24 dusty (pre-) main
... Despite the broad wavelength coverage, for several program stars only a few lines turned out to be appropriate for detailed abundance analyses. Such a circumstance is not unusual for A/B-type stars, where the condition that spectral lines with equivalent widths higher than 150 mÅ should be avoided i ...
... Despite the broad wavelength coverage, for several program stars only a few lines turned out to be appropriate for detailed abundance analyses. Such a circumstance is not unusual for A/B-type stars, where the condition that spectral lines with equivalent widths higher than 150 mÅ should be avoided i ...
Galaxy Sorting
... gas and dust fill the disks of spiral galaxies, and new star formation continues to take place in their disks. Irregular galaxies appear chaotic, and often have many bright, young stars, the result of recent bursts of intense star formation. For many years, astronomers thought the dissimilarities ...
... gas and dust fill the disks of spiral galaxies, and new star formation continues to take place in their disks. Irregular galaxies appear chaotic, and often have many bright, young stars, the result of recent bursts of intense star formation. For many years, astronomers thought the dissimilarities ...
FIRST STELLAR ABUNDANCES IN THE DWARF IRREGULAR
... 2002. For the best candidates, the ESI low-resolution spectra were complemented by high-resolution spectra taken with UVES in the April 2002 visitor run. All candidates stars were first checked for their membership to the Sextans A galaxy by comparing the measured radial velocities of the stars to t ...
... 2002. For the best candidates, the ESI low-resolution spectra were complemented by high-resolution spectra taken with UVES in the April 2002 visitor run. All candidates stars were first checked for their membership to the Sextans A galaxy by comparing the measured radial velocities of the stars to t ...
Classification of Variable Stars
... exhausted. (i.e. V746 Oph is the 746th variable to be discovered in Ophiuchus.) Variable star names are determined by a committee appointed by the International Astronomical Union (I.A.U.). The assignments are made in the order in which the variable stars were discovered in a constellation. If one o ...
... exhausted. (i.e. V746 Oph is the 746th variable to be discovered in Ophiuchus.) Variable star names are determined by a committee appointed by the International Astronomical Union (I.A.U.). The assignments are made in the order in which the variable stars were discovered in a constellation. If one o ...
Corona Australis
Corona Australis /kɵˈroʊnə ɒˈstreɪlɨs/ or Corona Austrina /kɵˈroʊnə ɒˈstraɪnə/ is a constellation in the Southern Celestial Hemisphere. Its Latin name means ""southern crown"", and it is the southern counterpart of Corona Borealis, the northern crown. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the 88 modern constellations. The Ancient Greeks saw Corona Australis as a wreath rather than a crown and associated it with Sagittarius or Centaurus. Other cultures have likened the pattern to a turtle, ostrich nest, a tent, or even a hut belonging to a rock hyrax.Although fainter than its namesake, the oval- or horseshoe-shaped pattern of its brighter stars renders it distinctive. Alpha and Beta Coronae Australis are the two brightest stars with an apparent magnitude of around 4.1. Epsilon Coronae Australis is the brightest example of a W Ursae Majoris variable in the southern sky. Lying alongside the Milky Way, Corona Australis contains one of the closest star-forming regions to our Solar System—a dusty dark nebula known as the Corona Australis Molecular Cloud, lying about 430 light years away. Within it are stars at the earliest stages of their lifespan. The variable stars R and TY Coronae Australis light up parts of the nebula, which varies in brightness accordingly.