Open clusters and associations in the Gaia era
... an issue if the survey does not extend beyond the cluster tidal radius, especially if there is mass segregation as the incompleteness level will then depend on mass. Moreover, objects might be missed around bright stars due to contrast issue, in crowded regions or in area with high extinction. As fo ...
... an issue if the survey does not extend beyond the cluster tidal radius, especially if there is mass segregation as the incompleteness level will then depend on mass. Moreover, objects might be missed around bright stars due to contrast issue, in crowded regions or in area with high extinction. As fo ...
Article PDF - IOPscience
... Currently available evidence suggests that star formation continued much longer in many dwarf spheroidals than it did in the main body of the Galactic halo. It is suggested that ““ young ÏÏ globular clusters, such as Ruprecht 106, might have formed in now defunct dwarf spheroidals. Assuming SagDIG, ...
... Currently available evidence suggests that star formation continued much longer in many dwarf spheroidals than it did in the main body of the Galactic halo. It is suggested that ““ young ÏÏ globular clusters, such as Ruprecht 106, might have formed in now defunct dwarf spheroidals. Assuming SagDIG, ...
Cosmic variance in [O/Fe] in the Galactic disk
... of stars to the interstellar medium (ISM). At a given location within a galaxy, slower supernova (or star formation) rates and higher variance in the yields from different stars will contribute to higher cosmic variance in chemical abundances. If two metals are produced in the same proportions in su ...
... of stars to the interstellar medium (ISM). At a given location within a galaxy, slower supernova (or star formation) rates and higher variance in the yields from different stars will contribute to higher cosmic variance in chemical abundances. If two metals are produced in the same proportions in su ...
Deep Chandra Observations of the Arches and Quintuplet Clusters at... Hui Dong Q. Daniel Wang ( &
... at energies ≤ 4 keV. The remaining diffuse emission can be characterized by a plasma with a temperature of ∼ 5 × 107 K. The 0.3-8 keV luminosity of the emission is 1.6×1033 ergs s−1 for Quintuplet and 7.7×1033 ergs s−1 for Arches. The luminosity, spectrum, and radial surface brightness are consisten ...
... at energies ≤ 4 keV. The remaining diffuse emission can be characterized by a plasma with a temperature of ∼ 5 × 107 K. The 0.3-8 keV luminosity of the emission is 1.6×1033 ergs s−1 for Quintuplet and 7.7×1033 ergs s−1 for Arches. The luminosity, spectrum, and radial surface brightness are consisten ...
PoS(EVN 2014)058 - Proceeding of science
... The aim of this project is to exploit the high-resolution capability and tremendous sensitivity of eMERLIN to assemble the most substantial radio dataset of an important massive stellar population within our Galaxy. COBRaS will produce extensive radio mapping of the OB rich stellar cluster at both C ...
... The aim of this project is to exploit the high-resolution capability and tremendous sensitivity of eMERLIN to assemble the most substantial radio dataset of an important massive stellar population within our Galaxy. COBRaS will produce extensive radio mapping of the OB rich stellar cluster at both C ...
The physics and modes of star cluster formation: observations
... William Herschel first considered this problem in the pages of these Transactions when he speculated on the origin of the clusters Messier 80 and Messier 4 in Ophiuchus (Herschel 1785). More than two centuries later, despite profound advances in astronomical science, we find that the question of the p ...
... William Herschel first considered this problem in the pages of these Transactions when he speculated on the origin of the clusters Messier 80 and Messier 4 in Ophiuchus (Herschel 1785). More than two centuries later, despite profound advances in astronomical science, we find that the question of the p ...
Our galaxy - School of Physics
... These could be the result of recent activity of the central black hole, some time in the past few million years. ...
... These could be the result of recent activity of the central black hole, some time in the past few million years. ...
Ferraro et al. 2006
... • This remote objetc (d=81Kpc; Harris et al. 1997) is one of the most lominous globular cluster (MV= −9.4; see Bellazzini 2007) similar to OmegaCen • Given its high luminosity (Mv=-9.4) and and half-mass radius (rh=25pc; Bellazzini 2007) NGC2419 lies (together with OmegaCen) Ripepi et al. 2007 in th ...
... • This remote objetc (d=81Kpc; Harris et al. 1997) is one of the most lominous globular cluster (MV= −9.4; see Bellazzini 2007) similar to OmegaCen • Given its high luminosity (Mv=-9.4) and and half-mass radius (rh=25pc; Bellazzini 2007) NGC2419 lies (together with OmegaCen) Ripepi et al. 2007 in th ...
Module 4.1 - The Scale of the Universe [slide 1] We now turn to
... to distances to pulsating stars: Cepheids and so called RR-Lyrae Stars, which are a key step in the measurements of the Hubble Constant. But notice that several steps precede this. With those, we can measure distances to a number of nearby galaxies. And then we can calibrate distance indicator relat ...
... to distances to pulsating stars: Cepheids and so called RR-Lyrae Stars, which are a key step in the measurements of the Hubble Constant. But notice that several steps precede this. With those, we can measure distances to a number of nearby galaxies. And then we can calibrate distance indicator relat ...
Open clusters in the Third Galactic Quadrant III. Alleged binary
... groups at different distances: Haffner 18(1) at 4.5 kpc and Haffner 18(2) between 9.5 and 11.4 kpc from the Sun. The derived distances and ages have been used to situate the clusters in the Galactic context. In particular, young stellar groups trace spiral structure at large Galactocentric radii. At le ...
... groups at different distances: Haffner 18(1) at 4.5 kpc and Haffner 18(2) between 9.5 and 11.4 kpc from the Sun. The derived distances and ages have been used to situate the clusters in the Galactic context. In particular, young stellar groups trace spiral structure at large Galactocentric radii. At le ...
... 3. THE RR LYRAE STARS IN M15 In Clement’s (2002) data base of variables stars, a total of 158 variable stars are known, from which approximately 104 are RR Lyrae type stars. In this work, 33 known RR Lyrae stars, identified in Figs. 1 and 2 and listed in Table 4, have been studied. For all the stars ...
Lecture-25 Notes - Georgia Southern University Astrophysics
... These massive galaxies (and their super-massive black holes) had formed before the universe was 1-billion years old!! A z = 7.1 QSO has recently been discovered. It formed ~300-million years after the creation of the universe!! ...
... These massive galaxies (and their super-massive black holes) had formed before the universe was 1-billion years old!! A z = 7.1 QSO has recently been discovered. It formed ~300-million years after the creation of the universe!! ...
Lectures 19-20 The Milky Way Galaxy
... In 1780 William Herschel produced the map below by counting stars in different directions. He concluded that the Sun is near the center of the Galaxy, and that the dimensions along the plane were five times greater than the vertical thickness. Herschel assumed (1) all stars have same luminosity (Abs ...
... In 1780 William Herschel produced the map below by counting stars in different directions. He concluded that the Sun is near the center of the Galaxy, and that the dimensions along the plane were five times greater than the vertical thickness. Herschel assumed (1) all stars have same luminosity (Abs ...
WORD - Astrophysics
... galaxies that is even reasonably representative. Indeed, even with space telescopes and the current generation of 8-10m telescopes, it is a challenge to obtain data of relevance to the evolution of the LG. With adaptive optics (AO), current 8-10m telescopes do allow evolutionary studies of LG galaxi ...
... galaxies that is even reasonably representative. Indeed, even with space telescopes and the current generation of 8-10m telescopes, it is a challenge to obtain data of relevance to the evolution of the LG. With adaptive optics (AO), current 8-10m telescopes do allow evolutionary studies of LG galaxi ...
Candidate star clusters toward the inner Milky Way discovered on
... appears to be some clustering: VVV CC 169 and VVV CC 170 have projected on-sky separation of ∼2 arcmin, but these objects have different extinctions and distances (Table 1), so it is unlikely that they are physically connected. A physical connection between VVV CC 168 and VVV CC 169, separated by ∼9 ...
... appears to be some clustering: VVV CC 169 and VVV CC 170 have projected on-sky separation of ∼2 arcmin, but these objects have different extinctions and distances (Table 1), so it is unlikely that they are physically connected. A physical connection between VVV CC 168 and VVV CC 169, separated by ∼9 ...
The self-enrichment of galactic halo globular clusters: a clue to their
... that have been used against the hypothesis of GC selfenrichment. In this first paper, we tackle the questions of the supernova energetics and of the narowness of GC red giant branch. Dopita and Smith (1986) have already addressed the first point from a purely dynamical point of view. In their model, ...
... that have been used against the hypothesis of GC selfenrichment. In this first paper, we tackle the questions of the supernova energetics and of the narowness of GC red giant branch. Dopita and Smith (1986) have already addressed the first point from a purely dynamical point of view. In their model, ...
chapter 24 instructor notes
... In 1837 Argelander, of the Bonn Observatory and orginator of the BD catalogue, was able to derive an apex for the solar motion from studying stellar proper motions. His result is very similar to that recognized today. Also in 1837, Frederick Struve found evidence for interstellar extinction in star ...
... In 1837 Argelander, of the Bonn Observatory and orginator of the BD catalogue, was able to derive an apex for the solar motion from studying stellar proper motions. His result is very similar to that recognized today. Also in 1837, Frederick Struve found evidence for interstellar extinction in star ...
Moitinho et al. - Wiley Online Library
... (Martı́nez-Delgado et al. 2005). The youth of the BP also explains why no 1–2 Gyr red clump is evident at 8 kpc. Fig. 2 also reveals the presence of a few other BPs. These would also be considered a non-Galactic population, but in this case they are much closer than the proposed distance to the CMa ...
... (Martı́nez-Delgado et al. 2005). The youth of the BP also explains why no 1–2 Gyr red clump is evident at 8 kpc. Fig. 2 also reveals the presence of a few other BPs. These would also be considered a non-Galactic population, but in this case they are much closer than the proposed distance to the CMa ...
MESSIER - EarthLink
... His first own deep sky discovery of globular cluster M3, cataloged on May 3, probably causes him to undertake a systematical search for nebulous objects, leading to the observation and recording of the objects M3-M40, many of which were own discoveries, but several from old catalogs. Messier was mad ...
... His first own deep sky discovery of globular cluster M3, cataloged on May 3, probably causes him to undertake a systematical search for nebulous objects, leading to the observation and recording of the objects M3-M40, many of which were own discoveries, but several from old catalogs. Messier was mad ...
The HERMES GALAH survey: overview
... of the Aquarius stream are in the same part of the distribution as the globular cluster stars. galaxies. The distribution of their stars in the [X/Fe]–[Fe/H] plane is well defined for an individual galaxy but di↵ers in structure from galaxy to galaxy, depending on their star formation history. (Here ...
... of the Aquarius stream are in the same part of the distribution as the globular cluster stars. galaxies. The distribution of their stars in the [X/Fe]–[Fe/H] plane is well defined for an individual galaxy but di↵ers in structure from galaxy to galaxy, depending on their star formation history. (Here ...
Spiral structure of the Third Galactic Quadrant and the solution to the
... With these results in mind, we can address the CMa overdensity. Although there is no consensus about the exact centre of the overdensity, it is generally accepted that it is around l = 240o , b = −7o . From Fig. 2 it is readily seen, both in the gas and in the clusters, that this is the approximate ...
... With these results in mind, we can address the CMa overdensity. Although there is no consensus about the exact centre of the overdensity, it is generally accepted that it is around l = 240o , b = −7o . From Fig. 2 it is readily seen, both in the gas and in the clusters, that this is the approximate ...
hr diagrams of star clusters
... Star clusters are groups of stars which, astronomers believe, were born together at roughly the same time from the same cloud of interstellar gas. HR diagrams are particularly useful for studying the characteristics of such clusters. The stars in a cluster have a range of stellar masses, from very m ...
... Star clusters are groups of stars which, astronomers believe, were born together at roughly the same time from the same cloud of interstellar gas. HR diagrams are particularly useful for studying the characteristics of such clusters. The stars in a cluster have a range of stellar masses, from very m ...
HR DIAGRAMS OF STAR CLUSTERS
... Star clusters are groups of stars which, astronomers believe, were born together at roughly the same time from the same cloud of interstellar gas. HR diagrams are particularly useful for studying the characteristics of such clusters. The stars in a cluster have a range of stellar masses, from very m ...
... Star clusters are groups of stars which, astronomers believe, were born together at roughly the same time from the same cloud of interstellar gas. HR diagrams are particularly useful for studying the characteristics of such clusters. The stars in a cluster have a range of stellar masses, from very m ...
THE PERIOD OF ROTATION OF THE SUN
... Star clusters are groups of stars which, astronomers believe, were born together at roughly the same time from the same cloud of interstellar gas. HR diagrams are particularly useful for studying the characteristics of such clusters. The stars in a cluster have a range of stellar masses, from very m ...
... Star clusters are groups of stars which, astronomers believe, were born together at roughly the same time from the same cloud of interstellar gas. HR diagrams are particularly useful for studying the characteristics of such clusters. The stars in a cluster have a range of stellar masses, from very m ...
Chapter 16 - Astronomy
... 4. We now know the nature of our Galaxy and other galaxies is closer to Curtis’ explanation. Shapley had made use of some incorrect data and misinterpreted observations of Cepheid variables because it was not known at the time that there were different types. Shapley was more correct in his ideas ab ...
... 4. We now know the nature of our Galaxy and other galaxies is closer to Curtis’ explanation. Shapley had made use of some incorrect data and misinterpreted observations of Cepheid variables because it was not known at the time that there were different types. Shapley was more correct in his ideas ab ...
Globular cluster
A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite. Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers. The name of this category of star cluster is derived from the Latin globulus—a small sphere. A globular cluster is sometimes known more simply as a globular.Globular clusters, which are found in the halo of a galaxy, contain considerably more stars and are much older than the less dense galactic, or open clusters, which are found in the disk. Globular clusters are fairly common; there are about 150 to 158 currently known globular clusters in the Milky Way, with perhaps 10 to 20 more still undiscovered. These globular clusters orbit the Galaxy at radii of 40 kiloparsecs (130,000 light-years) or more. Larger galaxies can have more: Andromeda, for instance, may have as many as 500. Some giant elliptical galaxies, particularly those at the centers of galaxy clusters, such as M87, have as many as 13,000 globular clusters.Every galaxy of sufficient mass in the Local Group has an associated group of globular clusters, and almost every large galaxy surveyed has been found to possess a system of globular clusters. The Sagittarius Dwarf galaxy and the disputed Canis Major Dwarf galaxy appear to be in the process of donating their associated globular clusters (such as Palomar 12) to the Milky Way. This demonstrates how many of this galaxy's globular clusters might have been acquired in the past.Although it appears that globular clusters contain some of the first stars to be produced in the galaxy, their origins and their role in galactic evolution are still unclear. It does appear clear that globular clusters are significantly different from dwarf elliptical galaxies and were formed as part of the star formation of the parent galaxy rather than as a separate galaxy. However, recent conjectures by astronomers suggest that globular clusters and dwarf spheroidals may not be clearly separate and distinct types of objects.