THE STAR FORMATION AND NUCLEAR ACCRETION HISTORIES OF NORMAL GALAXIES
... using Hectospec, a robotic 300 fiber spectrograph for the MMT (Fabricant et al. 1998, Roll et al. 1998, Fabricant et al. 2005) and are 95% complete for R < 19.2; our analysis is not significantly affected by the modest level of incompleteness. Although we have redshifts for roughly half of the remai ...
... using Hectospec, a robotic 300 fiber spectrograph for the MMT (Fabricant et al. 1998, Roll et al. 1998, Fabricant et al. 2005) and are 95% complete for R < 19.2; our analysis is not significantly affected by the modest level of incompleteness. Although we have redshifts for roughly half of the remai ...
The low-mass dispersed population around the Lupus clouds
... the numerous members already known from previous studies. The new members are mainly located in a distributed population, projected at large angular distances from the main dark clouds where the most recent star formation is taking place at present. Indications were also discussed of a similar popul ...
... the numerous members already known from previous studies. The new members are mainly located in a distributed population, projected at large angular distances from the main dark clouds where the most recent star formation is taking place at present. Indications were also discussed of a similar popul ...
THE VELOCITY DISTRIBUTION OF THE NEAREST
... unsuitable since they vary between species. Note that since we are interested in the distribution of the deviation of component velocities in the rest frame of V flow , the component data set includes all measured components for each star. We find that this procedure yields a predicted flow velocity V ...
... unsuitable since they vary between species. Note that since we are interested in the distribution of the deviation of component velocities in the rest frame of V flow , the component data set includes all measured components for each star. We find that this procedure yields a predicted flow velocity V ...
9 The Clearing of Protoplanetary Disks and of the Protosolar Nebula
... observed in L-band, out to about 1 AU from T Tauri stars. Fig. 9.2 shows the fraction of T Tauri stars (mostly K and M stars) with IR excess at IRAC wavelengths (3.6, 4.5, 5.8, and 8µm, full circles). In addition to the data (and references) presented in Hernández et al. (2008) we have included the ...
... observed in L-band, out to about 1 AU from T Tauri stars. Fig. 9.2 shows the fraction of T Tauri stars (mostly K and M stars) with IR excess at IRAC wavelengths (3.6, 4.5, 5.8, and 8µm, full circles). In addition to the data (and references) presented in Hernández et al. (2008) we have included the ...
Submm Observations of Massive Star Formation in the Giant
... Aims. This dissertation focuses on the detailed study of the region NGC 6334, located in the Galaxy at a distance of 1.7 kpc. It is aimed to trace the gas velocities in the filamentary, massive star-forming region NGC 6334 at several scales and to explain its dynamics. For that purpose, different sc ...
... Aims. This dissertation focuses on the detailed study of the region NGC 6334, located in the Galaxy at a distance of 1.7 kpc. It is aimed to trace the gas velocities in the filamentary, massive star-forming region NGC 6334 at several scales and to explain its dynamics. For that purpose, different sc ...
Astrometric accuracy during the past 2000 years
... detailed comparisons, but it is difficult in many cases, if at all possible, to find sufficient information about this matter, and it cannot easily be presented in one line of a table. Internal errors are sometimes placed in brackets. The standard errors in the tables are sufficient for the original ...
... detailed comparisons, but it is difficult in many cases, if at all possible, to find sufficient information about this matter, and it cannot easily be presented in one line of a table. Internal errors are sometimes placed in brackets. The standard errors in the tables are sufficient for the original ...
Confirmation of Hostless Type Ia Supernovae Using Hubble Space
... We present deep Hubble Space Telescope imaging at the locations of four, potentially hostless, long-faded Type Ia supernovae (SNe Ia) in low-redshift, rich galaxy clusters that were identified in the Multi-Epoch Nearby Cluster Survey. Assuming a steep faint-end slope for the galaxy cluster luminosit ...
... We present deep Hubble Space Telescope imaging at the locations of four, potentially hostless, long-faded Type Ia supernovae (SNe Ia) in low-redshift, rich galaxy clusters that were identified in the Multi-Epoch Nearby Cluster Survey. Assuming a steep faint-end slope for the galaxy cluster luminosit ...
BLANCO CARDENAS
... antigua casera Sharo. A aquellos que se fueron de Granada hace un tiempo, estoy feliz de que sean piezas de este rompecabezas con la Alhambra de fondo: gracias Juliane Serres, Ana Victoria Cuesta, Sebastian “Chingue” Meier, Lucı́a Piñeiro Freire, Lizette Duque, Ana Marı́a Salazar; sigo recordándol ...
... antigua casera Sharo. A aquellos que se fueron de Granada hace un tiempo, estoy feliz de que sean piezas de este rompecabezas con la Alhambra de fondo: gracias Juliane Serres, Ana Victoria Cuesta, Sebastian “Chingue” Meier, Lucı́a Piñeiro Freire, Lizette Duque, Ana Marı́a Salazar; sigo recordándol ...
Classification of Variable Stars
... V1668 Cyg. These are stars in constellations for which all of the letter combinations have been 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 assignment ...
... V1668 Cyg. These are stars in constellations for which all of the letter combinations have been 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 assignment ...
20. Meteorites and the chemical evolution of the Milky Way
... and metallicity. Moreover, there are still large uncertainties in the predicted yields due to uncertainties in the stellar evolution physics and nuclear reaction cross sections. A key concept related to stellar yields is the definition of primary and secondary species. A primary specie is one that c ...
... and metallicity. Moreover, there are still large uncertainties in the predicted yields due to uncertainties in the stellar evolution physics and nuclear reaction cross sections. A key concept related to stellar yields is the definition of primary and secondary species. A primary specie is one that c ...
Chapter 15 Stars, Galaxies and Universe
... • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” • To advance through the presentation, click the right-arrow key or the space bar. • From the resources slide, click on any resource to see a presentation for that resource. • From the Cha ...
... • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” • To advance through the presentation, click the right-arrow key or the space bar. • From the resources slide, click on any resource to see a presentation for that resource. • From the Cha ...
Galaxies Astronomy 1 — Elementary Astronomy LA Mission College Spring F2015
... average density ~1 atom per cc ...
... average density ~1 atom per cc ...
Ages of young stars
... (l) Cargile and James (2010), (m) Naylor et al. (2009), (n) derived by E. Mamajek using data from Hauck and Mermilliod (1998) and isochrones from Bertelli et al. (2009), (o) Ventura et al. (1998). ally negligible) and, presented separately, the systematic absolute age uncertainty estimated by Burke ...
... (l) Cargile and James (2010), (m) Naylor et al. (2009), (n) derived by E. Mamajek using data from Hauck and Mermilliod (1998) and isochrones from Bertelli et al. (2009), (o) Ventura et al. (1998). ally negligible) and, presented separately, the systematic absolute age uncertainty estimated by Burke ...
Ages of Young Stars
... (l) Cargile and James (2010), (m) Naylor et al. (2009), (n) derived by E. Mamajek using data from Hauck and Mermilliod (1998) and isochrones from Bertelli et al. (2009), (o) Ventura et al. (1998). ally negligible) and, presented separately, the systematic absolute age uncertainty estimated by Burke ...
... (l) Cargile and James (2010), (m) Naylor et al. (2009), (n) derived by E. Mamajek using data from Hauck and Mermilliod (1998) and isochrones from Bertelli et al. (2009), (o) Ventura et al. (1998). ally negligible) and, presented separately, the systematic absolute age uncertainty estimated by Burke ...
A subaru/suprime-cam wide
... (Durham, UK/Subaru Telescope, NAOJ) R. Sharples (Durham), N. Arimoto (NAOJ), M. Onodera (NAOJ / Univ. of Tokyo), K. Ohta (Kyoto Univ.), Y. Yamada (NAOJ) Subaru & ...
... (Durham, UK/Subaru Telescope, NAOJ) R. Sharples (Durham), N. Arimoto (NAOJ), M. Onodera (NAOJ / Univ. of Tokyo), K. Ohta (Kyoto Univ.), Y. Yamada (NAOJ) Subaru & ...
Chapter 20 Notes
... Studying Stars, continued • We learn about stars by studying light. • Stars produce a full range of electromagnetic radiation, from high-energy X-rays to low-energy radio waves. • Scientists use optical telescopes to study visible light and radio telescopes to study radio waves emitted from astronom ...
... Studying Stars, continued • We learn about stars by studying light. • Stars produce a full range of electromagnetic radiation, from high-energy X-rays to low-energy radio waves. • Scientists use optical telescopes to study visible light and radio telescopes to study radio waves emitted from astronom ...
CORONAL EVOLUTION OF THE SUN IN TIME: HIGH
... magnetic activity level. Whereas starspots may cover a few percent of the photosphere of the most active solar analogs, thus producing a photometric wave with a modulation depth of a few percent at best, the range of X-ray luminosity LX in a solar analog spans at least 3 orders of magnitude between ...
... magnetic activity level. Whereas starspots may cover a few percent of the photosphere of the most active solar analogs, thus producing a photometric wave with a modulation depth of a few percent at best, the range of X-ray luminosity LX in a solar analog spans at least 3 orders of magnitude between ...
Project Description - SDSS-III
... on a consistent cosmological model that incorporates cold dark matter, a baryon-to-dark-matter ratio ∼1:6, flat space, and primordial fluctuations with the statistical properties predicted by inflation. This model requires one very surprising ingredient, “dark energy,” which drives accelerating expa ...
... on a consistent cosmological model that incorporates cold dark matter, a baryon-to-dark-matter ratio ∼1:6, flat space, and primordial fluctuations with the statistical properties predicted by inflation. This model requires one very surprising ingredient, “dark energy,” which drives accelerating expa ...
Galaxies
... However, at a fundamental level we still lack a solid understanding of the basic physics of galaxy evolution. We do not know for certain that all galaxies form at peaks in the dark matter density distribution. There is considerable debate about cold versus hot accretion of gas onto dark matter halos ...
... However, at a fundamental level we still lack a solid understanding of the basic physics of galaxy evolution. We do not know for certain that all galaxies form at peaks in the dark matter density distribution. There is considerable debate about cold versus hot accretion of gas onto dark matter halos ...
Stargazing For Beginners: A Binocular Tour of the Southern Night Sky
... nebulae, and star clusters. It assumes you are equipped with nothing more than a simple pair of binoculars, and that you know nothing of astronomy or the layout of the night sky. The course is inspired by the 19th century book entitled Astronomy with an Opera Glass by Garrett Serviss, but has been c ...
... nebulae, and star clusters. It assumes you are equipped with nothing more than a simple pair of binoculars, and that you know nothing of astronomy or the layout of the night sky. The course is inspired by the 19th century book entitled Astronomy with an Opera Glass by Garrett Serviss, but has been c ...
Characterizing filaments in regions of high-mass star
... 1997), Mline,crit = 2 c2s /G ∼ 16 M /pc, where cs ∼ 0.2 km/s is the isothermal sound speed for molecular gas at T ∼ 10 K (e.g. Könyves et al. 2015). These Herschel findings support a scenario for low-mass star formation in two main steps (cf. André et al. 2014): First, large-scale compression of in ...
... 1997), Mline,crit = 2 c2s /G ∼ 16 M /pc, where cs ∼ 0.2 km/s is the isothermal sound speed for molecular gas at T ∼ 10 K (e.g. Könyves et al. 2015). These Herschel findings support a scenario for low-mass star formation in two main steps (cf. André et al. 2014): First, large-scale compression of in ...
IRC −10414: a bow-shock-producing red supergiant star
... Most runaway OB stars, like the majority of massive stars residing in their parent clusters, go through the red supergiant (RSG) phase during their lifetimes. Nonetheless, although many dozens of massive runaways were found to be associated with bow shocks, only two RSG bow-shock-producing stars, Be ...
... Most runaway OB stars, like the majority of massive stars residing in their parent clusters, go through the red supergiant (RSG) phase during their lifetimes. Nonetheless, although many dozens of massive runaways were found to be associated with bow shocks, only two RSG bow-shock-producing stars, Be ...
NGC 6231: a young open cluster under X-rays
... • The canonical relation is tightly constrained V but still not understood on firm theoretical ground ! • Our sample is inhomogeneous in terms of spectral sub-type and luminosity class same mechanism for all • Confirmed by a recent study by Anthokin et al. on Cyg OB2 • Very limited room for the B ...
... • The canonical relation is tightly constrained V but still not understood on firm theoretical ground ! • Our sample is inhomogeneous in terms of spectral sub-type and luminosity class same mechanism for all • Confirmed by a recent study by Anthokin et al. on Cyg OB2 • Very limited room for the B ...
Formation and evolution of giant molecular clouds in a barred spiral
... statistical studies of them. Our study could help to interpret the observational results. Results. The collision velocity shows a clear dependence on galactic environment (see Figure 2). Clouds formed in the bar region typically collide faster than those in the spiral. Such speeds can be unproductiv ...
... statistical studies of them. Our study could help to interpret the observational results. Results. The collision velocity shows a clear dependence on galactic environment (see Figure 2). Clouds formed in the bar region typically collide faster than those in the spiral. Such speeds can be unproductiv ...
H II region
An H II region is a large, low-density cloud of partially ionized gas in which star formation has recently taken place. The short-lived blue stars forged in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. The first known H II region was the Orion Nebula, which was discovered in 1610 by Nicolas-Claude Fabri de Peiresc.H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II, pronounced H-two by astronomers (an H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). Such regions have extremely diverse shapes, because the distribution of the stars and gas inside them is irregular. They often appear clumpy and filamentary, sometimes showing bizarre shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster of birthed stars such as the Pleiades.H II regions can be seen to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies. Spiral and irregular galaxies contain many H II regions, while elliptical galaxies are almost devoid of them. In the spiral galaxies, including the Milky Way, H II regions are concentrated in the spiral arms, while in the irregular galaxies they are distributed chaotically. Some galaxies contain huge H II regions, which may contain tens of thousands of stars. Examples include the 30 Doradus region in the Large Magellanic Cloud and NGC 604 in the Triangulum Galaxy.