harlow shapley - National Academy of Sciences
... of the stars, but Shapley from the start thought in terms of exploring the depths of the universe. He saw the eclipsing binaries as potential standard candles observable to great distances from the sun and earth. We note here that Martha Betz Shapley in later life became an experienced and expert an ...
... of the stars, but Shapley from the start thought in terms of exploring the depths of the universe. He saw the eclipsing binaries as potential standard candles observable to great distances from the sun and earth. We note here that Martha Betz Shapley in later life became an experienced and expert an ...
A Universal Stellar Initial Mass Function? A Critical Look Further
... be used to construct samples with significant numbers of high-mass stars. The volume density of stars in each sample can be appropriately normalized, but constructing one IMF from these data requires the assumption that the IMF does not vary between those two volumes. The second implicit assumption ...
... be used to construct samples with significant numbers of high-mass stars. The volume density of stars in each sample can be appropriately normalized, but constructing one IMF from these data requires the assumption that the IMF does not vary between those two volumes. The second implicit assumption ...
Report from the Subaru Telescope for External
... Observations of Lyα selected galaxies, also known as Lyα emitters (LAEs), have indicated that the Lyα luminosity functions (LFs) of LAEs do not evolve between z = 3.1 and z = 5.7. In contrast, the Lyα luminosity of LAEs does evolve at z > 6 (e.g., Ouchi et al. 2010; Kashikawa et al. 2011). This evol ...
... Observations of Lyα selected galaxies, also known as Lyα emitters (LAEs), have indicated that the Lyα luminosity functions (LFs) of LAEs do not evolve between z = 3.1 and z = 5.7. In contrast, the Lyα luminosity of LAEs does evolve at z > 6 (e.g., Ouchi et al. 2010; Kashikawa et al. 2011). This evol ...
Mid-infrared Properties of Seyfert Galaxies: the IRAS 12um Sample
... Using the infrared to study this issue offers a number of advantages the more important of which is… SHAO - Oct 2010 ...
... Using the infrared to study this issue offers a number of advantages the more important of which is… SHAO - Oct 2010 ...
Revising the census of low luminosity AGN
... A LOW EW (~1 Å) IS CHARACTERISTIC OF STELLAR PROCESSES AGN 10 - Roma 10/09/2012 ...
... A LOW EW (~1 Å) IS CHARACTERISTIC OF STELLAR PROCESSES AGN 10 - Roma 10/09/2012 ...
Hubble 2006: Science Year in Review
... web—the large-scale structure of the universe—whose form is determined by the gravity of dark matter and is traced by the spatial distribution of galaxies and intergalactic gas. WFC3 is a new camera sensitive across a wide range of wavelengths (colors), including infrared, visible, and ultraviolet l ...
... web—the large-scale structure of the universe—whose form is determined by the gravity of dark matter and is traced by the spatial distribution of galaxies and intergalactic gas. WFC3 is a new camera sensitive across a wide range of wavelengths (colors), including infrared, visible, and ultraviolet l ...
WFC3 Science White Paper - Space Telescope Science Institute
... A primary legacy of the Hubble Space Telescope (HST), both scientifically and in the public eye, will be the spectacular images it produces of the astronomical sky. Its cameras have been among the most productive instruments in the history of astronomy. As HST begins a second decade of operations, i ...
... A primary legacy of the Hubble Space Telescope (HST), both scientifically and in the public eye, will be the spectacular images it produces of the astronomical sky. Its cameras have been among the most productive instruments in the history of astronomy. As HST begins a second decade of operations, i ...
1 Globular Cluster Systems - McMaster Physics and Astronomy
... the X axis). (3) The fundamental distance scale used by Shapley { essentially, the luminosity of the RR Lyraes or the tip of the red-giant branch { was about one magnitude brighter than the value adopted today; again, the result was to overestimate distances for almost all clusters. Nevertheless, th ...
... the X axis). (3) The fundamental distance scale used by Shapley { essentially, the luminosity of the RR Lyraes or the tip of the red-giant branch { was about one magnitude brighter than the value adopted today; again, the result was to overestimate distances for almost all clusters. Nevertheless, th ...
OBSERVATIONS OF PHYSICAL PROCESSES IN
... cluster galaxies (BCGs) of those clusters. It has been known for a while that the state of the hot intracluster medium (ICM) gas in the core of a galaxy cluster, quantified as the central entropy of the gas, can be found in two particular states. Galaxy clusters with central entropies greater than 3 ...
... cluster galaxies (BCGs) of those clusters. It has been known for a while that the state of the hot intracluster medium (ICM) gas in the core of a galaxy cluster, quantified as the central entropy of the gas, can be found in two particular states. Galaxy clusters with central entropies greater than 3 ...
JENAM-2011 Book of abstracts
... probability for a massive star to become an accretion powered X-ray source once upon its lifetime. This explains the unexpectedly high contribution of accreting compact objects of stellar mass to the Cosmic X-ray background, ∼7-10%. Underneath bright X-ray binaries, unresolved emission is present in ...
... probability for a massive star to become an accretion powered X-ray source once upon its lifetime. This explains the unexpectedly high contribution of accreting compact objects of stellar mass to the Cosmic X-ray background, ∼7-10%. Underneath bright X-ray binaries, unresolved emission is present in ...
probing quasar environments with tunable filter
... During this project, I have benefited enormously from the input of not just one but two supervisors. First, many thanks are due to Joanne Baker for getting the whole thing started. Isobel Hook was generous (or foolish!) enough to take over part of the way through: her insights and advice were invalu ...
... During this project, I have benefited enormously from the input of not just one but two supervisors. First, many thanks are due to Joanne Baker for getting the whole thing started. Isobel Hook was generous (or foolish!) enough to take over part of the way through: her insights and advice were invalu ...
Gamma-Ray Bursts and Puzzles of Core
... In point of fact, this is the first result of the GRB optical identification with already known objects: GRBs are identified with ordinary (or the most numerous in the Universe at any z) galaxies up to ~28 st. magnitudes and more. The GRB hosts should not be special, but normal, faint, star-forming ...
... In point of fact, this is the first result of the GRB optical identification with already known objects: GRBs are identified with ordinary (or the most numerous in the Universe at any z) galaxies up to ~28 st. magnitudes and more. The GRB hosts should not be special, but normal, faint, star-forming ...
IRAM Annual Report 2014
... One of the challenges in understanding how stars form is how massive clouds of gas and dust fragment to produce the direct progenitors of individual stars. In order to shed new light on the formation of stars more than 10 times the mass of our Sun, an international team of astronomers led by Nicolas ...
... One of the challenges in understanding how stars form is how massive clouds of gas and dust fragment to produce the direct progenitors of individual stars. In order to shed new light on the formation of stars more than 10 times the mass of our Sun, an international team of astronomers led by Nicolas ...
Formation of Molecular Clouds and Global Conditions for Star
... 2009; Juneau et al. 2009; Garcı́a-Burillo et al. 2012) also show power-law correlations but with smaller indices; the index appears to depend mostly on the line critical density, a result that can be explained through models (Krumholz and Thompson 2007; Narayanan et al. 2008b,a). Within galaxies the ...
... 2009; Juneau et al. 2009; Garcı́a-Burillo et al. 2012) also show power-law correlations but with smaller indices; the index appears to depend mostly on the line critical density, a result that can be explained through models (Krumholz and Thompson 2007; Narayanan et al. 2008b,a). Within galaxies the ...
the stebbins galaxy: the origins of interstellar medium studies
... the Galaxy, shows the Sun to be far from that center. 2) The measured distances to globular clusters show the Galaxy to be about 70,000 parsecs (200,000 light-years or so) in diameter (Shapley, 1930a: 221). This is about twice the modern figure for the luminous Galaxy. In his earlier publications, a ...
... the Galaxy, shows the Sun to be far from that center. 2) The measured distances to globular clusters show the Galaxy to be about 70,000 parsecs (200,000 light-years or so) in diameter (Shapley, 1930a: 221). This is about twice the modern figure for the luminous Galaxy. In his earlier publications, a ...
Studies of molecular clouds at the Galactic centre Roland Karlsson DECLINATION (B1950)
... winding of the spiral arms. However, intermediate classes also occur. A socalled grand design spiral galaxy is one where the spiral arms are well-defined. It is generally assumed that a central supermassive black hole (SMBH) resides at the dynamical centre of most spiral galaxies. Galaxies are obser ...
... winding of the spiral arms. However, intermediate classes also occur. A socalled grand design spiral galaxy is one where the spiral arms are well-defined. It is generally assumed that a central supermassive black hole (SMBH) resides at the dynamical centre of most spiral galaxies. Galaxies are obser ...
DUSTiNGS III: Distribution of Intermediate
... or not stellar populations extending to the outer extremities of galaxies are purely old populations (supporting in-situ star formation in a contracting gaseous disk) or a mix of intermediate-age and old stars (supporting a combination of in-situ star formation, internal drivers of extended structur ...
... or not stellar populations extending to the outer extremities of galaxies are purely old populations (supporting in-situ star formation in a contracting gaseous disk) or a mix of intermediate-age and old stars (supporting a combination of in-situ star formation, internal drivers of extended structur ...
The Life Cycle of Stars: Supernovae in Starbursts by Jason Kezwer
... ABSTRACT We have observed the nearest ultraluminous infrared galaxy Arp 220 with a 13 month near-infrared observing program using the Canada France Hawaii Telescope to search for obscured supernovae in this extreme star forming environment. This monitoring program was aimed as a feasibility study to ...
... ABSTRACT We have observed the nearest ultraluminous infrared galaxy Arp 220 with a 13 month near-infrared observing program using the Canada France Hawaii Telescope to search for obscured supernovae in this extreme star forming environment. This monitoring program was aimed as a feasibility study to ...
Markov Chain Monte Carlo Modeling of High-Redshift Quasar
... Quasars, the visible phenomena associated with the active accretion phase of supermassive black holes found in the centers of galaxies, represent one of the most energetic processes in the Universe. As matter falls into the central black hole, it is accelerated and collisionally heated, and the radi ...
... Quasars, the visible phenomena associated with the active accretion phase of supermassive black holes found in the centers of galaxies, represent one of the most energetic processes in the Universe. As matter falls into the central black hole, it is accelerated and collisionally heated, and the radi ...
GRB prompt emission
... Hosts! • Hosts of long GRBs are star-forming galaxies • GRBs trace the stellar distribution (in distance from galaxy center) • GRBs occur in dense environments (star forming regions?) ...
... Hosts! • Hosts of long GRBs are star-forming galaxies • GRBs trace the stellar distribution (in distance from galaxy center) • GRBs occur in dense environments (star forming regions?) ...
GRB prompt emission
... Hosts! • Hosts of long GRBs are star-forming galaxies • GRBs trace the stellar distribution (in distance from galaxy center) • GRBs occur in dense environments (star forming regions?) ...
... Hosts! • Hosts of long GRBs are star-forming galaxies • GRBs trace the stellar distribution (in distance from galaxy center) • GRBs occur in dense environments (star forming regions?) ...
Astronomy and Astrophysics (ASTRO) Iowa State University – 2013-2014 1
... combines material on common naked-eye phenomena, such as daily and seasonal variations in the sky, with information on how these helped navigators determine where they are on Earth. The course "lectures" are on-line, interactive units with build in exercises, hands-on (offline) activities and layers ...
... combines material on common naked-eye phenomena, such as daily and seasonal variations in the sky, with information on how these helped navigators determine where they are on Earth. The course "lectures" are on-line, interactive units with build in exercises, hands-on (offline) activities and layers ...
- Isaac Newton Group of Telescopes
... of their evolution. More massive brown dwarfs in the Pleiades should be detectable in sufficiently deep surveys. After only 0.3% of the clusters area had been explored using IAC80 telescope at Teide Observatory, a faint object was detected, whose extremely red colour possibly indicated a very low s ...
... of their evolution. More massive brown dwarfs in the Pleiades should be detectable in sufficiently deep surveys. After only 0.3% of the clusters area had been explored using IAC80 telescope at Teide Observatory, a faint object was detected, whose extremely red colour possibly indicated a very low s ...
ALMA - ESO
... Most of the radiation emitted by stars is absorbed by dust and re-radiated in the 3 micrometer to 1 mm wavelength range The luminous IR galaxies trace regions where the concentration of galaxies is largest, and trace the formation of large scale structures. ...
... Most of the radiation emitted by stars is absorbed by dust and re-radiated in the 3 micrometer to 1 mm wavelength range The luminous IR galaxies trace regions where the concentration of galaxies is largest, and trace the formation of large scale structures. ...
Galaxy
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A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas and dust, and dark matter. The word galaxy is derived from the Greek galaxias (γαλαξίας), literally ""milky"", a reference to the Milky Way. Galaxies range in size from dwarfs with just a few thousand (103) stars to giants with one hundred trillion (1014) stars, each orbiting their galaxy's own center of mass. Galaxies are categorized according to their visual morphology, including elliptical, spiral, and irregular. Many galaxies are thought to have black holes at their active centers. The Milky Way's central black hole, known as Sagittarius A*, has a mass four million times greater than our own Sun. As of July 2015, EGSY8p7 is the oldest and most distant galaxy with a light travel distance of 13.2 billion light-years from Earth, and observed as it existed 570 million years after the Big Bang. Previously, as of May 2015, EGS-zs8-1 was the most distant known galaxy, estimated to have a light travel distance of 13.1 billion light-years away and to have 15% of the mass of the Milky Way.Approximately 170 billion (1.7 × 1011) to 200 billion (2.0 × 1011) galaxies exist in the observable universe. Most of the galaxies are 1,000 to 100,000 parsecs in diameter and usually separated by distances on the order of millions of parsecs (or megaparsecs). The space between galaxies is filled with a tenuous gas with an average density less than one atom per cubic meter. The majority of galaxies are gravitationally organized into associations known as galaxy groups, clusters, and superclusters. At the largest scale, these associations are generally arranged into sheets and filaments that are surrounded by immense voids.