University of Groningen Late-type spiral galaxies Ganda, Katia
... quiescent- are also reflected in the wide range observed in the abundance ratios. All the galaxies of Paper XI lie on or below the Mgb − σ relation for ellipticals determined by Jørgensen, Franx & Kjærgaard (1996). The authors argue that, if one considers that relation as valid for old galaxies, the ...
... quiescent- are also reflected in the wide range observed in the abundance ratios. All the galaxies of Paper XI lie on or below the Mgb − σ relation for ellipticals determined by Jørgensen, Franx & Kjærgaard (1996). The authors argue that, if one considers that relation as valid for old galaxies, the ...
Lecture Notes and Essays in Astrophysics VOLUME III
... are found. The former is the strongest contributing particle size to the total optical thickness of the cloud layers and being representative of the mean particle size. This multilayered cloud structure implies a total optical depth at the surface of ∼ 30. VIRTIS observations depend strongly on the ...
... are found. The former is the strongest contributing particle size to the total optical thickness of the cloud layers and being representative of the mean particle size. This multilayered cloud structure implies a total optical depth at the surface of ∼ 30. VIRTIS observations depend strongly on the ...
Science with the Constellation
... probe of the physics of the accretion flow as well as the space-time geometry close to the black hole. The high throughput and broad-band response of Constellation-X will allow us to utilize the iron-line diagnostic in an unprecedented manner. Observations of many individual sources will allow us to ...
... probe of the physics of the accretion flow as well as the space-time geometry close to the black hole. The high throughput and broad-band response of Constellation-X will allow us to utilize the iron-line diagnostic in an unprecedented manner. Observations of many individual sources will allow us to ...
PDF file of document - University of Iowa Astrophysics
... This packet contains a series of lab projects intended to supplement the material covered in your introductory astronomy course. As this is a separate lab course, the subjects covered may not always directly follow material discussed in the lecture. Instead, the projects are meant to support the con ...
... This packet contains a series of lab projects intended to supplement the material covered in your introductory astronomy course. As this is a separate lab course, the subjects covered may not always directly follow material discussed in the lecture. Instead, the projects are meant to support the con ...
The Collision Between The Milky Way And Andromeda
... is set to match distributions extracted from cosmological Nbody simulations (e.g., Navarro et al. 1996). Together, these models specify the total mass distribution out to the virial radius (∼ 200 − 300 kpc). In our model of the Local Group we start by adopting the models for the Milky Way and Androm ...
... is set to match distributions extracted from cosmological Nbody simulations (e.g., Navarro et al. 1996). Together, these models specify the total mass distribution out to the virial radius (∼ 200 − 300 kpc). In our model of the Local Group we start by adopting the models for the Milky Way and Androm ...
ASTR 110 Lab Manual Sections M02 M03 M04
... When we talk about how far away the stars are in our own Milky Way galaxy, we often switch to an even larger unit of distance to keep the numbers manageable. One such unit is the “light year”. A light year (ly) is the distance light travels in one year. The speed of light is enormous: 300,000 kilom ...
... When we talk about how far away the stars are in our own Milky Way galaxy, we often switch to an even larger unit of distance to keep the numbers manageable. One such unit is the “light year”. A light year (ly) is the distance light travels in one year. The speed of light is enormous: 300,000 kilom ...
Rotation Curves of Spiral Galaxies
... galaxy, and Wolf (1914) detected inclined lines in the nuclear spectrum of M81. This evidence led Pease (1918) to use the Mt. Wilson 60-inch to \investigate the rotation of the great nebula in Andromeda" by obtaining a minor axis long slit spectrum of M31 with an exposure of 84 hours taken during cl ...
... galaxy, and Wolf (1914) detected inclined lines in the nuclear spectrum of M81. This evidence led Pease (1918) to use the Mt. Wilson 60-inch to \investigate the rotation of the great nebula in Andromeda" by obtaining a minor axis long slit spectrum of M31 with an exposure of 84 hours taken during cl ...
LARGE-SCALE EXTENDED EMISSION AROUND THE HELIX
... EMISSION AROUND THE HELIX NEBULA region (PDR) that exists at the boundary between the ionization front and the molecular gas. For this reason, it is expected that there should be a ring of neutral and molecular species outside the rings of ionized gas. This is not seen in the observations. The coin ...
... EMISSION AROUND THE HELIX NEBULA region (PDR) that exists at the boundary between the ionization front and the molecular gas. For this reason, it is expected that there should be a ring of neutral and molecular species outside the rings of ionized gas. This is not seen in the observations. The coin ...
Legends Night Sky Orion
... The constellation system that we have today came from the ancient Greeks. The stories, legends and reasons why they came to be in the sky originated the very first moment that man walked this Earth. - The constellations were totally imaginary creatures, beings, and objects that farmers, poets, and a ...
... The constellation system that we have today came from the ancient Greeks. The stories, legends and reasons why they came to be in the sky originated the very first moment that man walked this Earth. - The constellations were totally imaginary creatures, beings, and objects that farmers, poets, and a ...
The 2006 RBSE Journal - National Optical Astronomy Observatory
... To pick a target I went to http://gtn.sonoma.edu/participants/catalog and looked the objects listed. I decided to use the target AO 0235+164, an AGN, for my project. I used Starry Night Pro 3.1 to locate and predict where the target would be for observation. After imputing the Right Ascension (RA) a ...
... To pick a target I went to http://gtn.sonoma.edu/participants/catalog and looked the objects listed. I decided to use the target AO 0235+164, an AGN, for my project. I used Starry Night Pro 3.1 to locate and predict where the target would be for observation. After imputing the Right Ascension (RA) a ...
T3-Cosmic Star Formation History
... basis of their optical rest-frame light and to chart the evolution of the global stellar mass density (SMD) at 0 < z < 3 (Dickinson et al. 2003). The Galaxy Evolution Explorer (GALEX) satellite has quantified the UV galaxy luminosity function (LF) of galaxies in the local Universe and its evolution a ...
... basis of their optical rest-frame light and to chart the evolution of the global stellar mass density (SMD) at 0 < z < 3 (Dickinson et al. 2003). The Galaxy Evolution Explorer (GALEX) satellite has quantified the UV galaxy luminosity function (LF) of galaxies in the local Universe and its evolution a ...
celestial navigation heaven`s guide for mere
... The stellar evolution begins with a giant molecular cloud (GMC) which is also known as the stellar nursery. Most of the empty space inside a galaxy typically contains around 0.1 to 1 particle per cm³, however the typical density of a GMC is usually a million particles per cm³. As a GMC orbits the ga ...
... The stellar evolution begins with a giant molecular cloud (GMC) which is also known as the stellar nursery. Most of the empty space inside a galaxy typically contains around 0.1 to 1 particle per cm³, however the typical density of a GMC is usually a million particles per cm³. As a GMC orbits the ga ...
FLARE SWG theme 3: high
... Pro: deeper spectroscopic follow-up observations Con: shorter wavelength (<2.5um) spectroscopy more limiting for quasar identification; however, again, most of first quasar emission lines at <2um ...
... Pro: deeper spectroscopic follow-up observations Con: shorter wavelength (<2.5um) spectroscopy more limiting for quasar identification; however, again, most of first quasar emission lines at <2um ...
Sample syllabus 2 - Johns Hopkins Center for Talented Youth
... laws governing astronomical objects and the universe itself – is the key tool for determining how the universe works, how it started, and where its headed. Students explore the structure of the universe by first learning about scale and distances of important astronomical objects such as planets, sta ...
... laws governing astronomical objects and the universe itself – is the key tool for determining how the universe works, how it started, and where its headed. Students explore the structure of the universe by first learning about scale and distances of important astronomical objects such as planets, sta ...
Educator`s Guide
... The constellation system that we have today came from the ancient Greeks. The stories, legends and reasons why they came to be in the sky originated the very first moment that man walked this Earth. - The constellations were totally imaginary creatures, beings, and objects that farmers, poets, and a ...
... The constellation system that we have today came from the ancient Greeks. The stories, legends and reasons why they came to be in the sky originated the very first moment that man walked this Earth. - The constellations were totally imaginary creatures, beings, and objects that farmers, poets, and a ...
bode elert johann
... and Johann Karl Gottlieb Schulze. Vol. i contains an 89-page star catalogue, compiled by Bode.12 This “Stern-Verzeichnis nach vier Astronomen” assembles the star catalogues of Hevelius, Flamsteed, Lacaille and Bradley.13 Concerning Flamsteed, Bode wrote: “Flamsteads [sic] vollständiges Verzeichnis, ...
... and Johann Karl Gottlieb Schulze. Vol. i contains an 89-page star catalogue, compiled by Bode.12 This “Stern-Verzeichnis nach vier Astronomen” assembles the star catalogues of Hevelius, Flamsteed, Lacaille and Bradley.13 Concerning Flamsteed, Bode wrote: “Flamsteads [sic] vollständiges Verzeichnis, ...
ROSAT Ian R. Stevens* and David K. Strickland*
... spectra with typically kT , 0:4¹1:0 keV. There are some oddities: NGC 5408 is very overluminous in X-rays, even compared with other WR galaxies; I Zw 18 has a harder Xray spectrum; NGC 1365, although thought to contain an active nucleus, has X-ray properties that are broadly similar to other WR gala ...
... spectra with typically kT , 0:4¹1:0 keV. There are some oddities: NGC 5408 is very overluminous in X-rays, even compared with other WR galaxies; I Zw 18 has a harder Xray spectrum; NGC 1365, although thought to contain an active nucleus, has X-ray properties that are broadly similar to other WR gala ...
Angular Momentum Evolution of Young Low
... 2.1. Solar-Mass and Low-Mass Stars In the last 7 yr, more than 5000 new rotational periods have been measured for cool stars in star-forming regions and young open clusters, over an age range from 1 Ma to 1 Ga. In parallel, dedicated photometric monitoring of nearby M dwarfs, aimed at planetary tra ...
... 2.1. Solar-Mass and Low-Mass Stars In the last 7 yr, more than 5000 new rotational periods have been measured for cool stars in star-forming regions and young open clusters, over an age range from 1 Ma to 1 Ga. In parallel, dedicated photometric monitoring of nearby M dwarfs, aimed at planetary tra ...
- Durham Research Online
... Analyses of the SDSS have suggested that, over about two dex of galaxy mass, the fraction of red galaxies rises with increasing environmental density (Baldry et al. 2006; Bamford et al. 2009; measured, however, through a proxy that is degenerate with group-centric distance; see Paper I; Peng et al. ...
... Analyses of the SDSS have suggested that, over about two dex of galaxy mass, the fraction of red galaxies rises with increasing environmental density (Baldry et al. 2006; Bamford et al. 2009; measured, however, through a proxy that is degenerate with group-centric distance; see Paper I; Peng et al. ...
Altair -- the ``hottest`` magnetically active star in X-rays
... in the case of rotational modulation and for the emergence/decay of weakly active regions, in contrast flaring should be accompanied by a spectral hardening. Rotational modulation can be studied with our X-ray data that covers in total three to four stellar rotations. However, the uncertainties in t ...
... in the case of rotational modulation and for the emergence/decay of weakly active regions, in contrast flaring should be accompanied by a spectral hardening. Rotational modulation can be studied with our X-ray data that covers in total three to four stellar rotations. However, the uncertainties in t ...
Stars, Galaxies, and Beyond
... covers many more topics, is vastly more detailed in what it covers, and is well worth the high price. A 3rd edition would be eagerly received and is needed to incorporate some of the exploding new astronomical knowledge. I also refer occasionally to Burke BF and Graham-Smith F, An Introduction to Ra ...
... covers many more topics, is vastly more detailed in what it covers, and is well worth the high price. A 3rd edition would be eagerly received and is needed to incorporate some of the exploding new astronomical knowledge. I also refer occasionally to Burke BF and Graham-Smith F, An Introduction to Ra ...
UvA-DARE (Digital Academic Repository)
... ever, as grains grow larger, the relative velocities keep increasing, until they reach a size where the impact velocities are so high that collisions become destructive. This is called the fragmentation barrier and provides an upper limit to the size grains can grow by coagulation, ranging from roug ...
... ever, as grains grow larger, the relative velocities keep increasing, until they reach a size where the impact velocities are so high that collisions become destructive. This is called the fragmentation barrier and provides an upper limit to the size grains can grow by coagulation, ranging from roug ...
Introduction_to_pulsar_astronomy
... In 1968, Tommy Gold writes that pulsars must be rotating neutron stars. He predicts a very slow and steady spin-down for these objects, based on the fact that they must be losing rotational energy due to their large EM emission. If the pulsations were due to vibration, then the intensity of the osci ...
... In 1968, Tommy Gold writes that pulsars must be rotating neutron stars. He predicts a very slow and steady spin-down for these objects, based on the fact that they must be losing rotational energy due to their large EM emission. If the pulsations were due to vibration, then the intensity of the osci ...
The PAH emission spectra of Large Magellanic Cloud H II regions
... and even within 30 Doradus. The LMC spectra have been compared with ISO-SWS spectra from Galactic H ii regions and with the ISOCAM observation towards a quiescent molecular cloud in the SMC (Reach et al. 2000). A correlation is found between the I7.7 /I11.2 versus I6.2 /I11.2 and the I8.6 /I11.2 ver ...
... and even within 30 Doradus. The LMC spectra have been compared with ISO-SWS spectra from Galactic H ii regions and with the ISOCAM observation towards a quiescent molecular cloud in the SMC (Reach et al. 2000). A correlation is found between the I7.7 /I11.2 versus I6.2 /I11.2 and the I8.6 /I11.2 ver ...
The Milky Way`s external disc constrained by 2MASS star counts
... Context. Thanks to recent large-scale surveys in the near infrared, such as 2MASS, the galactic plane that most suffers from extinction is revealed so its overall structure can be studied. Aims. This work aims at constraining the structure of the Milky Way external disc as seen in 2MASS data, and in ...
... Context. Thanks to recent large-scale surveys in the near infrared, such as 2MASS, the galactic plane that most suffers from extinction is revealed so its overall structure can be studied. Aims. This work aims at constraining the structure of the Milky Way external disc as seen in 2MASS data, and in ...
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.