1 HABITABLE ZONES IN THE UNIVERSE GUILLERMO GONZALEZ
... Hart (1978, 1979) presented a detailed and mathematical study of the CHZ. He modeled the evolution of the Earth’s climate since its formation, including volcanic outgassing, atmospheric loss, the greenhouse effect, albedo variations, biomass variation, various geophysical processes, and the gradual ...
... Hart (1978, 1979) presented a detailed and mathematical study of the CHZ. He modeled the evolution of the Earth’s climate since its formation, including volcanic outgassing, atmospheric loss, the greenhouse effect, albedo variations, biomass variation, various geophysical processes, and the gradual ...
The significant contribution of minor mergers to the cosmic star
... emission-line results in B04 are consistent with the recent literature (e.g. Tresse & Maddox 1998; Pérez-González et al. 2008) and their D4000-measured SFRs for ETGs (which have a median value of ∼0.08 M⊙ yr−1 ) are in agreement with those calculated via UV/optical/IR photometry (e.g. Kaviraj et a ...
... emission-line results in B04 are consistent with the recent literature (e.g. Tresse & Maddox 1998; Pérez-González et al. 2008) and their D4000-measured SFRs for ETGs (which have a median value of ∼0.08 M⊙ yr−1 ) are in agreement with those calculated via UV/optical/IR photometry (e.g. Kaviraj et a ...
The Spitzer/GLIMPSE Surveys - UW-Madison Astronomy
... however, cannot explain the nonplanar structures or wiggly filaments that are prevalent among IRDC morphologies. Differential Galactic rotation also tends to stretch large molecular clouds into linear structures, but this mechanism would only distort in the plane of the Galaxy leaving the wiggly fil ...
... however, cannot explain the nonplanar structures or wiggly filaments that are prevalent among IRDC morphologies. Differential Galactic rotation also tends to stretch large molecular clouds into linear structures, but this mechanism would only distort in the plane of the Galaxy leaving the wiggly fil ...
Extragalactic Distances from Planetary Nebulae
... Elliptical galaxies do not have many (any?) 2 M main sequence stars. But they do have large numbers of 1 M stars. If some are in close binary systems which coalesce on the main sequence, the product may evolve into an [O III]-bright planetary. The ratio of bright planetaries to blue stragglers is ...
... Elliptical galaxies do not have many (any?) 2 M main sequence stars. But they do have large numbers of 1 M stars. If some are in close binary systems which coalesce on the main sequence, the product may evolve into an [O III]-bright planetary. The ratio of bright planetaries to blue stragglers is ...
Andromeda Nebula Lies Outside Milky Way Galaxy
... knew how far away the nebulae were, he could compare their distance to their red-shift to learn the relationship. He concluded that the most distant objects are speeding away from us at perhaps thousands of miles per second. Dr. Hubble's recent discoveries show that the volume of space itself is exp ...
... knew how far away the nebulae were, he could compare their distance to their red-shift to learn the relationship. He concluded that the most distant objects are speeding away from us at perhaps thousands of miles per second. Dr. Hubble's recent discoveries show that the volume of space itself is exp ...
Power Point
... • at moderate redshifts the whole of the galaxy cluster core and its outskirts are within the field of view of a radio telescope (nearby this not the case – one has to target individual galaxies in clusters one by one) • around a cluster there are many more galaxies that lie within a single telescop ...
... • at moderate redshifts the whole of the galaxy cluster core and its outskirts are within the field of view of a radio telescope (nearby this not the case – one has to target individual galaxies in clusters one by one) • around a cluster there are many more galaxies that lie within a single telescop ...
Wednesday, Sept. 24 - Department of Physics and Astronomy
... gas. • Comparison of strengths of absorption lines of different elements in the gas gives – Density – Temperature • Can get these characteristics for outer layers of star from its absorption line spectrum. ...
... gas. • Comparison of strengths of absorption lines of different elements in the gas gives – Density – Temperature • Can get these characteristics for outer layers of star from its absorption line spectrum. ...
The Galactic evolution of phosphorus
... therein). This is not the case for phosphorus, that, before this work, had never been analysed systematically in cool stars. The reason why was already given by Struve (1930): no P i line is available in the “ordinary” range of the observed spectra of stars of spectral type F, G, or K. Some P ii and ...
... therein). This is not the case for phosphorus, that, before this work, had never been analysed systematically in cool stars. The reason why was already given by Struve (1930): no P i line is available in the “ordinary” range of the observed spectra of stars of spectral type F, G, or K. Some P ii and ...
Dark-matter halo mergers as a fertile environment for low
... until z = 12, where we clearly see two mini-haloes, as depicted by the circles. The latter merge to form a mini-halo of 7 × 105 M . Note here that the size of the circles corresponds to the physical mass of the haloes and is provided by the halo finder employed in YT; bigger circles represent more ...
... until z = 12, where we clearly see two mini-haloes, as depicted by the circles. The latter merge to form a mini-halo of 7 × 105 M . Note here that the size of the circles corresponds to the physical mass of the haloes and is provided by the halo finder employed in YT; bigger circles represent more ...
sections 12-15 instructor notes
... We require that basic distribution function to describe not only the stellar distribution in our immediate Galactic surroundings, but also to serve as a basis from which we explore how it varies from one point in our Galaxy to another. We can trace it back into time, and, on the basis of some simple ...
... We require that basic distribution function to describe not only the stellar distribution in our immediate Galactic surroundings, but also to serve as a basis from which we explore how it varies from one point in our Galaxy to another. We can trace it back into time, and, on the basis of some simple ...
Astrophysics Questions (DRAFT)
... 94. Sketch a typical cooling function (T ) for diuse interstellar gas and identify its prominent features. Overplot a hypothetical heating curve and show how to identify points of thermal equilibrium and their stability. 95. Explain the physics of 21 cm radio emission from neutral hydrogen atoms. ...
... 94. Sketch a typical cooling function (T ) for diuse interstellar gas and identify its prominent features. Overplot a hypothetical heating curve and show how to identify points of thermal equilibrium and their stability. 95. Explain the physics of 21 cm radio emission from neutral hydrogen atoms. ...
BRC_prop1 - CoolWiki
... of 1.2 kpc and age 1.5 Myr of the stars in BRC27. This distance measurement was consistent with the findings of Shevchenko (1999) who placed the distance at 1.05 ± 0.15 kpc. Recently Gregorio-Hetem et al (2009) did a wide-field X-ray study of the CMa OB1/R1 star forming regions in an attempt to find ...
... of 1.2 kpc and age 1.5 Myr of the stars in BRC27. This distance measurement was consistent with the findings of Shevchenko (1999) who placed the distance at 1.05 ± 0.15 kpc. Recently Gregorio-Hetem et al (2009) did a wide-field X-ray study of the CMa OB1/R1 star forming regions in an attempt to find ...
The Southern Fall PDF - Treasures of the Southern Sky
... few obvious star-forming regions, and it emphasizes the very bright nucleus. NGC 3521 is superficially similar to Messier 63 and belongs to the class of compact bright galaxies recognized as lacking a welldefined spiral arm structure. Such galaxies have an appearance that is as remote from the “gran ...
... few obvious star-forming regions, and it emphasizes the very bright nucleus. NGC 3521 is superficially similar to Messier 63 and belongs to the class of compact bright galaxies recognized as lacking a welldefined spiral arm structure. Such galaxies have an appearance that is as remote from the “gran ...
1 Dark matter and dark energy comprise over 90% of the Universe
... the Milky Way, such as brown dwarfs or black holes can produce microlensing of a distant star, causing it to brighten. These microlensing objects are referred to as massive compact halo objects or MACHOs for short. If a MACHO came into alignment with the observer and the distant star, the brightness ...
... the Milky Way, such as brown dwarfs or black holes can produce microlensing of a distant star, causing it to brighten. These microlensing objects are referred to as massive compact halo objects or MACHOs for short. If a MACHO came into alignment with the observer and the distant star, the brightness ...
Image Analysis of Planetary Nebula NGC 6543 South Carolina State University
... interior of the clouds very cool through molecular radiation. These clouds can be as large as 60 pc in diameter with a mass up to a million solar masses. Within these molecular clouds, stars are born and the energy from these hot stars and supernova explosions create coronal gases. X-ray telescopes ...
... interior of the clouds very cool through molecular radiation. These clouds can be as large as 60 pc in diameter with a mass up to a million solar masses. Within these molecular clouds, stars are born and the energy from these hot stars and supernova explosions create coronal gases. X-ray telescopes ...
Stellar dust production and composition in the Magellanic Clouds F. Kemper
... spectral range, but with a more extensive spectral range it was later shown that the ‘emission feature’ was really a lack of molecular absorption (Speck et al., 2006). Further ISO studies focused on the 10 µm emission features in M-stars (Dijkstra et al., 2005), showing the presence of alumina and a ...
... spectral range, but with a more extensive spectral range it was later shown that the ‘emission feature’ was really a lack of molecular absorption (Speck et al., 2006). Further ISO studies focused on the 10 µm emission features in M-stars (Dijkstra et al., 2005), showing the presence of alumina and a ...
KINEMATIC MEASUREMENTS OF GAS AND STARS IN SPIRAL
... gas, in either atomic (H I) or molecular (H 2 ) form. The first rotation curve for an external galaxy using H I was obtained by [5], again for M31, and even in this pioneering measurement they showed that the curve in H I could be measured out to at least twice as far from the galactic centre as the ...
... gas, in either atomic (H I) or molecular (H 2 ) form. The first rotation curve for an external galaxy using H I was obtained by [5], again for M31, and even in this pioneering measurement they showed that the curve in H I could be measured out to at least twice as far from the galactic centre as the ...
Galaxy Hunters Article, Cosmology Information, First Star Facts
... had a profound effect on future galaxy formation. They heated surrounding gases and bombarded them with ultraviolet light. And when they exploded, the stars seeded the universe, and the next generation of stars, with the first supply of heavy elements, including the oxygen we breathe. The explosive ...
... had a profound effect on future galaxy formation. They heated surrounding gases and bombarded them with ultraviolet light. And when they exploded, the stars seeded the universe, and the next generation of stars, with the first supply of heavy elements, including the oxygen we breathe. The explosive ...
A Universe of Disks
... experiments to search for turbulence in flows that resemble accretion disks, but again the results have been debated. Although turbulence is sometimes seen in these experiments, it may arise from effects that would not be present in a real accretion disk. Nevertheless, astrophysicists have persisted ...
... experiments to search for turbulence in flows that resemble accretion disks, but again the results have been debated. Although turbulence is sometimes seen in these experiments, it may arise from effects that would not be present in a real accretion disk. Nevertheless, astrophysicists have persisted ...
Accretion Disk
... When the mass ratios are large, or when the donor star has a deep convective layer (so R ∝ M-1/3), mass loss will occur on a dynamical timescale. The result will be common envelope evolution, in which • The energy released from the orbit will be greater than the binding energy of the envelope. The ...
... When the mass ratios are large, or when the donor star has a deep convective layer (so R ∝ M-1/3), mass loss will occur on a dynamical timescale. The result will be common envelope evolution, in which • The energy released from the orbit will be greater than the binding energy of the envelope. The ...
The mass of the Milky Way: Limits from a newly assembled set of
... rise to a declining rotation curve is insufficient to bind many of our sample objects to the Galaxy; a possible lower limit on the mass of the Galaxy is about 2.2 × 1012 M . To be more quantitative, we adopt a Bayesian likelihood approach to reproduce the observed distribution of the current positi ...
... rise to a declining rotation curve is insufficient to bind many of our sample objects to the Galaxy; a possible lower limit on the mass of the Galaxy is about 2.2 × 1012 M . To be more quantitative, we adopt a Bayesian likelihood approach to reproduce the observed distribution of the current positi ...
Starburst Galaxies Under the Microscope: High
... Also commonly detected are the rovibrational lines of H2. Arising from levels about 6 000 K above the ground state, these lines trace hot molecular gas. While the diagnostic use of these lines is complicated by the fact that multiple excitation mechanisms can play a role (and probably do play a role ...
... Also commonly detected are the rovibrational lines of H2. Arising from levels about 6 000 K above the ground state, these lines trace hot molecular gas. While the diagnostic use of these lines is complicated by the fact that multiple excitation mechanisms can play a role (and probably do play a role ...
Ionization structure of an HII region
... the product of a frequency dependant absorption cross section σabs and the local number density of the dust particles. For simplicity we shall assume that the dust to gas ratio (nD /n) is constant everwhere in the HII region. In the program, one only needs to setting up the frequency dependent κD (ν ...
... the product of a frequency dependant absorption cross section σabs and the local number density of the dust particles. For simplicity we shall assume that the dust to gas ratio (nD /n) is constant everwhere in the HII region. In the program, one only needs to setting up the frequency dependent κD (ν ...
The MORGANA model for the rise of galaxies and active nuclei
... (iv) accretion on to BHs and its feedback on to the galaxy (through radio jets and quasar-triggered galaxy winds) are built in. The increased level of sophistication allows to move from a phenomenological description of gas physics, based on simple scalings with the depth of the DM halo potential, t ...
... (iv) accretion on to BHs and its feedback on to the galaxy (through radio jets and quasar-triggered galaxy winds) are built in. The increased level of sophistication allows to move from a phenomenological description of gas physics, based on simple scalings with the depth of the DM halo potential, t ...