Present
... Masses in red stars range from 8x1010 to 6x1011 Mo, if the mean stellar age is below 109 years, and significantly higher masses if the stars are older. They are probably young massive ellipticals in the final stages of star formation, where much of their stellar mass is already in place, yet very ...
... Masses in red stars range from 8x1010 to 6x1011 Mo, if the mean stellar age is below 109 years, and significantly higher masses if the stars are older. They are probably young massive ellipticals in the final stages of star formation, where much of their stellar mass is already in place, yet very ...
Document
... • Where massive stars are forming, some small number can go supernova • In certain circumstances, supernovae are associated with extraordinarily luminous, highly beamed flashes of gamma rays • These are known as Gamma Ray Bursts (GRBs) and can be used as tracers of low mass star formation • At high ...
... • Where massive stars are forming, some small number can go supernova • In certain circumstances, supernovae are associated with extraordinarily luminous, highly beamed flashes of gamma rays • These are known as Gamma Ray Bursts (GRBs) and can be used as tracers of low mass star formation • At high ...
Annual Report 2012 - Max Planck Institute for Astrophysics
... came fully independent in 1991. Kippenhahn reto rapid developments. Active areas of current tired shortly thereafter and this led to a period of research include stellar evolution, stellar atmouncertainty, which ended in 1994 with the appointspheres, accretion phenomena, nuclear and parment of Simon ...
... came fully independent in 1991. Kippenhahn reto rapid developments. Active areas of current tired shortly thereafter and this led to a period of research include stellar evolution, stellar atmouncertainty, which ended in 1994 with the appointspheres, accretion phenomena, nuclear and parment of Simon ...
Theory of Motion of Matter on the Formation of Galaxy and Star
... outwards primordial galaxy nebula center high density nuclear zone and dispersed matter, which has changed the motion direction of dispersed matter and made it move towards nebula center. Energy change occurs between primordial galaxy nebula center high density nuclear zone and dispersed matter, pro ...
... outwards primordial galaxy nebula center high density nuclear zone and dispersed matter, which has changed the motion direction of dispersed matter and made it move towards nebula center. Energy change occurs between primordial galaxy nebula center high density nuclear zone and dispersed matter, pro ...
Morphology and Environment
... E0 galaxies are nearly round, while E7 galaxies are highly flattened. Of course, the flattening we observe depends on viewing angle – the same galaxy might be classified as E0 when viewed pole-on, and E7 when viewed edge-on! In contrast, the grading of S galaxies into subtypes Sa, Sb, and Sc (and th ...
... E0 galaxies are nearly round, while E7 galaxies are highly flattened. Of course, the flattening we observe depends on viewing angle – the same galaxy might be classified as E0 when viewed pole-on, and E7 when viewed edge-on! In contrast, the grading of S galaxies into subtypes Sa, Sb, and Sc (and th ...
WSokolov-PROTVINO
... The data points plotted are described in Blain et al. (1999a) and Steidel et al. (1999). The thick and thin dashed curves describe models that represent the dust-corrected and non-dustcorrected histories derived from optical and near-IR observations, which are represented by data points. Where corre ...
... The data points plotted are described in Blain et al. (1999a) and Steidel et al. (1999). The thick and thin dashed curves describe models that represent the dust-corrected and non-dustcorrected histories derived from optical and near-IR observations, which are represented by data points. Where corre ...
17 April 2013 When Galaxies Collide Professor Carolin Crawford
... that stretch between the two galaxies to link them. The extent of the tidal tails depends on the geometry of the encounter, and they are nearly always strongly arced – although they appear completely straight if viewed edge-on to the curve. The tails develop because the gravitational force is tidal ...
... that stretch between the two galaxies to link them. The extent of the tidal tails depends on the geometry of the encounter, and they are nearly always strongly arced – although they appear completely straight if viewed edge-on to the curve. The tails develop because the gravitational force is tidal ...
The nature of extremely red galaxies in the local universe
... extremely red objects (EROs), found in optical and in infrared surveys at larger redshifts and often associated with galaxies dominated by old populations or dusty starbursts (e.g. Cimatti et al. 2004; Kong et al. 2009) although some ERGs, if at high redshift, could be classified as EROs. The outlin ...
... extremely red objects (EROs), found in optical and in infrared surveys at larger redshifts and often associated with galaxies dominated by old populations or dusty starbursts (e.g. Cimatti et al. 2004; Kong et al. 2009) although some ERGs, if at high redshift, could be classified as EROs. The outlin ...
arXiv:astro-ph/9909369 v1 22 Sep 1999
... contribution of the central region in the MIR maps and show that for this sample the FIR-Hα correlation is very good and linear (fig. 1b). This indicates that the non-linearity present in the general FIR-Hα relation is induced by the nuclear component and that in the disk of normal galaxies, the FIR ...
... contribution of the central region in the MIR maps and show that for this sample the FIR-Hα correlation is very good and linear (fig. 1b). This indicates that the non-linearity present in the general FIR-Hα relation is induced by the nuclear component and that in the disk of normal galaxies, the FIR ...
Power Point
... expected gas estimate based on optical diameter and Hubble type interactions between galaxies and interactions with the inter-cluster medium removes the gas from the galaxies ...
... expected gas estimate based on optical diameter and Hubble type interactions between galaxies and interactions with the inter-cluster medium removes the gas from the galaxies ...
The nature of the faint galaxies in the Hubble Deep Field
... by mergers (67 per cent of the mergers in Fig. 1 have B - V < 0.5) and cover a range of U - B colours ( - 1 < U - B < 1), locating them at different redshifts. These are reasonably well fitted by our galaxy models, shifted to high redshifts (z'" 1.5-3). According to these models, most of the mergers ...
... by mergers (67 per cent of the mergers in Fig. 1 have B - V < 0.5) and cover a range of U - B colours ( - 1 < U - B < 1), locating them at different redshifts. These are reasonably well fitted by our galaxy models, shifted to high redshifts (z'" 1.5-3). According to these models, most of the mergers ...
Astronomy 201 Cosmology
... What happens, if an astronaut falls into a black hole? • For the astronaut: – He/she reaches and crosses the event horizon in a finite time. – Nothing special happens while crossing the event horizon (except some highly distorted pictures of the local environment) – After crossing the event horizon ...
... What happens, if an astronaut falls into a black hole? • For the astronaut: – He/she reaches and crosses the event horizon in a finite time. – Nothing special happens while crossing the event horizon (except some highly distorted pictures of the local environment) – After crossing the event horizon ...
Slides - Indico
... -We are in the “Precision Era” of Cosmology. BBN parameters, such as Wb, Yp, (D/H)p are known with high (and increasing) precision. Uncertainties of calculations are often limited by the poor knowledge of the cross section of few reaction, at BBN energies. -Accurate measurements at low energy must b ...
... -We are in the “Precision Era” of Cosmology. BBN parameters, such as Wb, Yp, (D/H)p are known with high (and increasing) precision. Uncertainties of calculations are often limited by the poor knowledge of the cross section of few reaction, at BBN energies. -Accurate measurements at low energy must b ...
A Symbiotic Model of the Universe
... dimensions. Such flexibility in composition will make it difficult to characterize an exact nature, and in settings outside of our own universe space-time might assume different forms. Perhaps it is only the case that gravity makes apparent and/or influences the form of space-time within this univer ...
... dimensions. Such flexibility in composition will make it difficult to characterize an exact nature, and in settings outside of our own universe space-time might assume different forms. Perhaps it is only the case that gravity makes apparent and/or influences the form of space-time within this univer ...
MASSACHUSETTS INSTITUTE OF TECHNOLOGY Physics Department Physics 8.286: The Early Universe
... mass of 1014 -1015 solar masses. Answers to this question ranged all over the place, with mass estimates going from the size of a small molecular cloud up to larger than the mass of the visible universe. The scale of galaxy clusters is particularly important because they are the largest gravitationa ...
... mass of 1014 -1015 solar masses. Answers to this question ranged all over the place, with mass estimates going from the size of a small molecular cloud up to larger than the mass of the visible universe. The scale of galaxy clusters is particularly important because they are the largest gravitationa ...
astro-ph/9505110 PDF
... Our results are shown in Figures 4 and 5 (Garnett et al. 1994, 1995). We nd that the C/O ratio increases monotonically as a function of O/H, from about 1/4 solar at the lowest metallicities up to solar values. At the same time, C/N also appears to increase with O/H in the irregular galaxies, but th ...
... Our results are shown in Figures 4 and 5 (Garnett et al. 1994, 1995). We nd that the C/O ratio increases monotonically as a function of O/H, from about 1/4 solar at the lowest metallicities up to solar values. At the same time, C/N also appears to increase with O/H in the irregular galaxies, but th ...
Dark matter scaling relations and the assembly epoch of Coma early
... K2000 galaxies are brighter (and have higher stellar mass) than Coma early-types with a similar halo. Can this be an artifact related to differences in the dynamical models? Many of the K2000 models are based on B-band photometry, while we used RC -band images for the Coma galaxies. Elliptical galax ...
... K2000 galaxies are brighter (and have higher stellar mass) than Coma early-types with a similar halo. Can this be an artifact related to differences in the dynamical models? Many of the K2000 models are based on B-band photometry, while we used RC -band images for the Coma galaxies. Elliptical galax ...
THE EVOLUTION OF GALAXY NUMBER DENSITY AT Z < 8 AND
... There are a few reasons for why deep imaging programs are not easily able to convert observations to total numbers of galaxies. One of these issues is that all deep observations are incomplete. This is due to limitations in exposure times and depth such that certain galaxies will be detected more re ...
... There are a few reasons for why deep imaging programs are not easily able to convert observations to total numbers of galaxies. One of these issues is that all deep observations are incomplete. This is due to limitations in exposure times and depth such that certain galaxies will be detected more re ...
The Case for an Accelerating Universe from
... ( 2000. The Astronomical Society of the PaciÐc. All rights reserved. Printed in U.S.A. ...
... ( 2000. The Astronomical Society of the PaciÐc. All rights reserved. Printed in U.S.A. ...
Thomson, Edward Andrew (2011) Schrodinger wave
... (2) as an approximation to the full set of equations (the Free Particle Approximation developed by Coles, Spencer and Short). It has been suggested that this approach can be considered in two ways: (1) as a purely classical system that includes more physics than just gravity, or (2) as the represent ...
... (2) as an approximation to the full set of equations (the Free Particle Approximation developed by Coles, Spencer and Short). It has been suggested that this approach can be considered in two ways: (1) as a purely classical system that includes more physics than just gravity, or (2) as the represent ...
Crash Galaxies
... brisk clip of 130 kilometres per second. Computer models suggest that, should they collide, we will lose. The Milky Way will merge into Andromeda. Within four billion years the galactic pair will be one spheroidal galaxy ((Scientific American Quarterly Spring 1998, p. 109). Won’t it be fun watching ...
... brisk clip of 130 kilometres per second. Computer models suggest that, should they collide, we will lose. The Milky Way will merge into Andromeda. Within four billion years the galactic pair will be one spheroidal galaxy ((Scientific American Quarterly Spring 1998, p. 109). Won’t it be fun watching ...
Feedback in low-mass galaxies in the early Universe
... the Universe, when ionizing radiation from the first generation of stars and galaxies reionized the hydrogen gas in the intergalactic medium, which had been neutral since protons and electrons first combined 375,000 years after the Big Bang. Complex, multi-phase galactic outflows are likely to deter ...
... the Universe, when ionizing radiation from the first generation of stars and galaxies reionized the hydrogen gas in the intergalactic medium, which had been neutral since protons and electrons first combined 375,000 years after the Big Bang. Complex, multi-phase galactic outflows are likely to deter ...
Zhu Qualifier Solutions - University of Toronto Astronomy
... 1.5.2. Are there Big Bang-less cosmologies? 1.6. Question 5 1.7. Question 6 1.7.1. How can we possibly see galaxies that are moving away from us at superluminal speeds? 1.7.2. Why can’t we explain the Hubble flow through the physical motion of galaxies through space? 1.7.3. Can galaxies with recessi ...
... 1.5.2. Are there Big Bang-less cosmologies? 1.6. Question 5 1.7. Question 6 1.7.1. How can we possibly see galaxies that are moving away from us at superluminal speeds? 1.7.2. Why can’t we explain the Hubble flow through the physical motion of galaxies through space? 1.7.3. Can galaxies with recessi ...
Observational motivation for Dark Matter
... Before matter dominates, growth is suppressed Afterwards, growth depends on sound velocity and amount of non interacting matter On small scales, pressure will bounce back the perturbations, depending on the sound crossing time and time since passing the Jeans scale ...
... Before matter dominates, growth is suppressed Afterwards, growth depends on sound velocity and amount of non interacting matter On small scales, pressure will bounce back the perturbations, depending on the sound crossing time and time since passing the Jeans scale ...
Big Bang
The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution. The model accounts for the fact that the universe expanded from a very high density and high temperature state, and offers a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background, large scale structure, and Hubble's Law. If the known laws of physics are extrapolated beyond where they are valid, there is a singularity. Modern measurements place this moment at approximately 13.8 billion years ago, which is thus considered the age of the universe. After the initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, and later simple atoms. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies.Since Georges Lemaître first noted, in 1927, that an expanding universe might be traced back in time to an originating single point, scientists have built on his idea of cosmic expansion. While the scientific community was once divided between supporters of two different expanding universe theories, the Big Bang and the Steady State theory, accumulated empirical evidence provides strong support for the former. In 1929, from analysis of galactic redshifts, Edwin Hubble concluded that galaxies are drifting apart, important observational evidence consistent with the hypothesis of an expanding universe. In 1965, the cosmic microwave background radiation was discovered, which was crucial evidence in favor of the Big Bang model, since that theory predicted the existence of background radiation throughout the universe before it was discovered. More recently, measurements of the redshifts of supernovae indicate that the expansion of the universe is accelerating, an observation attributed to dark energy's existence. The known physical laws of nature can be used to calculate the characteristics of the universe in detail back in time to an initial state of extreme density and temperature.