Astronomy 201 Cosmology
... • White holes - a phenomenon analogous to a black hole from which light can only escape. No obvious way to make or power one • Wormholes - conduits between two points in spacetime. Unstable, difficult to avoid singularity without going faster than c, solutions with timelike paths only size of elemen ...
... • White holes - a phenomenon analogous to a black hole from which light can only escape. No obvious way to make or power one • Wormholes - conduits between two points in spacetime. Unstable, difficult to avoid singularity without going faster than c, solutions with timelike paths only size of elemen ...
Observational evidence for AGN feedback in early
... models, early-type galaxies have helped provide the insights into what physics was still missing from them and they continue to do so. The vast majority of early-type galaxies appear to have formed most of their stars at high redshift on very short time-scales as suggested by the stellar population ...
... models, early-type galaxies have helped provide the insights into what physics was still missing from them and they continue to do so. The vast majority of early-type galaxies appear to have formed most of their stars at high redshift on very short time-scales as suggested by the stellar population ...
Preliminary Talk Abstract Book - MoCA
... from dark matter halos to the Inter-Galactic Medium. I will first review the microphysics of this process, highlighting the various forms of feedback that emerge from star formation: radiation pressure, ionising light, stellar winds, SN explosions not to mention the production of metals and dust. Th ...
... from dark matter halos to the Inter-Galactic Medium. I will first review the microphysics of this process, highlighting the various forms of feedback that emerge from star formation: radiation pressure, ionising light, stellar winds, SN explosions not to mention the production of metals and dust. Th ...
X. Nuclear star clusters in low-mass early-type galaxies
... that the evolution of NSCs and SMBHs may possibly somehow be linked. Likely there is some interaction between NSCs and SMBHs, such that one may prevent the growth of the other or even destroy it (McLaughlin, King & Nayakshin 2006; Merritt 2009; Nayakshin, Wilkinson & King 2009). The Milky Way was th ...
... that the evolution of NSCs and SMBHs may possibly somehow be linked. Likely there is some interaction between NSCs and SMBHs, such that one may prevent the growth of the other or even destroy it (McLaughlin, King & Nayakshin 2006; Merritt 2009; Nayakshin, Wilkinson & King 2009). The Milky Way was th ...
Digital Universe Guide - American Museum of Natural History
... Turn the stars off by pressing the g1=stars group button in the upper left and turn on the open clusters (the oc button) and the globular clusters (the gc button). Also turn on the constellation connectivity lines (constel button) so that you know where you are in the sky. ...
... Turn the stars off by pressing the g1=stars group button in the upper left and turn on the open clusters (the oc button) and the globular clusters (the gc button). Also turn on the constellation connectivity lines (constel button) so that you know where you are in the sky. ...
Markov Chain Monte Carlo Modeling of High-Redshift Quasar
... z ' 2 and z ' 6 using new data obtained with the Hubble Space Telescope. I describe a new method for removing the point source flux using Markov Chain Monte Carlo parameter estimation and simultaneous modeling of the point source and host galaxy. I then discuss applications of this method to underst ...
... z ' 2 and z ' 6 using new data obtained with the Hubble Space Telescope. I describe a new method for removing the point source flux using Markov Chain Monte Carlo parameter estimation and simultaneous modeling of the point source and host galaxy. I then discuss applications of this method to underst ...
Chapter 5 The Evolutionary Paths Of Nearby Galaxies
... also note that a few early-type galaxies lie well outside the red sequence. These are misclassified or peculiar objects and their properties will be investigated later. To investigate whether the quenching is due to AGN feedback or environmental effects, I divide the sample according to nuclear acti ...
... also note that a few early-type galaxies lie well outside the red sequence. These are misclassified or peculiar objects and their properties will be investigated later. To investigate whether the quenching is due to AGN feedback or environmental effects, I divide the sample according to nuclear acti ...
Stellar Populations of Dwarf Elliptical Galaxies: UBVRI Photometry
... UBVRI images of 16 dwarf elliptical galaxies in the Virgo Cluster were obtained with the VATT 1.8m on 2003 March 29-31. The telescope was equipped with CCD26, a thinned Loral 3 2048 × 2048 CCD with 15µm pixels. CCD26 has a read noise of 5.7 e− and a gain of 1.9 e− per ADU was used. On-chip binning o ...
... UBVRI images of 16 dwarf elliptical galaxies in the Virgo Cluster were obtained with the VATT 1.8m on 2003 March 29-31. The telescope was equipped with CCD26, a thinned Loral 3 2048 × 2048 CCD with 15µm pixels. CCD26 has a read noise of 5.7 e− and a gain of 1.9 e− per ADU was used. On-chip binning o ...
Seeding the Universe with Life
... Nature creates objects and patterns but does not call them names. Only humans use definitions. Therefore, “what is Life” cannot be answered by Nature. It must be answered by human beings using human faculties: our instincts, emotions and rational arguments. Whomever we accept as living beings – they ...
... Nature creates objects and patterns but does not call them names. Only humans use definitions. Therefore, “what is Life” cannot be answered by Nature. It must be answered by human beings using human faculties: our instincts, emotions and rational arguments. Whomever we accept as living beings – they ...
Mapping the Pathways of Galaxy Transformation Across Time and
... Bulges play a pivotal role in how a galaxy might evolve. However, the exact mechanisms involved in shaping their hosts and even their demographic evolution with cosmic time still remain an unanswered piece in the galaxy formation puzzle. In this talk I will present an innovative study into the stell ...
... Bulges play a pivotal role in how a galaxy might evolve. However, the exact mechanisms involved in shaping their hosts and even their demographic evolution with cosmic time still remain an unanswered piece in the galaxy formation puzzle. In this talk I will present an innovative study into the stell ...
THE STAR FORMATION AND NUCLEAR ACCRETION HISTORIES OF NORMAL GALAXIES
... may be most abundant at z < ∼ 1 and, if so, they could produce a substantial fraction of the “normal” galaxy X-ray flux at these redshifts. Given their similar evolution, spectral shapes (e.g., Ptak et al. 1999), and potentially similar luminosities, it may be difficult to disentangle the X-ray emis ...
... may be most abundant at z < ∼ 1 and, if so, they could produce a substantial fraction of the “normal” galaxy X-ray flux at these redshifts. Given their similar evolution, spectral shapes (e.g., Ptak et al. 1999), and potentially similar luminosities, it may be difficult to disentangle the X-ray emis ...
Jul y 9- 11,
... central supermassive black holes (SMBHs) will be more often present even in smaller galaxies when seeds are generated from the remnants of the first massive stars rather than via direct gas collapse. Consequently, measurement of the local occupation fraction provides an observational discriminator b ...
... central supermassive black holes (SMBHs) will be more often present even in smaller galaxies when seeds are generated from the remnants of the first massive stars rather than via direct gas collapse. Consequently, measurement of the local occupation fraction provides an observational discriminator b ...
Sample syllabus 2 - Johns Hopkins Center for Talented Youth
... Course Description: When the sun runs out of fuel, will it explode in a giant supernova or fade out into a white dwarf? Does every galaxy revolve around a super-massive black hole? Will the universe continue to expand, or will it eventually collapse back upon itself in a reversal of the Big Bang? As ...
... Course Description: When the sun runs out of fuel, will it explode in a giant supernova or fade out into a white dwarf? Does every galaxy revolve around a super-massive black hole? Will the universe continue to expand, or will it eventually collapse back upon itself in a reversal of the Big Bang? As ...
T3-Cosmic Star Formation History
... By modeling the emission history of all stars in the Universe at UV, optical, and IR wavelengths from the present epoch to z ≈ 8 and beyond, one can then shed light on some key questions in galaxy formation and evolution studies: Is there a characteristic cosmic epoch of the formation of stars and h ...
... By modeling the emission history of all stars in the Universe at UV, optical, and IR wavelengths from the present epoch to z ≈ 8 and beyond, one can then shed light on some key questions in galaxy formation and evolution studies: Is there a characteristic cosmic epoch of the formation of stars and h ...
Astrophysics for Physicists.
... then taking up galaxies to end with extragalactic astronomy and cosmology. One issue about which I had to give some thought is the placement of the basic physics topics which I develop in the book. A possible approach would have been to develop all the necessary basic physics topics at the beginning ...
... then taking up galaxies to end with extragalactic astronomy and cosmology. One issue about which I had to give some thought is the placement of the basic physics topics which I develop in the book. A possible approach would have been to develop all the necessary basic physics topics at the beginning ...
A New Science Strategy for Space Astronomy and Astrophysics
... groundand space-based research. It recommended a single large initiative for space, the Space Infrared Telescope Facility, which now appears to be getting under way, albeit on a smaller scale than was originally envisaged. The Bahcall committee members recognized that preparations for any subsequent ...
... groundand space-based research. It recommended a single large initiative for space, the Space Infrared Telescope Facility, which now appears to be getting under way, albeit on a smaller scale than was originally envisaged. The Bahcall committee members recognized that preparations for any subsequent ...
Spring 2015 Mercury - Astronomical Society of the Pacific
... observed it in 1764 and noted a nebula surrounding the cluster. Using a much more powerful telescope, Caroline and William Herschel viewed the Eagle Nebula in 1783 and counted more than 100 stars. David Malin, the brilliant astrophotographer at the AngloAustralian Observatory, was responsible for wh ...
... observed it in 1764 and noted a nebula surrounding the cluster. Using a much more powerful telescope, Caroline and William Herschel viewed the Eagle Nebula in 1783 and counted more than 100 stars. David Malin, the brilliant astrophotographer at the AngloAustralian Observatory, was responsible for wh ...
2. The X-ray-Radio correlation for bulgeless galaxies
... Table1: Sensitivity limits for the C-COSMOS Survey. The flux sensitivity of the surveys is the same regardless of the distance of the objects, so the luminosity limit is defined solely by the redshifts................................................................................................... ...
... Table1: Sensitivity limits for the C-COSMOS Survey. The flux sensitivity of the surveys is the same regardless of the distance of the objects, so the luminosity limit is defined solely by the redshifts................................................................................................... ...
The science case for - Astrophysics
... photons which re-ionised the Universe some 200million years after the Big Bang, and made it transparent? These objects may be visible through their supernovae, or their ionisation zones. How many types of matter exist? What is dark matter? Where is it? Most matter is transparent, and is detectable o ...
... photons which re-ionised the Universe some 200million years after the Big Bang, and made it transparent? These objects may be visible through their supernovae, or their ionisation zones. How many types of matter exist? What is dark matter? Where is it? Most matter is transparent, and is detectable o ...
The Norma cluster (ACO3627) – II. The near-infrared Ks
... structure (Binggeli et al. 1988). Clusters containing cD galaxies seem to have a steeper bright end than those without cD galaxies. Often the brightest galaxy is excluded to obtain a better fit, particularly in cD clusters. The Schechter parameters have also been found to vary depending on the regio ...
... structure (Binggeli et al. 1988). Clusters containing cD galaxies seem to have a steeper bright end than those without cD galaxies. Often the brightest galaxy is excluded to obtain a better fit, particularly in cD clusters. The Schechter parameters have also been found to vary depending on the regio ...
Hubble Deep Field Academy -- Overview
... description, the concepts covered, prerequisites, and the target audience. Science Background: Provides information about the science behind the activity. It clarifies important concepts used in the activity and contains a message from the scientist who worked with the team to develop it. Lesson Pla ...
... description, the concepts covered, prerequisites, and the target audience. Science Background: Provides information about the science behind the activity. It clarifies important concepts used in the activity and contains a message from the scientist who worked with the team to develop it. Lesson Pla ...
Chapter 10 Formation and evolution of the Local Group
... used (Θ0 = 220 km s−1 ), although it is even somewhat larger than a suggested revised velocity (239 km s−1 ) as discussed below in Section 10.2.3. As discussed more fully in Section 10.2.2 Tolstoy, Hill and Tosi (2009) state how all dwarf galaxies in the LG possess old (>10 Gyr) stars. van den Bergh ...
... used (Θ0 = 220 km s−1 ), although it is even somewhat larger than a suggested revised velocity (239 km s−1 ) as discussed below in Section 10.2.3. As discussed more fully in Section 10.2.2 Tolstoy, Hill and Tosi (2009) state how all dwarf galaxies in the LG possess old (>10 Gyr) stars. van den Bergh ...
Elliptical Galaxies
... Dark haloes: mass at large radius Spiral galaxy rotation curves have been used to show that they are embedded in dark haloes that contain three to ten times as much mass as is visible in stars, gas and dust. Can dark haloes be detected in elliptical galaxies? The velocity dispersion in many galaxies ...
... Dark haloes: mass at large radius Spiral galaxy rotation curves have been used to show that they are embedded in dark haloes that contain three to ten times as much mass as is visible in stars, gas and dust. Can dark haloes be detected in elliptical galaxies? The velocity dispersion in many galaxies ...
Rest-frame Optical Spectra: A Window into Galaxy Formation at z~2
... population models à SF-history. • Robust estimates of dynamical mass (combined with HST imaging). • Estimate of stellar metallicity. • Stacking to detect absorption lines in fainter galaxies. ...
... population models à SF-history. • Robust estimates of dynamical mass (combined with HST imaging). • Estimate of stellar metallicity. • Stacking to detect absorption lines in fainter galaxies. ...
The environment of high-redshift AGN OLIMPIA JUDIT FOGASY
... radio galaxies suggest that these AGN live in overdense environment surrounded by star-forming Lyα-emitters and submillimeter galaxies. At smaller scales several high-z quasars and radio galaxies have gas-rich, star-forming companion galaxies, such as the subject of the appended paper, the system of ...
... radio galaxies suggest that these AGN live in overdense environment surrounded by star-forming Lyα-emitters and submillimeter galaxies. At smaller scales several high-z quasars and radio galaxies have gas-rich, star-forming companion galaxies, such as the subject of the appended paper, the system of ...
Observable universe
The observable universe consists of the galaxies and other matter that can, in principle, be observed from Earth at the present time because light and other signals from these objects has had time to reach the Earth since the beginning of the cosmological expansion. Assuming the universe is isotropic, the distance to the edge of the observable universe is roughly the same in every direction. That is, the observable universe is a spherical volume (a ball) centered on the observer. Every location in the Universe has its own observable universe, which may or may not overlap with the one centered on Earth.The word observable used in this sense does not depend on whether modern technology actually permits detection of radiation from an object in this region (or indeed on whether there is any radiation to detect). It simply indicates that it is possible in principle for light or other signals from the object to reach an observer on Earth. In practice, we can see light only from as far back as the time of photon decoupling in the recombination epoch. That is when particles were first able to emit photons that were not quickly re-absorbed by other particles. Before then, the Universe was filled with a plasma that was opaque to photons.The surface of last scattering is the collection of points in space at the exact distance that photons from the time of photon decoupling just reach us today. These are the photons we detect today as cosmic microwave background radiation (CMBR). However, with future technology, it may be possible to observe the still older relic neutrino background, or even more distant events via gravitational waves (which also should move at the speed of light). Sometimes astrophysicists distinguish between the visible universe, which includes only signals emitted since recombination—and the observable universe, which includes signals since the beginning of the cosmological expansion (the Big Bang in traditional cosmology, the end of the inflationary epoch in modern cosmology). According to calculations, the comoving distance (current proper distance) to particles from the CMBR, which represent the radius of the visible universe, is about 14.0 billion parsecs (about 45.7 billion light years), while the comoving distance to the edge of the observable universe is about 14.3 billion parsecs (about 46.6 billion light years), about 2% larger.The best estimate of the age of the universe as of 2015 is 7010137990000000000♠13.799±0.021 billion years but due to the expansion of space humans are observing objects that were originally much closer but are now considerably farther away (as defined in terms of cosmological proper distance, which is equal to the comoving distance at the present time) than a static 13.8 billion light-years distance. It is estimated that the diameter of the observable universe is about 28 gigaparsecs (91 billion light-years, 8.8×1026 metres or 5.5×1023 miles), putting the edge of the observable universe at about 46–47 billion light-years away.