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Neutron Stars
Neutron Stars

... employing the relativistic equations of stellar structure following from Einstein’s equations of general relativity. This work demonstrated, among other interesting ideas, that neutron stars could not be of arbitrarily large mass: general relativity introduces the concept of a neutron star maximum m ...
EXPLORING FUNDAMENTAL PHYSICS WITH NEUTRON STARS
EXPLORING FUNDAMENTAL PHYSICS WITH NEUTRON STARS

... who are trained in the physics of microscopic systems of degenerate nucleons or high-energy particles, but are probably not familiar with astrophysical issues in general, and with the macroscopic behaviour of objects strongly bound by gravity in particular. Here, instead, we introduce the subject of ...
Evolution of the Highest Redshift Quasars
Evolution of the Highest Redshift Quasars

... – Only BHs with ideal growth conditions (negative feedback not important) can grow to billion Msun at z~6 – Low BH fraction in halos at the high luminosity (mass) end • Steep quasar luminosity function? ...
The Interstellar Medium White Paper
The Interstellar Medium White Paper

... was primarily responsible for the inflation of the Fermi Bubbles and the corresponding radio lobes. We also cannot yet be sure whether the Bubbles are quasi steady state phenomena or the signatures of much more recent and transient events. Such questions feed into one of the most important problems ...
The Celestial Origin of Atoms
The Celestial Origin of Atoms

... as applied to our own Sun, and by extrapolation, to all stars. (The discrepancy is roughly a factor of two, and this can very likely be put down to problems in our understanding of neutrinos, rather than some defect in stellar physics.) More precisely, it corroborates our ideas about hydrogen fusion ...
Lecture 9: The interstellar medium (ISM)
Lecture 9: The interstellar medium (ISM)

... higher pressures, but this is the result of their high masses, causing them to collapse and be compressed under their self gravity (they are the only phase of the ISM where self-gravity dominates over gas pressure) ...
Detection of the Stochastic Background of nHz Gravitational Radiation from Massive Black
Detection of the Stochastic Background of nHz Gravitational Radiation from Massive Black

... of space. Accelerating masses radiate “distortions”, or “ripples”, in the fabric of space with dimensionless amplitude, h(x,t). This is gravitational radiation, which propagates away at speed of light. A Binary MBH ten billion light years away with orbit of 5y will produce a distortion of space by j ...
8-4.9 - S2TEM Centers SC
8-4.9 - S2TEM Centers SC

... 2. Ask them to share what they know about it. 3. Make sure they are aware that a galaxy is a very large collection of stars, dust, and gas held together by the force of gravity. They should also be aware that not all galaxies look the same. 4. Provide students with copies of the activity sheet and t ...
Summary of Talks at Growing Black Holes 2004 in Garching
Summary of Talks at Growing Black Holes 2004 in Garching

... -> High resolution CO observations of the object resolve it spatially into two peaks. It also resolved in velocity space, with a CO line width of 280 km/s and a bulge mass estimate of 1e10 solar masses within 2kpc, which is lower than expected from M sigma relation. Is this object not fully assemble ...
THE PRIMORDIAL HELIUM ABUNDANCE Manuel Peimbert
THE PRIMORDIAL HELIUM ABUNDANCE Manuel Peimbert

... cosmology, (b) testing the standard big bang nucleosynthesis, (c) studying the physical conditions in H II regions, (d) providing the initial conditions for stellar evolution models, and (e) testing the galactic chemical evolution models. ...
Joint formation of QSOs and spheroids: QSOs as clocks of star
Joint formation of QSOs and spheroids: QSOs as clocks of star

... suggesting that star formation begins in the hosting spheroids at a time t* and proceeds vigoursly at least until the time tQSO, when the QSO shines. Here we estimate the duration of the star formation phase and its possible dependence on the mass. The statistics on broad emission lines suggest that ...
Gas fraction and star formation efficiency at z \< 1.0⋆⋆⋆⋆⋆⋆
Gas fraction and star formation efficiency at z \< 1.0⋆⋆⋆⋆⋆⋆

... higher-J lines are also plotted. Table 2 reports all line parameters, and also the upper limits for the non detections. Integrated signals and velocity widths have been computed from Gaussian fits. These also give the central velocities, with respect to the optical redshift of Table 1. There are som ...
Measuring distances to the edge of the local group
Measuring distances to the edge of the local group

... 3109 using Cepheid variable stars. These stars have a well-known period-luminosity relationship caused by the radial pulsation of the star, which was first characterized by Leavitt in 1912. They can thus be used as standard candles once the period of a particular star is known. To accomplish this, w ...
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... is composed of perhaps a few hundred billion stars plus many different types of gas, dust, planets, and so on. In the directions in which we see the Milky Way in the sky, we are looking through the relatively thin, pancake-like disk of matter that forms a major part of our Milky Way Galaxy. ...
ROTATION CURVES OF HIGH-LUMINOSITY SPIRAL GALAXIES
ROTATION CURVES OF HIGH-LUMINOSITY SPIRAL GALAXIES

... values as discrepant as A = +26, B = -37 (Asteriadis, 1977). At the la level, A = -B is not excluded, i.e., the rotation curve could be flat in the solar vicinity. More likely, there is a negative velocity gra­ dient at the position of the sun. Because spiral arms show positive velocity gradients, t ...
Gas fraction and star formation efficiency at z< 1.0
Gas fraction and star formation efficiency at z< 1.0

... global SFR decreases with cosmic time as SFR ∝ (1+z)2.7 out to z=1-2. At each epoch, there is a population of non-star-forming (quiescent) galaxies of high mass and high Sersic index. These galaxies might correspond to quenched galaxies and their average stellar mass increases with z. The starbursts ...
25 Years of the Hubble Space Telescope - Speaker
25 Years of the Hubble Space Telescope - Speaker

... Creation” in the Eagle Nebula. This image was the first Hubble image to fascinate the public, and still remains one of Hubble’s most popular images. It was obtained in 1995 with the Wide Field and Planetary Camera 2 (WFPC2). Inside the gaseous towers, which are light-years long, the interstellar gas ...
Chapter 10 Formation and evolution of the Local Group
Chapter 10 Formation and evolution of the Local Group

... Peebles, Tully and Shaya (2011) have produced a dynamical model of 28 galaxies (including the Galaxy) currently within 1.5 Mpc. The model does not show the assumed previous interaction between M 31 and M 33 (as suggested by the stellar and gaseous properties of the two galaxies and discussed shortly ...
Galaxy Sorting
Galaxy Sorting

... are probably so many dwarf galaxies that their combined mass probably exceeds that of all the  larger galaxies taken together. But their small size and dimness make them hard to detect and we  have only been able to discover them when they are relatively nearby.  Hubble based his classification sche ...
ASTRONOMIA SPAIN inglés.qxd
ASTRONOMIA SPAIN inglés.qxd

... This is the English edition of the book “Astronomía made in Spain”, an idea that materialized in 2009, the International Year of Astronomy. In order to celebrate that event, the Spanish Astronomical Society (Sociedad Española de Astronomía, SEA) had the idea of publishing a book summarising the hist ...
The environment of high-redshift AGN OLIMPIA JUDIT FOGASY
The environment of high-redshift AGN OLIMPIA JUDIT FOGASY

... appearance, one has to look at the various ways a galaxy can grow. According to the currently accepted cosmological model, the Λ Cold Dark Matter model (ΛCDM), structure formation started from primordial density fluctuations followed by gravitational collapse of dark matter, leading to the formation ...
The chemical enrichment of the ICM from hydrodynamical simulations
The chemical enrichment of the ICM from hydrodynamical simulations

... Chandra and XMM–Newton satellites are providing invaluable information on the thermodynamical properties of the intra–cluster medium (ICM) (Kaastra et al. 2008 - Chapter 9, this volume). These observations highlight that non–gravitational sources of energy, such as energy feedback from supernovae (S ...
Course Outline - Tony Bacigalupo
Course Outline - Tony Bacigalupo

... variable, you can tell its luminosity  You can observe its apparent brightness  Form its luminosity, you can determine the ...
Spring 2015 Mercury - Astronomical Society of the Pacific
Spring 2015 Mercury - Astronomical Society of the Pacific

... he most famous 11th-century comet was Halley’s Comet of 1066, which was linked to the Norman Conquest of England. But another comet of that century is linked to battles in both Scotland and Holland, and we are just three years away from its 1,000th anniversary. While the Battle of Hastings sealed th ...
Galaxies
Galaxies

... Eventually it was realized that quasar spectra were normal, but enormously redshifted ...
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Structure formation

In physical cosmology, structure formation refers to the formation of galaxies, galaxy clusters and larger structures from small early density fluctuations. The Universe, as is now known from observations of the cosmic microwave background radiation, began in a hot, dense, nearly uniform state approximately 13.8 billion years ago. However, looking in the sky today, we see structures on all scales, from stars and planets to galaxies and, on still larger scales still, galaxy clusters and sheet-like structures of galaxies separated by enormous voids containing few galaxies. Structure formation attempts to model how these structures formed by gravitational instability of small early density ripples.The modern Lambda-CDM model is successful at predicting the observed large-scale distribution of galaxies, clusters and voids; but on the scale of individual galaxies there are many complications due to highly nonlinear processes involving baryonic physics, gas heating and cooling, star formation and feedback. Understanding the processes of galaxy formation is a major topic of modern cosmology research, both via observations such as the Hubble Ultra-Deep Field and via large computer simulations.
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