Scale the Universe - Crystal Ball Science
... • Name the smallest things that you can think of… • What are some of the largest things you can think of? • What about the most distant object? Winter 2008 ...
... • Name the smallest things that you can think of… • What are some of the largest things you can think of? • What about the most distant object? Winter 2008 ...
A GMOS dissection of the line-of
... Our observations show that there is no large cluster in front of the quasar, but rather several smaller groups at different redshifts. Hard to tell if there is strong magnification present from current data. Statistical properties of high-z radio quasars may be more useful in determining importance ...
... Our observations show that there is no large cluster in front of the quasar, but rather several smaller groups at different redshifts. Hard to tell if there is strong magnification present from current data. Statistical properties of high-z radio quasars may be more useful in determining importance ...
A Brief History of Time - Stephen Hawking
... As far as Kepler was concerned, elliptical orbits were merely an ad hoc hypothesis, and a rather repugnant one at that, because ellipses were clearly less perfect than circles. Having discovered almost by accident that elliptical orbits fit the observations well, he could not reconcile them with his ...
... As far as Kepler was concerned, elliptical orbits were merely an ad hoc hypothesis, and a rather repugnant one at that, because ellipses were clearly less perfect than circles. Having discovered almost by accident that elliptical orbits fit the observations well, he could not reconcile them with his ...
Module1: Scale of the Universe
... (Optional)Discussion:#Problems#with#Parallax:# It&sounds&fairly&easy&to&measure&the&distance&to&another☆&just&make&two& measurements&of&its&position&six&months&apart.&& In&practice,&however,&it&is&very&difBicult.&The&Birst&successful&measurement&of&stellar& parallax&came&more&than&two&hundred&y ...
... (Optional)Discussion:#Problems#with#Parallax:# It&sounds&fairly&easy&to&measure&the&distance&to&another☆&just&make&two& measurements&of&its&position&six&months&apart.&& In&practice,&however,&it&is&very&difBicult.&The&Birst&successful&measurement&of&stellar& parallax&came&more&than&two&hundred&y ...
general relativity and gravitational waves
... When we draw spherical coordinates on a sphere, and follow two lines, that are perpendicular to the equation, in the direction of the North pole, we observe that two initial parallel lines meet at a point on the curved surface. The fifth postulate of Euclid does not hold for a curved space: parallel ...
... When we draw spherical coordinates on a sphere, and follow two lines, that are perpendicular to the equation, in the direction of the North pole, we observe that two initial parallel lines meet at a point on the curved surface. The fifth postulate of Euclid does not hold for a curved space: parallel ...
1957_boeke_cosmic view
... of 500 meters, to reduce the scale again to one-tenth the previous scale, we will have moved 450 meters, or ten times the length of our first jump. The next jump would be 4,500 meters, to a distance of 5,000 meters, etc. We soon find that we have started on a tremendous journey of exploration, and w ...
... of 500 meters, to reduce the scale again to one-tenth the previous scale, we will have moved 450 meters, or ten times the length of our first jump. The next jump would be 4,500 meters, to a distance of 5,000 meters, etc. We soon find that we have started on a tremendous journey of exploration, and w ...
Cosmic View The Universe in 40 Jumps
... of 500 meters, to reduce the scale again to one-tenth the previous scale, we will have moved 450 meters, or ten times the length of our first jump. The next jump would be 4,500 meters, to a distance of 5,000 meters, etc. We soon find that we have started on a tremendous journey of exploration, and w ...
... of 500 meters, to reduce the scale again to one-tenth the previous scale, we will have moved 450 meters, or ten times the length of our first jump. The next jump would be 4,500 meters, to a distance of 5,000 meters, etc. We soon find that we have started on a tremendous journey of exploration, and w ...
The quest for the size of the universe in early relativistic cosmology
... equations, formulated in 1917 by Einstein and by de Sitter, were the main focus of interest during the early phase of relativistic cosmology. These solutions represented by their intention a static universe with finite curvature radius. The Einstein universe was spherical and filled with matter, whe ...
... equations, formulated in 1917 by Einstein and by de Sitter, were the main focus of interest during the early phase of relativistic cosmology. These solutions represented by their intention a static universe with finite curvature radius. The Einstein universe was spherical and filled with matter, whe ...
View the pdf here
... but it is dedicated to von humboldt. he contrasts the positions of aristotle, bacon, hume, kant, bentham, and mill, for example. he quotes them. it is a defense of imagination, intuition, and improvisation in all the paths of human inquiry, including the sciences, and it is a reasoned defense by a c ...
... but it is dedicated to von humboldt. he contrasts the positions of aristotle, bacon, hume, kant, bentham, and mill, for example. he quotes them. it is a defense of imagination, intuition, and improvisation in all the paths of human inquiry, including the sciences, and it is a reasoned defense by a c ...
Chapter 15 THE MILKY WAY IN RELATION TO OTHER GALAXIES
... size is difficult. Although studies on photographic plates are available from the earliest days of photometry (de Vaucouleurs (1957) observed the LMC very early on in his studies and determined the exponential nature of its disk), the prime method today is the use of CCD’s behind small telescopes (o ...
... size is difficult. Although studies on photographic plates are available from the earliest days of photometry (de Vaucouleurs (1957) observed the LMC very early on in his studies and determined the exponential nature of its disk), the prime method today is the use of CCD’s behind small telescopes (o ...
1 Cosmology: a brief refresher course
... microwave background. Once we subtract off the dipole due to our motion through space, we find that the remaining background is very close to flat, with inhomogeneities only at the 10−5 level. • Direct observation evidence for homogeneity is harder to come by, but large-scale galaxy surveys find res ...
... microwave background. Once we subtract off the dipole due to our motion through space, we find that the remaining background is very close to flat, with inhomogeneities only at the 10−5 level. • Direct observation evidence for homogeneity is harder to come by, but large-scale galaxy surveys find res ...
The National Centre for Radio Astrophysics
... the neutral hydrogen distribution of the distant Universe, as well as physical conditions in the absorbing galaxies. Understanding conditions in such absorption-selected high-redshift galaxies is another area of research at NCRA-TIFR. Besides absorption studies to measure the gas temperature and met ...
... the neutral hydrogen distribution of the distant Universe, as well as physical conditions in the absorbing galaxies. Understanding conditions in such absorption-selected high-redshift galaxies is another area of research at NCRA-TIFR. Besides absorption studies to measure the gas temperature and met ...
Galaxy Sorting
... machine you can find. Once you have good copies, you may want to laminate them, or at least put them in plastic page protectors, so they can survive more than one class of students. · To help students visualize how an elliptical or spiral galaxy might appear to us when seen from different vantag ...
... machine you can find. Once you have good copies, you may want to laminate them, or at least put them in plastic page protectors, so they can survive more than one class of students. · To help students visualize how an elliptical or spiral galaxy might appear to us when seen from different vantag ...
Starburst Galaxies - Beck-Shop
... In those regions the massive hot young stars are extremely bright and outshine the far more numerous less massive stars. Few starforming regions are to be found in the remainder of the disk and so, despite there still being many stars in those regions, they appear dark in comparison with the arms. M ...
... In those regions the massive hot young stars are extremely bright and outshine the far more numerous less massive stars. Few starforming regions are to be found in the remainder of the disk and so, despite there still being many stars in those regions, they appear dark in comparison with the arms. M ...
Chapter 1: Introduction to Galaxies File - QMplus
... galaxies can be important. Galaxies can sometimes interact and even merge. Intergalactic gas, for example that found in clusters of galaxies, can be important. These various factors, and the feedback from one to another, mean that a number of important problems remain to be solved in extragalactic s ...
... galaxies can be important. Galaxies can sometimes interact and even merge. Intergalactic gas, for example that found in clusters of galaxies, can be important. These various factors, and the feedback from one to another, mean that a number of important problems remain to be solved in extragalactic s ...
2011-GravLens
... Gravitational lenses can be used as gravitational telescopes. The concentrated light from objects seen behind gravitational lenses makes very faint objects appear brighter, larger and therefore more easily studied. One of the most distant object in the universe was discovered by the gravitational le ...
... Gravitational lenses can be used as gravitational telescopes. The concentrated light from objects seen behind gravitational lenses makes very faint objects appear brighter, larger and therefore more easily studied. One of the most distant object in the universe was discovered by the gravitational le ...
A Brief History of Time
... outermost sphere carried the so-called fixed stars, which always stay in the same positions relative to each other but which rotate together across the sky. What lay beyond the last sphere was never made very clear, but it certainly was not part of mankind’s observable universe. Ptolemy’s model prov ...
... outermost sphere carried the so-called fixed stars, which always stay in the same positions relative to each other but which rotate together across the sky. What lay beyond the last sphere was never made very clear, but it certainly was not part of mankind’s observable universe. Ptolemy’s model prov ...
The Formation and Evolution of Massive Black Holes - Ira-Inaf
... referred to as active galactic nuclei, and the most powerful among them are known as quasars. Quasars are the most luminous stable sources in the whole universe, making them beacons in the early stages of galaxy assembly. Some powerful quasars have been detected at distances corresponding to a light ...
... referred to as active galactic nuclei, and the most powerful among them are known as quasars. Quasars are the most luminous stable sources in the whole universe, making them beacons in the early stages of galaxy assembly. Some powerful quasars have been detected at distances corresponding to a light ...
Part 9: Story of the Universe
... Finkelstein, S. L. et al. Nature 502, 524–527 (2013); see also Riecher 24 October 2013, Nature, 502, 459 Atoms to Astronomy ...
... Finkelstein, S. L. et al. Nature 502, 524–527 (2013); see also Riecher 24 October 2013, Nature, 502, 459 Atoms to Astronomy ...
Introduction to Dark Matter
... in the form of the Cosmic Microwave Background Radiation (CMBR; often referred to as the “afterglow” of Big Bang) which can be observed at T ≈ 2.73 K with radio telescopes. In order for astrophysical objects like galaxies, star clusters and stars to form, density fluctuations must have been present ...
... in the form of the Cosmic Microwave Background Radiation (CMBR; often referred to as the “afterglow” of Big Bang) which can be observed at T ≈ 2.73 K with radio telescopes. In order for astrophysical objects like galaxies, star clusters and stars to form, density fluctuations must have been present ...
The fate of black hole singularities and the parameters of the
... times for an astrophysical black hole and therefor, plausibly, beyond the scope of this paper, whatever new region of spacetime is traced by these diverging geodesics remains hidden behind the original horizon. Moreover, any observers in this new region see themselves to be in a region of spacetime ...
... times for an astrophysical black hole and therefor, plausibly, beyond the scope of this paper, whatever new region of spacetime is traced by these diverging geodesics remains hidden behind the original horizon. Moreover, any observers in this new region see themselves to be in a region of spacetime ...
Spacephysics - The summary
... the centre of star clusters and big, supermassive black holes in the centre of galaxies and quasars, being integral prognosed part of Space physics. Hundreds of black holes have since been found in the Milky Way, the origination of a black hole every l.000 years and the existence of about l0 million ...
... the centre of star clusters and big, supermassive black holes in the centre of galaxies and quasars, being integral prognosed part of Space physics. Hundreds of black holes have since been found in the Milky Way, the origination of a black hole every l.000 years and the existence of about l0 million ...
A Map of the Universe
... picture, at a scale of 1/108 , shows the entire Earth. The 14th picture, at a scale of 1/1014 , shows the entire Solar system. The 18th picture, at a scale of 1/1018 , includes α Centauri, The 22nd picture, at a scale of 1/1022 shows all of the Milky Way Galaxy. The 26th and last picture in the sequ ...
... picture, at a scale of 1/108 , shows the entire Earth. The 14th picture, at a scale of 1/1014 , shows the entire Solar system. The 18th picture, at a scale of 1/1018 , includes α Centauri, The 22nd picture, at a scale of 1/1022 shows all of the Milky Way Galaxy. The 26th and last picture in the sequ ...
Galaxy formation in the Planck cosmology - II. Star
... SFHs from the Millennium Simulation with observed ones from the VESPA algorithm as applied to the Sloan Digital Sky Survey 7 (SDSS-7) catalogue. The overall agreement is good, with both simulated and SDSS galaxies showing a steeper SFH with increased stellar mass. The SFHs of blue and red galaxies, ...
... SFHs from the Millennium Simulation with observed ones from the VESPA algorithm as applied to the Sloan Digital Sky Survey 7 (SDSS-7) catalogue. The overall agreement is good, with both simulated and SDSS galaxies showing a steeper SFH with increased stellar mass. The SFHs of blue and red galaxies, ...
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.