The Milky Way and Dark Matter
... of matter in the Universe is the normal matter that we are made of and another 23% is what we refer to as dark matter. There is thought to be something else in the Universe that makes up the remaining 72%, dark energy. We will have to leave our lessons about dark energy for the future as scientists ...
... of matter in the Universe is the normal matter that we are made of and another 23% is what we refer to as dark matter. There is thought to be something else in the Universe that makes up the remaining 72%, dark energy. We will have to leave our lessons about dark energy for the future as scientists ...
PH607lec07
... in heavy elements, having been created before the interstellar gas had been seriously polluted with elements heavier than helium. A good view of the central bulge of our Galaxy is given by the nearinfrared picture below, which also shows the disk extending to either side. The picture was obtained us ...
... in heavy elements, having been created before the interstellar gas had been seriously polluted with elements heavier than helium. A good view of the central bulge of our Galaxy is given by the nearinfrared picture below, which also shows the disk extending to either side. The picture was obtained us ...
The nature of the faint galaxies in the Hubble Deep Field
... appear to have statistical validity over the range 0.I
... appear to have statistical validity over the range 0.I
Gravitational waves - LIGO
... eclipse of 1919 by Sir Arthur Eddington, when the Sun was silhouetted against the Hyades star cluster ...
... eclipse of 1919 by Sir Arthur Eddington, when the Sun was silhouetted against the Hyades star cluster ...
Document
... – measurement of L depends on distance (often estimated from the redshift z) – need for representative samples → large volume (but not too large as the function evolves with time…) – L depends on the chosen filter and shift with z (k-correction) – Malmquist bias → difficulty to determine Φ at low L ...
... – measurement of L depends on distance (often estimated from the redshift z) – need for representative samples → large volume (but not too large as the function evolves with time…) – L depends on the chosen filter and shift with z (k-correction) – Malmquist bias → difficulty to determine Φ at low L ...
Predicting the CIB-φ contamination in the cross
... cosmic microwave background (CMB) lensing potential (φ). The cross-correlation of these two probes of the large-scale structures in the Universe is a powerful tool for testing cosmological models, especially in the context of the difference between galaxy clusters and CMB for the best-fitting cosmolo ...
... cosmic microwave background (CMB) lensing potential (φ). The cross-correlation of these two probes of the large-scale structures in the Universe is a powerful tool for testing cosmological models, especially in the context of the difference between galaxy clusters and CMB for the best-fitting cosmolo ...
Word doc - UC-HiPACC - University of California, Santa Cruz
... Astronomers have long known that the Milky Way is a spiral galaxy. But how did our home galaxy get its beautiful spiral arms? A simulation run on the GreenPlanet supercomputer cluster at the University of California, Irvine suggests its spiral structure may have been triggered by an act of cosmic vi ...
... Astronomers have long known that the Milky Way is a spiral galaxy. But how did our home galaxy get its beautiful spiral arms? A simulation run on the GreenPlanet supercomputer cluster at the University of California, Irvine suggests its spiral structure may have been triggered by an act of cosmic vi ...
1. Seyfert Galaxies
... unification. X-ray evidence, where available, supports the unified picture: radio galaxies show evidence of obscuration from a torus, while quasars do not The population of radio galaxies is completely dominated by lowluminosity, low-excitation objects. there is no evidence for a torus in these obje ...
... unification. X-ray evidence, where available, supports the unified picture: radio galaxies show evidence of obscuration from a torus, while quasars do not The population of radio galaxies is completely dominated by lowluminosity, low-excitation objects. there is no evidence for a torus in these obje ...
Lab 15 How Many Galaxies Are There in the
... cover the whole sky. 6. Take a look at the image of the Hubble Deep Field given to you by your TA. Almost every one of the objects you see in this picture is a distant galaxy. Count up all the galaxies in each section then add them up to get an estimate of the number of galaxies in this one field. A ...
... cover the whole sky. 6. Take a look at the image of the Hubble Deep Field given to you by your TA. Almost every one of the objects you see in this picture is a distant galaxy. Count up all the galaxies in each section then add them up to get an estimate of the number of galaxies in this one field. A ...
Globular Clusters - University of Dayton
... Turn Off - As the hydrogen fuel in a star's core runs out the core begins to collapse due to gravity and the star moves away from the main sequence. At the turn off nearly all the central fuel is gone. Red Giant Branch - When the central fuel is gone, hydrogen starts to burn in an envelope around a ...
... Turn Off - As the hydrogen fuel in a star's core runs out the core begins to collapse due to gravity and the star moves away from the main sequence. At the turn off nearly all the central fuel is gone. Red Giant Branch - When the central fuel is gone, hydrogen starts to burn in an envelope around a ...
The age of elliptical galaxies and bulges in a merger model The age
... relationship between the strength of the Mg II index at the centre of ellipticals and their central velocity dispersions, (1. Galaxies show a mean scatter of only 0.025 mag in Mg II, versus a full range of nearly 0.35 mag in Mg II. This observed scatter sets an upper limit of 15 per cent on the rms ...
... relationship between the strength of the Mg II index at the centre of ellipticals and their central velocity dispersions, (1. Galaxies show a mean scatter of only 0.025 mag in Mg II, versus a full range of nearly 0.35 mag in Mg II. This observed scatter sets an upper limit of 15 per cent on the rms ...
Weak gravitational lensing
While the presence of any mass bends the path of light passing near it, this effect rarely produces the giant arcs and multiple images associated with strong gravitational lensing. Most lines of sight in the universe are thoroughly in the weak lensing regime, in which the deflection is impossible to detect in a single background source. However, even in these cases, the presence of the foreground mass can be detected, by way of a systematic alignment of background sources around the lensing mass. Weak gravitational lensing is thus an intrinsically statistical measurement, but it provides a way to measure the masses of astronomical objects without requiring assumptions about their composition or dynamical state.