Cosmological Aspects of Nucleosynthesis
... The relative r-process and alpha-element abundances for metal-poor stars will constraint the yield for different stellar masses and associated mass cuts in SNe. Here are some thoughts by Freeman and Bland-Hawthorn (2002) The near-field universe is as important as the far-field universe for unders ...
... The relative r-process and alpha-element abundances for metal-poor stars will constraint the yield for different stellar masses and associated mass cuts in SNe. Here are some thoughts by Freeman and Bland-Hawthorn (2002) The near-field universe is as important as the far-field universe for unders ...
A generic relation between baryonic and radiative energy densities
... By using elementary astrophysical concepts, we show that for any self-luminous astrophysical object the ratio of radiation energy density inside the body (ρ r ) and the baryonic energy density (ρ 0 ) may be crudely approximated, in the Newtonian limit, as ρ r /ρ 0 ∝ GM/Rc2 , where G is constant of g ...
... By using elementary astrophysical concepts, we show that for any self-luminous astrophysical object the ratio of radiation energy density inside the body (ρ r ) and the baryonic energy density (ρ 0 ) may be crudely approximated, in the Newtonian limit, as ρ r /ρ 0 ∝ GM/Rc2 , where G is constant of g ...
- Fermi Gamma-ray Space Telescope
... Discovered in 1965 by Arno Penzias and Robert Wilson who were working at Bell Labs ...
... Discovered in 1965 by Arno Penzias and Robert Wilson who were working at Bell Labs ...
STATES OF MATTER
... If the gas is made up of particles which carry an electric charge (“ionized particles”), but the entire gas as a whole has no electric charge, and if the density is not too high, then we can get ...
... If the gas is made up of particles which carry an electric charge (“ionized particles”), but the entire gas as a whole has no electric charge, and if the density is not too high, then we can get ...
Sky News – March 2015 The Realm of the Galaxies
... west with the onset of darkness, bringing the spring constellations of Leo, Virgo, Coma Bernices and Ursa Major into prominence. It is within these that hosts of galaxies reside. The North Galactic Pole, the point in the sky directly over the centre of our galaxy, is in the constellation Coma Bernic ...
... west with the onset of darkness, bringing the spring constellations of Leo, Virgo, Coma Bernices and Ursa Major into prominence. It is within these that hosts of galaxies reside. The North Galactic Pole, the point in the sky directly over the centre of our galaxy, is in the constellation Coma Bernic ...
Universe Standards - Harvard
... to form countless trillions of stars. Billions of galaxies, each of which is a gravitationally bound cluster of billions of stars, now form most of the visible mass in the universe.” 4. Component Concept: The universe began as being very uniform and has gotten more “lumpy” with time. i. matter was n ...
... to form countless trillions of stars. Billions of galaxies, each of which is a gravitationally bound cluster of billions of stars, now form most of the visible mass in the universe.” 4. Component Concept: The universe began as being very uniform and has gotten more “lumpy” with time. i. matter was n ...
Other Galaxies, their Distances, and the Expansion of the Universe
... ~70 km/s/Mpc Velocity that the galaxy is moving away ...
... ~70 km/s/Mpc Velocity that the galaxy is moving away ...
Astronomy and Cosmology - spring 2003 - final exam
... B) This "particle" must have been a photon or quantum of electromagnetic radiation of very high energy in order to have traveled this fast. C) This result is acceptable since atomic particles can travel this fast, whereas larger bodies are limited to 3 × 105 m s1. D) This is an acceptable result fo ...
... B) This "particle" must have been a photon or quantum of electromagnetic radiation of very high energy in order to have traveled this fast. C) This result is acceptable since atomic particles can travel this fast, whereas larger bodies are limited to 3 × 105 m s1. D) This is an acceptable result fo ...
Introduction to Galaxies and Cosmology Exercises 2
... redshift of z = 0.03 with a standard deviation of σz = 0.004. H0 = 70km/s/Mpc. a) Estimate the dynamical mass of the cluster. b) Estimate the mass of all the galaxies taken together by assuming that they follow a luminosity function: dN ∝ L−2 dL between MV = −12 and -22, and that they have an averag ...
... redshift of z = 0.03 with a standard deviation of σz = 0.004. H0 = 70km/s/Mpc. a) Estimate the dynamical mass of the cluster. b) Estimate the mass of all the galaxies taken together by assuming that they follow a luminosity function: dN ∝ L−2 dL between MV = −12 and -22, and that they have an averag ...
Super Giant
... Explain why the moon revolves around the Earth instead of the Sun. Even though the moon is larger than Pluto, which DOES revolve around the Sun, The moon revolves around the Earth because it is CLOSER to the Earth. The two factors that determine the force of gravity are mass and distance. What relat ...
... Explain why the moon revolves around the Earth instead of the Sun. Even though the moon is larger than Pluto, which DOES revolve around the Sun, The moon revolves around the Earth because it is CLOSER to the Earth. The two factors that determine the force of gravity are mass and distance. What relat ...
Summation Packet KEY
... 21. Some stars that are in the night’s sky have already died. Explain why we can still see them, even if they exploded thousands of years ago. The stars are so far away that it takes millions of years for the light to reach Earth. 22. The picture to the right is of a boat using its foghorn. Describe ...
... 21. Some stars that are in the night’s sky have already died. Explain why we can still see them, even if they exploded thousands of years ago. The stars are so far away that it takes millions of years for the light to reach Earth. 22. The picture to the right is of a boat using its foghorn. Describe ...
PC2491 Examples 2
... of the Sun and (r) is the angular velocity at radius r. An H1 cloud in the galactic plane at l=30o is observed to have a velocity relative to the local standard of rest of +80 km s-1. Assume the galactic rotation curve is flat with an amplitude of 220 km s-1 , and that Ro = 8.2 kpc and estimate the ...
... of the Sun and (r) is the angular velocity at radius r. An H1 cloud in the galactic plane at l=30o is observed to have a velocity relative to the local standard of rest of +80 km s-1. Assume the galactic rotation curve is flat with an amplitude of 220 km s-1 , and that Ro = 8.2 kpc and estimate the ...
Summer 2013, Vol. 2, No. 2 - CAAUL
... The session on cosmology was mostly devoted to theoretical aspects. In this sense it was not fully representative of current research in Portugal, where the field of observational cosmology has been growing. Indeed, there are Portuguese researchers involved in the recent results of the Planck missio ...
... The session on cosmology was mostly devoted to theoretical aspects. In this sense it was not fully representative of current research in Portugal, where the field of observational cosmology has been growing. Indeed, there are Portuguese researchers involved in the recent results of the Planck missio ...
PHYS 390 Lecture 31 - Kinematics of galaxies 31
... throughout the disk, only (8 / 25)2 = 10% of it would lie within Ro = 8 kpc. This is our first hint that there is perhaps 10 times as much "dark matter" as there is visible matter. For the Milky Way as a whole, the measured tangential velocities are drawn below. The vertical bars indicate the typica ...
... throughout the disk, only (8 / 25)2 = 10% of it would lie within Ro = 8 kpc. This is our first hint that there is perhaps 10 times as much "dark matter" as there is visible matter. For the Milky Way as a whole, the measured tangential velocities are drawn below. The vertical bars indicate the typica ...
Slide 1
... of 100-200 Mpc, but no sign of structure on a larger scale than that. The decreasing density of galaxies at the farthest distances is due to the difficulty of observing them. ...
... of 100-200 Mpc, but no sign of structure on a larger scale than that. The decreasing density of galaxies at the farthest distances is due to the difficulty of observing them. ...
Galaxies - senwiki
... -So what is a black hole? A black hole is a region of space where gravity is so strong that nothing, not even light, can escape. -Why? Black holes have extremely strong gravitational pulls. They can pull in stars and accumulate the mass of the stars. -Where are black holes located? Astronomers belie ...
... -So what is a black hole? A black hole is a region of space where gravity is so strong that nothing, not even light, can escape. -Why? Black holes have extremely strong gravitational pulls. They can pull in stars and accumulate the mass of the stars. -Where are black holes located? Astronomers belie ...
distance to the centre of the Milky Way.
... In ~1900, “Universe” = the distribution of stars within which we find ourselves (i.e. the Milky Way). It was believed to lie in a vast (perhaps infinite) void. ...
... In ~1900, “Universe” = the distribution of stars within which we find ourselves (i.e. the Milky Way). It was believed to lie in a vast (perhaps infinite) void. ...
Lambda-CDM model
The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a parametrization of the Big Bang cosmological model in which the universe contains a cosmological constant, denoted by Lambda (Greek Λ), associated with dark energy, and cold dark matter (abbreviated CDM). It is frequently referred to as the standard model of Big Bang cosmology, because it is the simplest model that provides a reasonably good account of the following properties of the cosmos: the existence and structure of the cosmic microwave background the large-scale structure in the distribution of galaxies the abundances of hydrogen (including deuterium), helium, and lithium the accelerating expansion of the universe observed in the light from distant galaxies and supernovaeThe model assumes that general relativity is the correct theory of gravity on cosmological scales.It emerged in the late 1990s as a concordance cosmology, after a period of time when disparate observed properties of the universe appeared mutually inconsistent, and there was no consensus on the makeup of the energy density of the universe.The ΛCDM model can be extended by adding cosmological inflation, quintessence and other elements that are current areas of speculation and research in cosmology.Some alternative models challenge the assumptions of the ΛCDM model. Examples of these are modified Newtonian dynamics, modified gravity and theories of large-scale variations in the matter density of the universe.