How do the most massive galaxies constrain theories of
... o CDM-based models of galaxy formation that produce reasonable agreement with the z=0 stellar mass function form enough massive galaxies at high z<2 o But default models do not produce enough massive red galaxies, especially at high redshift, because of continuous low level star formation. need a ne ...
... o CDM-based models of galaxy formation that produce reasonable agreement with the z=0 stellar mass function form enough massive galaxies at high z<2 o But default models do not produce enough massive red galaxies, especially at high redshift, because of continuous low level star formation. need a ne ...
Galaxy Hunters Article, Cosmology Information, First Star Facts
... Dark matter, moreover, answered a key riddle of galaxy formation: how the universe changed from a smooth, hot soup of particles into a jumble of galaxies and galaxy clusters. There had to be some lumps in the first place. By itself, ordinary matter—protons, electrons, and neutrons—couldn't provide t ...
... Dark matter, moreover, answered a key riddle of galaxy formation: how the universe changed from a smooth, hot soup of particles into a jumble of galaxies and galaxy clusters. There had to be some lumps in the first place. By itself, ordinary matter—protons, electrons, and neutrons—couldn't provide t ...
Astronomy 21 – Test 2 – Answers
... may add a greenish/yellowish shimmer (and if Carbon was present you’d see purple). But in star forming regions there are only small traces of these elements.] ...
... may add a greenish/yellowish shimmer (and if Carbon was present you’d see purple). But in star forming regions there are only small traces of these elements.] ...
Multiple Choice, continued
... • Many of the modern names we use for the constellations come from Latin. • Some constellations are named for real or imaginary animals, such as Ursa Major (the great bear) or ancient gods or legendary heroes, such as Hercules or Orion. ...
... • Many of the modern names we use for the constellations come from Latin. • Some constellations are named for real or imaginary animals, such as Ursa Major (the great bear) or ancient gods or legendary heroes, such as Hercules or Orion. ...
Correct answers shown in boldface. Be sure to write your name and
... Correct answers shown in boldface. Be sure to write your name and student ID number on the first blank at the bottom of the form, the exam number on the second (subject) one, and your section number (7 for 11:00, 8 for 12:00) in the "period" one. If you need to erase an answer, please do so carefull ...
... Correct answers shown in boldface. Be sure to write your name and student ID number on the first blank at the bottom of the form, the exam number on the second (subject) one, and your section number (7 for 11:00, 8 for 12:00) in the "period" one. If you need to erase an answer, please do so carefull ...
Stars, Galaxies, and the Universe Section 3 Stars, Galaxies, and the
... • Binary stars are pairs of stars that revolve around each other and are held together by gravity. The center of mass, or barycenter, is somewhere between the two stars. • In star systems that have more than two stars, two stars may revolve rapidly around a common barycenter, while a third star revo ...
... • Binary stars are pairs of stars that revolve around each other and are held together by gravity. The center of mass, or barycenter, is somewhere between the two stars. • In star systems that have more than two stars, two stars may revolve rapidly around a common barycenter, while a third star revo ...
Time From the Perspective of a Particle Physicist
... Cosmology. Hubble law Universe is expanding, gives universe’s age, depends on Hubble “constant” changes with time. Closed universe has gravity slowing the expansion so it starts to contract. Open universe expands forever. Early universe was very hot and when matter was created. First electrons, pr ...
... Cosmology. Hubble law Universe is expanding, gives universe’s age, depends on Hubble “constant” changes with time. Closed universe has gravity slowing the expansion so it starts to contract. Open universe expands forever. Early universe was very hot and when matter was created. First electrons, pr ...
ISP 205: Visions of the Universe
... — It rotates on its axis once a day and orbits the Sun at a distance of 1 AU = 150 million km • How is our solar system moving in the Milky Way Galaxy? — Stars in the Local Neighborhood move randomly relative to one another and orbit the center of the Milky Way in about 230 million years ...
... — It rotates on its axis once a day and orbits the Sun at a distance of 1 AU = 150 million km • How is our solar system moving in the Milky Way Galaxy? — Stars in the Local Neighborhood move randomly relative to one another and orbit the center of the Milky Way in about 230 million years ...
E1 Introduction to the universe
... evidence that lots of ordinary matter does exist in these groupings. These can be thought of as low-mass failed stars or high-mass planets. They could even be black holes. These would produce little or no light. some fundamental particles (neutrinos) are known to exist in huge numbers. It is not kno ...
... evidence that lots of ordinary matter does exist in these groupings. These can be thought of as low-mass failed stars or high-mass planets. They could even be black holes. These would produce little or no light. some fundamental particles (neutrinos) are known to exist in huge numbers. It is not kno ...
Homework #2 1. There are two ways to estimate the energy carried
... temperature so assume that Lr /Mr ∼ constant, independent of position in the star. In the rest of this problem, we will derive the KH contraction of a radiative star. Assume for simplicity that electron scattering dominates the opacity of the star. d) Derive R(t,M) for radiative stars undergoing KH ...
... temperature so assume that Lr /Mr ∼ constant, independent of position in the star. In the rest of this problem, we will derive the KH contraction of a radiative star. Assume for simplicity that electron scattering dominates the opacity of the star. d) Derive R(t,M) for radiative stars undergoing KH ...
Spiral Galaxies - Astronomy Centre
... • Spiral disks are relatively blue due to light from hot, massive, young stars • Elliptical galaxies are relatively red due to the dominant population of older, lower-mass stars ...
... • Spiral disks are relatively blue due to light from hot, massive, young stars • Elliptical galaxies are relatively red due to the dominant population of older, lower-mass stars ...
A Universe of Galaxies - Pennsylvania State University
... What can outshine ~1000 supernovae for millions of years, and be just slightly larger than our Solar System? Theoretically, not much – only a very, very big black hole. • Start with a black hole with a mass of 10,000,000,000 Mʘ • Have a star come close enough to be tidally disrupted • Have the mater ...
... What can outshine ~1000 supernovae for millions of years, and be just slightly larger than our Solar System? Theoretically, not much – only a very, very big black hole. • Start with a black hole with a mass of 10,000,000,000 Mʘ • Have a star come close enough to be tidally disrupted • Have the mater ...
exploring the solar system, the galaxies, and the
... specific Georgia Performance Standards related to Astronomy for grades 2, 4, and 6. Read these standards below, and select at least two topics for which you want to find more resources, both for your own learning and to use in your classroom. On the Amazing Space site, select “For Educators and Deve ...
... specific Georgia Performance Standards related to Astronomy for grades 2, 4, and 6. Read these standards below, and select at least two topics for which you want to find more resources, both for your own learning and to use in your classroom. On the Amazing Space site, select “For Educators and Deve ...
Link again
... The Big Bang is the cosmic explosion that may have begun the present universe and started the expansion of space. The universe appears to be expanding. Many astronomers assume that this means that the universe has expanded from the explosion of an infinitely dense beginning point. The galaxies thems ...
... The Big Bang is the cosmic explosion that may have begun the present universe and started the expansion of space. The universe appears to be expanding. Many astronomers assume that this means that the universe has expanded from the explosion of an infinitely dense beginning point. The galaxies thems ...
chap8 (WP)
... Now, it is incorrect to assume that H is a constant, but the results of Example 8.4 are not far off. Correcting for the change in H over time, we find that the age of the universe is approximately (2/3)H -1 , rather than just H -1 . So, based on the observed value of the Hubble parameter, we predict ...
... Now, it is incorrect to assume that H is a constant, but the results of Example 8.4 are not far off. Correcting for the change in H over time, we find that the age of the universe is approximately (2/3)H -1 , rather than just H -1 . So, based on the observed value of the Hubble parameter, we predict ...
1. setting the scene 2. the cosmic dark ages and the first stars
... from gamma rays to radio frequencies, it has become possible to piece together the past history of the Universe and make an educated guess as to its future destiny. This ‘standard model’ of cosmology is illustrated in Figure 1. Our Universe began 13.7 billion years ago, in an event whose popular nam ...
... from gamma rays to radio frequencies, it has become possible to piece together the past history of the Universe and make an educated guess as to its future destiny. This ‘standard model’ of cosmology is illustrated in Figure 1. Our Universe began 13.7 billion years ago, in an event whose popular nam ...
Lecture Notes – Galaxies
... Thus for a z = 4.0 quasar, the Lyman-α line of hydrogen will be redshifted from 121.5 nm to 607.5 nm; its recession velocity is 0.923c and its distance is 2 880 Mpc (H=50 km/s Mpc−1 ). Quasars are variable on time-scales of days to months which indicates that they are very small ( < 1 light month or ...
... Thus for a z = 4.0 quasar, the Lyman-α line of hydrogen will be redshifted from 121.5 nm to 607.5 nm; its recession velocity is 0.923c and its distance is 2 880 Mpc (H=50 km/s Mpc−1 ). Quasars are variable on time-scales of days to months which indicates that they are very small ( < 1 light month or ...
Quasars - Ann Arbor Earth Science
... superluminal sources - radio sources which show internal motions (for example, increasing separation between the core and a knot in the jet) which appears faster than the speed of light in our frame of reference. The data are consistent with this being a transformation effect from seeing jets movin ...
... superluminal sources - radio sources which show internal motions (for example, increasing separation between the core and a knot in the jet) which appears faster than the speed of light in our frame of reference. The data are consistent with this being a transformation effect from seeing jets movin ...
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.