The phenomena of astrophysical masers are not new by any means
... phase. When the scattering in the medium is very strong it can provide feedback, though it is incoherent and intensity based rather than field-based. When the large path length of the scattered photons is coupled with the already large path length of the medium substantial gain may be recorded. The ...
... phase. When the scattering in the medium is very strong it can provide feedback, though it is incoherent and intensity based rather than field-based. When the large path length of the scattered photons is coupled with the already large path length of the medium substantial gain may be recorded. The ...
Lecture5 - Tufts Institute of Cosmology
... Re-observe those stars night after night Plot magnitude against time of observation Get period Deduce luminosity Determine distance modulus, then distance ...
... Re-observe those stars night after night Plot magnitude against time of observation Get period Deduce luminosity Determine distance modulus, then distance ...
PDF version - Caltech Astronomy
... quasars or gamma-ray bursts if you didn’t understand the physical processes at work? Genuine astrophysical understanding required a completely different set of tools: theoretical tools. Isaac Newton’s discoveries of the laws of motion and gravitation were of a different kind from those of Kepler and ...
... quasars or gamma-ray bursts if you didn’t understand the physical processes at work? Genuine astrophysical understanding required a completely different set of tools: theoretical tools. Isaac Newton’s discoveries of the laws of motion and gravitation were of a different kind from those of Kepler and ...
This document was created for people who do not have access to
... represent temperature, in this case, the temperature of the light detected by the WMAP space craft. WMAP views the sky with microwave eyes - the colors represent a range of temperatures of very low energy. This low energy light is all around us, leftover from the Big Bang. ...
... represent temperature, in this case, the temperature of the light detected by the WMAP space craft. WMAP views the sky with microwave eyes - the colors represent a range of temperatures of very low energy. This low energy light is all around us, leftover from the Big Bang. ...
Chapter 12 Our Place in the Universe
... The Universe as a perfect (black-body) radiator at 2.7 K This question is about the temperature of the Universe and the radiation that has filled it since neutral atoms were first produced. Plasma absorbs photons It is thought that the early Universe was too hot for electrons and protons to combine ...
... The Universe as a perfect (black-body) radiator at 2.7 K This question is about the temperature of the Universe and the radiation that has filled it since neutral atoms were first produced. Plasma absorbs photons It is thought that the early Universe was too hot for electrons and protons to combine ...
Our Universe - E Natural Health Center
... The big-bang model is based on two assumptions. The first is that Albert Einstein's general theory of relativity correctly describes the gravitational interaction of all matter. The second assumption, called the cosmological principle, states that an observer's view of the universe depends neither o ...
... The big-bang model is based on two assumptions. The first is that Albert Einstein's general theory of relativity correctly describes the gravitational interaction of all matter. The second assumption, called the cosmological principle, states that an observer's view of the universe depends neither o ...
Slides
... Effective Temperature Emission from most astronomical sources is only roughly described by the Planck function (if at all). For a source with a bolometric flux F, define the effective temperature Te via: ...
... Effective Temperature Emission from most astronomical sources is only roughly described by the Planck function (if at all). For a source with a bolometric flux F, define the effective temperature Te via: ...
Big Bang and Beyond
... • Many more amazing “coincidences” that make life possible have been discovered – The composition of our sun is just right, the distance of the Earth to the sun is just right, the size of the Earth is just right, the orbit of the Earth is just right, the size of our moon is just right and even the g ...
... • Many more amazing “coincidences” that make life possible have been discovered – The composition of our sun is just right, the distance of the Earth to the sun is just right, the size of the Earth is just right, the orbit of the Earth is just right, the size of our moon is just right and even the g ...
May 2009 Tz 2
... Observations of the night sky indicate that there are many regions of the universe that do not contain any stars. ...
... Observations of the night sky indicate that there are many regions of the universe that do not contain any stars. ...
Slides - Physics at SMU
... Empty Space is a normally perceived as being a vacuum void of energy but as special relativity tells us a vaccum is actually the lowest energy state possible. (a very different definition from "empty".) Even at this low energy state you still have some (even if its very small) energy that accumulat ...
... Empty Space is a normally perceived as being a vacuum void of energy but as special relativity tells us a vaccum is actually the lowest energy state possible. (a very different definition from "empty".) Even at this low energy state you still have some (even if its very small) energy that accumulat ...
G485 5.5.1 Structure of the Universe
... Interpret Olber’s paradox to explain why it suggests that the model of an infinite, static universe is incorrect. ...
... Interpret Olber’s paradox to explain why it suggests that the model of an infinite, static universe is incorrect. ...
Galaxies
... protogalactic clouds that were able to cool and form stars before gas settled into a disk ...
... protogalactic clouds that were able to cool and form stars before gas settled into a disk ...
Lecture2 - UCSB Physics
... How big? Hubble discovers the “realm of the nebulae” • Using the Cepheid distance Hubble concludes that M31 is 750 kpc away (15 times the size of the Milky Way) • Thus, the size of M31 is 70 kpc, larger than our own Milky Way. • The same is true for billions of galaxies that populate the univers ...
... How big? Hubble discovers the “realm of the nebulae” • Using the Cepheid distance Hubble concludes that M31 is 750 kpc away (15 times the size of the Milky Way) • Thus, the size of M31 is 70 kpc, larger than our own Milky Way. • The same is true for billions of galaxies that populate the univers ...
What kind of stuff
... How big? Hubble discovers the “realm of the nebulae” • Using the Cepheid distance Hubble concludes that M31 is 750 kpc away (15 times the size of the Milky Way) • Thus, the size of M31 is 70 kpc, larger than our own Milky Way. • The same is true for billions of galaxies that populate the universe! ...
... How big? Hubble discovers the “realm of the nebulae” • Using the Cepheid distance Hubble concludes that M31 is 750 kpc away (15 times the size of the Milky Way) • Thus, the size of M31 is 70 kpc, larger than our own Milky Way. • The same is true for billions of galaxies that populate the universe! ...
galaxy - 106Thursday130-430
... Cosmic Rays - the field is weak being only about 1/50 000 of the strength of the Earth’s magnetic field at the surface, but it influences the motion of charged particles in the galaxy. ...
... Cosmic Rays - the field is weak being only about 1/50 000 of the strength of the Earth’s magnetic field at the surface, but it influences the motion of charged particles in the galaxy. ...
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.