Astronomy 401 Lecture 1 Overview of the Universe 1 Class overview
... has the same temperature as the surface of a star, and then it would emit as much light as it absorbs and glow as brightly as the stars. • Assumed that number density and mean luminosity of stars are constant throughout the universe; distant stars might be less numerous or less luminous than nearby ...
... has the same temperature as the surface of a star, and then it would emit as much light as it absorbs and glow as brightly as the stars. • Assumed that number density and mean luminosity of stars are constant throughout the universe; distant stars might be less numerous or less luminous than nearby ...
update : Feb.27,2014
... ionization levels similar to those produced by all the radiation coming from the sun," Inan* says. "When we put this information into our mathematical models it may provide us with important new insights about how the ionosphere behaves in response to sudden ionization changes.“*Umran Inan, professo ...
... ionization levels similar to those produced by all the radiation coming from the sun," Inan* says. "When we put this information into our mathematical models it may provide us with important new insights about how the ionosphere behaves in response to sudden ionization changes.“*Umran Inan, professo ...
Standard Set 2 - Atascadero High School
... visible. To discover what form this invisible (or “dark”) matter takes is one of the great goals of astrophysics. Section C Students know the evidence indicating that all elements with an atomic number greater than that of lithium have been formed by nuclear fusion in stars. Formation of the element ...
... visible. To discover what form this invisible (or “dark”) matter takes is one of the great goals of astrophysics. Section C Students know the evidence indicating that all elements with an atomic number greater than that of lithium have been formed by nuclear fusion in stars. Formation of the element ...
Astrophysics Presentation
... This is a wonderful opportunity for us to think about the assumptions we (and others) make all the time ...
... This is a wonderful opportunity for us to think about the assumptions we (and others) make all the time ...
Gresham Lecture, Wednesday 15 December 2010 Unsolved
... it by the huge number of neutrinos present in the Universe, we obtain a contribution to the total mass of the Universe which is slightly less than that from visible matter. As they are moving at the speed of light they form what is called “hot dark matter”. If there were too much hot dark matter it ...
... it by the huge number of neutrinos present in the Universe, we obtain a contribution to the total mass of the Universe which is slightly less than that from visible matter. As they are moving at the speed of light they form what is called “hot dark matter”. If there were too much hot dark matter it ...
A Cosmic End: From the Earth to the Universe
... Galaxy formation and evolution is a complex combination of hierarchical clustering, gas dissipation, merging, and secular evolution. Galaxies are tracers of cosmic evolution over the last 13 billion years. Galactic time scale is the combination of two clocks. One time scale is the cosmological one ( ...
... Galaxy formation and evolution is a complex combination of hierarchical clustering, gas dissipation, merging, and secular evolution. Galaxies are tracers of cosmic evolution over the last 13 billion years. Galactic time scale is the combination of two clocks. One time scale is the cosmological one ( ...
Olbers` Paradox - NMSU Astronomy
... most easily be dropped? Assumption 1) (homogeneity) has a considerable amount of observational evidence to back it up, and it would be pointless to regard assumption 4) as false, so these two assumptions should be retained. Assumption 2) could be dropped, as if the Universe is not unchanging, one co ...
... most easily be dropped? Assumption 1) (homogeneity) has a considerable amount of observational evidence to back it up, and it would be pointless to regard assumption 4) as false, so these two assumptions should be retained. Assumption 2) could be dropped, as if the Universe is not unchanging, one co ...
Unit 2 Lesson 1
... process of nuclear fusion. • It escapes in the form of light, other forms of radiation, heat, and wind. • Stars range in size from about the size of Earth to as much as 1,000 times the size of the sun. ...
... process of nuclear fusion. • It escapes in the form of light, other forms of radiation, heat, and wind. • Stars range in size from about the size of Earth to as much as 1,000 times the size of the sun. ...
DSST® ASTRONOMY EXAM INFORMATION
... 1. In the northern hemisphere, the vernal equinox is the position occupied by the Sun on the first day of a. summer b. fall c. spring d. winter 2. Which of the following is the best illustration of Newton's third law? a. A skater coasting across the ice b. The spinning of a top c. The swinging of a ...
... 1. In the northern hemisphere, the vernal equinox is the position occupied by the Sun on the first day of a. summer b. fall c. spring d. winter 2. Which of the following is the best illustration of Newton's third law? a. A skater coasting across the ice b. The spinning of a top c. The swinging of a ...
Slide 1
... constant, ρ is the energy density of the matter in the universe and c is the speed of light. The radius of curvature of space of the Einstein universe is equal to The Einstein universe is one of Friedmann's solutions to Einstein's field equation for dust with density ρ, cosmological constant ΛE, and ...
... constant, ρ is the energy density of the matter in the universe and c is the speed of light. The radius of curvature of space of the Einstein universe is equal to The Einstein universe is one of Friedmann's solutions to Einstein's field equation for dust with density ρ, cosmological constant ΛE, and ...
Training
... an accurate determination of the distance to the galaxy. The resulting distance to NGC 4414, 19.1 megaparsecs or about 60 million light-years, along with similarly determined distances to other nearby galaxies, contributes to astronomers' overall knowledge of the rate of expansion of the universe. T ...
... an accurate determination of the distance to the galaxy. The resulting distance to NGC 4414, 19.1 megaparsecs or about 60 million light-years, along with similarly determined distances to other nearby galaxies, contributes to astronomers' overall knowledge of the rate of expansion of the universe. T ...
Activity 2 The Signature of the Stars
... Figure 6 Cosmologists use a parameter called z to indicate redshift. The higher the value of z, the higher the redshift. ...
... Figure 6 Cosmologists use a parameter called z to indicate redshift. The higher the value of z, the higher the redshift. ...
Excerpt from Aristotle`s “On the Heavens”
... The substance of the heaven and stars we call ether, not because it blazes, owing to its fiery nature (as some explain the word, mistaking its nature, which is very far removed from fire), but because it is in continual motion,†1 revolving in a circle, being an element other than the four pure and ...
... The substance of the heaven and stars we call ether, not because it blazes, owing to its fiery nature (as some explain the word, mistaking its nature, which is very far removed from fire), but because it is in continual motion,†1 revolving in a circle, being an element other than the four pure and ...
The Hubble Space Telescope - the first 10 years
... Stars • Stars form from giant gas clouds floating in space • The cloud first starts to collapse due to gravity • When sub-clumps reach a sufficiently high density Nuclear fusion occurs bathing the region in radiation • This radiation blows away any remaining dust • Finally we’re left with a star cl ...
... Stars • Stars form from giant gas clouds floating in space • The cloud first starts to collapse due to gravity • When sub-clumps reach a sufficiently high density Nuclear fusion occurs bathing the region in radiation • This radiation blows away any remaining dust • Finally we’re left with a star cl ...
Historical Overview of the Universe
... of heavy elements, which are returned to the interstellar medium by stellar explosions and stellar winds. Galaxies were found to be “island universes.” It was recognized that they are generally receding from Earth in proportion to distance. At the same time, general relativistic world models predict ...
... of heavy elements, which are returned to the interstellar medium by stellar explosions and stellar winds. Galaxies were found to be “island universes.” It was recognized that they are generally receding from Earth in proportion to distance. At the same time, general relativistic world models predict ...
Unit 1: The Big Picture
... Made up of 200 billion stars, dust and gas Gases absorb light from stars and give a band of light in the sky – Difficult to see stars in other spiral arms – Scientists use radio & infrared waves to penetrate dust ...
... Made up of 200 billion stars, dust and gas Gases absorb light from stars and give a band of light in the sky – Difficult to see stars in other spiral arms – Scientists use radio & infrared waves to penetrate dust ...
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... body, the amount of surface area of the body and the surface temperature of the body. The body that emits the greatest amount of energy is a so called black body. Using Planck's Black Body Curve as a guide Dicke theorized that the Cosmic Background Radiation of the Big Bang should be about 3° above ...
... body, the amount of surface area of the body and the surface temperature of the body. The body that emits the greatest amount of energy is a so called black body. Using Planck's Black Body Curve as a guide Dicke theorized that the Cosmic Background Radiation of the Big Bang should be about 3° above ...
Name Section
... Doppler Shift and the Expanding Universe Your instructor will discuss the Doppler shift of light waves from a moving source. a) A stationery light source emits waves of light uniformly in all directions as shown in the diagram. How do the wavelengths of light from the right side of the diagram compa ...
... Doppler Shift and the Expanding Universe Your instructor will discuss the Doppler shift of light waves from a moving source. a) A stationery light source emits waves of light uniformly in all directions as shown in the diagram. How do the wavelengths of light from the right side of the diagram compa ...
Practice Questions for Final
... C. During the first 0.001 second after the Big Bang, particles and antiparticles were made in almost but not perfectly equal numbers. Everything annihilated except the very slight excess of matter particles. D. GUT theories predict that under the conditions that prevailed in the early universe, the ...
... C. During the first 0.001 second after the Big Bang, particles and antiparticles were made in almost but not perfectly equal numbers. Everything annihilated except the very slight excess of matter particles. D. GUT theories predict that under the conditions that prevailed in the early universe, the ...
DTU_9e_ch18 - University of San Diego Home Pages
... explosively in an event called the Big Bang. The Hubble law describes the ongoing expansion of the universe and the rate at which superclusters of galaxies move apart. The observable universe extends about 13.7 billion ly in every direction from Earth to what is called the cosmic light horizon. We c ...
... explosively in an event called the Big Bang. The Hubble law describes the ongoing expansion of the universe and the rate at which superclusters of galaxies move apart. The observable universe extends about 13.7 billion ly in every direction from Earth to what is called the cosmic light horizon. We c ...
A glance at the beginning of the Universe
... Edwin Hubble identified Cepheid variables in Andromeda Nebula. He proved conclusively that these nebulae were too distant to be part of the Milky Way and were, in fact, entire galaxies outside our own. ...
... Edwin Hubble identified Cepheid variables in Andromeda Nebula. He proved conclusively that these nebulae were too distant to be part of the Milky Way and were, in fact, entire galaxies outside our own. ...
Chapter 31 Galaxies & the Universe
... that the universe looks the same on large scales to all observers and that it has always looked that way ...
... that the universe looks the same on large scales to all observers and that it has always looked that way ...
Universe
The Universe is all of time and space and its contents. The Universe includes planets, stars, galaxies, the contents of intergalactic space, the smallest subatomic particles, and all matter and energy. The observable universe is about 28 billion parsecs (91 billion light-years) in diameter at the present time. The size of the whole Universe is not known and may be infinite. Observations and the development of physical theories have led to inferences about the composition and evolution of the Universe.Throughout recorded history, cosmologies and cosmogonies, including scientific models, have been proposed to explain observations of the Universe. The earliest quantitative geocentric models were developed by ancient Greek philosophers and Indian philosophers. Over the centuries, more precise astronomical observations led to Nicolaus Copernicus's heliocentric model of the Solar System and Johannes Kepler's improvement on that model with elliptical orbits, which was eventually explained by Isaac Newton's theory of gravity. Further observational improvements led to the realization that the Solar System is located in a galaxy composed of billions of stars, the Milky Way. It was subsequently discovered that our galaxy is just one of many. On the largest scales, it is assumed that the distribution of galaxies is uniform and the same in all directions, meaning that the Universe has neither an edge nor a center. Observations of the distribution of these galaxies and their spectral lines have led to many of the theories of modern physical cosmology. The discovery in the early 20th century that galaxies are systematically redshifted suggested that the Universe is expanding, and the discovery of the cosmic microwave background radiation suggested that the Universe had a beginning. Finally, observations in the late 1990s indicated the rate of the expansion of the Universe is increasing indicating that the majority of energy is most likely in an unknown form called dark energy. The majority of mass in the universe also appears to exist in an unknown form, called dark matter.The Big Bang theory is the prevailing cosmological model describing the development of the Universe. Space and time were created in the Big Bang, and these were imbued with a fixed amount of energy and matter; as space expands, the density of that matter and energy decreases. After the initial expansion, the Universe cooled sufficiently to allow the formation first of subatomic particles and later of simple atoms. Giant clouds of these primordial elements later coalesced through gravity to form stars. Assuming that the prevailing model is correct, the age of the Universe is measured to be 7001137990000000000♠13.799±0.021 billion years.There are many competing hypotheses about the ultimate fate of the Universe. Physicists and philosophers remain unsure about what, if anything, preceded the Big Bang. Many refuse to speculate, doubting that any information from any such prior state could ever be accessible. There are various multiverse hypotheses, in which some physicists have suggested that the Universe might be one among many universes that likewise exist.