Active Galactic Nuclei
... According to the Hubble Law, the space between the galaxies is constantly increasing, with Velocity = H0 D istance ...
... According to the Hubble Law, the space between the galaxies is constantly increasing, with Velocity = H0 D istance ...
LAST YEAR`S EXAM
... Using determine the current energy density in the CMB in terms of the critical density (i.e. determine !rad). Given that the current baryon density is !B=0.02h-2 , determine the ratio between between the number densities of photons and baryons. (8 marks) If the Universe is 4x1017 seconds old, determ ...
... Using determine the current energy density in the CMB in terms of the critical density (i.e. determine !rad). Given that the current baryon density is !B=0.02h-2 , determine the ratio between between the number densities of photons and baryons. (8 marks) If the Universe is 4x1017 seconds old, determ ...
final review sheet
... 3) If the distance between the Sun and the Earth increased by a factor of 2, the Sun’s luminosity would decrease by a factor of 4. 4) Pre-main sequence stars release energy by nuclear reactions which turn hydrogen into helium. 5) Astronomers can determine the age of clusters by looking at the distri ...
... 3) If the distance between the Sun and the Earth increased by a factor of 2, the Sun’s luminosity would decrease by a factor of 4. 4) Pre-main sequence stars release energy by nuclear reactions which turn hydrogen into helium. 5) Astronomers can determine the age of clusters by looking at the distri ...
Chapter 1 Our Place in the Universe
... A great island of stars in space, all held together by gravity and orbiting a common center ...
... A great island of stars in space, all held together by gravity and orbiting a common center ...
Ch. 26.5: The Expanding Universe
... & cannot be detected Exerts gravitational force on visible matter Universe may be 90% + dark matter Why do we think Dark Matter exists? Galaxies are accelerating faster than they should be (based on the observable matter in the Universe). The acceleration due to gravity does not match up with the am ...
... & cannot be detected Exerts gravitational force on visible matter Universe may be 90% + dark matter Why do we think Dark Matter exists? Galaxies are accelerating faster than they should be (based on the observable matter in the Universe). The acceleration due to gravity does not match up with the am ...
Class 28, 27 July
... • Nuclei try to collapse (gravity), photons push back (pressure) • This leads to OSCILLATIONS! • Size of oscillations measures geometry of universe (know physical size, angle, so can measure geometry) ...
... • Nuclei try to collapse (gravity), photons push back (pressure) • This leads to OSCILLATIONS! • Size of oscillations measures geometry of universe (know physical size, angle, so can measure geometry) ...
AV_Paper1_TheAgeOfTheUniverse
... “Since the beginning of time,” is a hackneyed phrase, attached with some arbitrary subject, that looks to exaggerate any issue its paired with. Although the use of the phrase highlights an individual’s vague grasp on the depth of time and use of uninspired hyperbole, one could find it surprising th ...
... “Since the beginning of time,” is a hackneyed phrase, attached with some arbitrary subject, that looks to exaggerate any issue its paired with. Although the use of the phrase highlights an individual’s vague grasp on the depth of time and use of uninspired hyperbole, one could find it surprising th ...
Wh t i C l ? What is Cosmology?
... (does work, but does not dominate (for stars) in current models) ...
... (does work, but does not dominate (for stars) in current models) ...
The Universe - staff.harrisonburg.k12.va
... the earth outside our atmosphere. • It provides us with many of the images we have of space. • It is an especially useful telescope because it does not have to view things through our atmosphere ...
... the earth outside our atmosphere. • It provides us with many of the images we have of space. • It is an especially useful telescope because it does not have to view things through our atmosphere ...
The Universe
... the earth outside our atmosphere. • It provides us with many of the images we have of space. • It is an especially useful telescope because it does not have to view things through our atmosphere ...
... the earth outside our atmosphere. • It provides us with many of the images we have of space. • It is an especially useful telescope because it does not have to view things through our atmosphere ...
Ivelina Sotirova Major: Biochemistry Senior at CUNY Hunter College
... [1]. The validity of supernovae as a reliable marker throughout the deep space was officially confirmed by later research, and soon they were accepted as the perfect cosmos mapping tool [1]. Thus, the idea that the expansion of the Universe could be measured by using supernovae as standard candles w ...
... [1]. The validity of supernovae as a reliable marker throughout the deep space was officially confirmed by later research, and soon they were accepted as the perfect cosmos mapping tool [1]. Thus, the idea that the expansion of the Universe could be measured by using supernovae as standard candles w ...
Cosmology
... Cosmic Light Horizon •We cannot see objects whose distance is beyond 13.7 lightyears because light from these objects has not had enough time to reach us •Cosmic light horizon is the surface of the sphere with a radius of 13.7 light-years •It defines the size of the observable universe, even the un ...
... Cosmic Light Horizon •We cannot see objects whose distance is beyond 13.7 lightyears because light from these objects has not had enough time to reach us •Cosmic light horizon is the surface of the sphere with a radius of 13.7 light-years •It defines the size of the observable universe, even the un ...
Introduction - WordPress.com
... study of the Universe beyond Earth Astronomy is a true science. It includes the topics of the history of astronomy, human space exploration, our Sun and Moon, planets, other stars, galaxies, and cosmology (the origin, structure, and fate of the whole Universe). ...
... study of the Universe beyond Earth Astronomy is a true science. It includes the topics of the history of astronomy, human space exploration, our Sun and Moon, planets, other stars, galaxies, and cosmology (the origin, structure, and fate of the whole Universe). ...
Introduction - MSD of Martinsville
... study of the Universe beyond Earth Astronomy is a true science. It includes the topics of the history of astronomy, human space exploration, our Sun and Moon, planets, other stars, galaxies, and cosmology (the origin, structure, and fate of the whole Universe). ...
... study of the Universe beyond Earth Astronomy is a true science. It includes the topics of the history of astronomy, human space exploration, our Sun and Moon, planets, other stars, galaxies, and cosmology (the origin, structure, and fate of the whole Universe). ...
Slide 1
... 100,000 light years Millions of light years 10s of million light years 100 million light years ...
... 100,000 light years Millions of light years 10s of million light years 100 million light years ...
Chapter 12 - Our Place in the Universe
... that parallax can be used for nearby stars but then becomes difficult that Standard Candles have been identified (Type II supernova and Cepheids) that allow us to find the distance to far off stars and distant galaxies Starter: Recall units of measurement (put them in order of size) and radar rangi ...
... that parallax can be used for nearby stars but then becomes difficult that Standard Candles have been identified (Type II supernova and Cepheids) that allow us to find the distance to far off stars and distant galaxies Starter: Recall units of measurement (put them in order of size) and radar rangi ...
Foundations of Astronomy Presentation
... States that the Universe is a perfect sphere with Earth at the Center. Objects in space also move in perfect circles. ...
... States that the Universe is a perfect sphere with Earth at the Center. Objects in space also move in perfect circles. ...
Geocentric vs. Heliocentric
... States that the Universe is a perfect sphere with Earth at the Center. Objects in space also move in perfect circles. ...
... States that the Universe is a perfect sphere with Earth at the Center. Objects in space also move in perfect circles. ...
A Brief History of History
... A star is a ball of super-hot gas balanced between the twin tendencies to collapse under its own gravity, and the outward pressure of radiation energy. The balance is maintained as long as energy is being produced inside the star. Stars generate energy from nuclear reactions. In their cores the nucl ...
... A star is a ball of super-hot gas balanced between the twin tendencies to collapse under its own gravity, and the outward pressure of radiation energy. The balance is maintained as long as energy is being produced inside the star. Stars generate energy from nuclear reactions. In their cores the nucl ...
Shape of the universe
The shape of the universe is the local and global geometry of the Universe, in terms of both curvature and topology (though, strictly speaking, the concept goes beyond both). The shape of the universe is related to general relativity which describes how spacetime is curved and bent by mass and energy.There is a distinction between the observable universe and the global universe. The observable universe consists of the part of the universe that can, in principle, be observed due to the finite speed of light and the age of the universe. The observable universe is understood as a sphere around the Earth extending 93 billion light years (8.8 *1026 meters) and would be similar at any observing point (assuming the universe is indeed isotropic, as it appears to be from our vantage point).According to the book Our Mathematical Universe, the shape of the global universe can be explained with three categories: Finite or infinite Flat (no curvature), open (negative curvature) or closed (positive curvature) Connectivity, how the universe is put together, i.e., simply connected space or multiply connected.There are certain logical connections among these properties. For example, a universe with positive curvature is necessarily finite. Although it is usually assumed in the literature that a flat or negatively curved universe is infinite, this need not be the case if the topology is not the trivial one.The exact shape is still a matter of debate in physical cosmology, but experimental data from various, independent sources (WMAP, BOOMERanG and Planck for example) confirm that the observable universe is flat with only a 0.4% margin of error. Theorists have been trying to construct a formal mathematical model of the shape of the universe. In formal terms, this is a 3-manifold model corresponding to the spatial section (in comoving coordinates) of the 4-dimensional space-time of the universe. The model most theorists currently use is the so-called Friedmann–Lemaître–Robertson–Walker (FLRW) model. Arguments have been put forward that the observational data best fit with the conclusion that the shape of the global universe is infinite and flat, but the data are also consistent with other possible shapes, such as the so-called Poincaré dodecahedral space and the Picard horn.