Friday03
... density on 1.1 and 5.5 Mpc scales • groups are wellseparated in this plane, by velocity dispersion ...
... density on 1.1 and 5.5 Mpc scales • groups are wellseparated in this plane, by velocity dispersion ...
absolute brightness: The apparent brightness a star would have if it
... tiny pixels, each of which records a buildup of charge to measure the number of photons striking it. closed universe: Geometry that the universe as a whole would have if the density of matter is above the critical value. A closed universe is finite in extent, and has no edge, like the surface of a s ...
... tiny pixels, each of which records a buildup of charge to measure the number of photons striking it. closed universe: Geometry that the universe as a whole would have if the density of matter is above the critical value. A closed universe is finite in extent, and has no edge, like the surface of a s ...
absolute brightness: The apparent brightness a star would have if it
... tiny pixels, each of which records a buildup of charge to measure the number of photons striking it. closed universe: Geometry that the universe as a whole would have if the density of matter is above the critical value. A closed universe is finite in extent, and has no edge, like the surface of a s ...
... tiny pixels, each of which records a buildup of charge to measure the number of photons striking it. closed universe: Geometry that the universe as a whole would have if the density of matter is above the critical value. A closed universe is finite in extent, and has no edge, like the surface of a s ...
After School Guide to Ology Astronomy
... resources in the order provided within each unit is recommended, but you can also mix and match resources to create your own paths through the site. You will find two levels of skill question. (See “Skills” in the Using OLogy: Methods and Suggestions section of the Guide for a complete listing of th ...
... resources in the order provided within each unit is recommended, but you can also mix and match resources to create your own paths through the site. You will find two levels of skill question. (See “Skills” in the Using OLogy: Methods and Suggestions section of the Guide for a complete listing of th ...
Measuring Astronomical Distances
... allowed the telescope to observe a wider field of view This blind survey will get spectra for ~0.3 million galaxies in the SHELA field ...
... allowed the telescope to observe a wider field of view This blind survey will get spectra for ~0.3 million galaxies in the SHELA field ...
File
... In the 1920s, Edwin Hubble's discovery of a pattern in the red shift of light from galaxies moving away from Earth led to the theory of an expanding universe. This expansion implies that the universe was smaller, denser, and hotter in the past. In the 1940s, scientists predicted that heat (identifie ...
... In the 1920s, Edwin Hubble's discovery of a pattern in the red shift of light from galaxies moving away from Earth led to the theory of an expanding universe. This expansion implies that the universe was smaller, denser, and hotter in the past. In the 1940s, scientists predicted that heat (identifie ...
The kinematics of Galaxies in Compact Groups
... Rotation curves obtained from 2d velocity fields. DATA: Velocity fields for 29 galaxies Four were too peculiar for TF We used Vmax instead of Vflat (to be able to use more gal.) Control samples: Courteau (1997) and Verheijen (2001) Comparisons with previous studies: The 2D velocity maps obtained w ...
... Rotation curves obtained from 2d velocity fields. DATA: Velocity fields for 29 galaxies Four were too peculiar for TF We used Vmax instead of Vflat (to be able to use more gal.) Control samples: Courteau (1997) and Verheijen (2001) Comparisons with previous studies: The 2D velocity maps obtained w ...
Lecture1-1
... The actual measured data (left) and constructed models (model) are compared on the Dn(4000), HdA index plane. The solid lines in the left panels are tracks of burst star formation model and the points are “continuus” star formation model. ...
... The actual measured data (left) and constructed models (model) are compared on the Dn(4000), HdA index plane. The solid lines in the left panels are tracks of burst star formation model and the points are “continuus” star formation model. ...
OCR Physics A Refer to the Physics A datasheet for data, formulae
... © Oxford University Press 2016 http://www.oxfordsecondary.co.uk/acknowledgements This resource sheet may have been changed from the original ...
... © Oxford University Press 2016 http://www.oxfordsecondary.co.uk/acknowledgements This resource sheet may have been changed from the original ...
dark matter. - Gordon State College
... farther from the center. – This is not the case! – Objects in galaxies orbit at about the same speed no matter what their distance from the center of the galaxy. ...
... farther from the center. – This is not the case! – Objects in galaxies orbit at about the same speed no matter what their distance from the center of the galaxy. ...
Galaxies - University of Iowa Astrophysics
... - Each dot represents a galaxy. - The map extends out to nearly 3 billion light-years from Earth. - The galaxies lie on sheets, the largest structures known in the universe. - There are enormous voids where few galaxies are found. - On scales much larger than 100 Mpc, the distribution of galaxies ap ...
... - Each dot represents a galaxy. - The map extends out to nearly 3 billion light-years from Earth. - The galaxies lie on sheets, the largest structures known in the universe. - There are enormous voids where few galaxies are found. - On scales much larger than 100 Mpc, the distribution of galaxies ap ...
Andromeda Nebula Lies Outside Milky Way Galaxy
... studied many spiral nebulae. He has discovered they are moving away from us at a rapid pace. This is strong evidence of an expanding universe. He has further determined that the farther the nebula, the faster it moves away. Hubble and colleague Milton Humason measured the speeds and distances for tw ...
... studied many spiral nebulae. He has discovered they are moving away from us at a rapid pace. This is strong evidence of an expanding universe. He has further determined that the farther the nebula, the faster it moves away. Hubble and colleague Milton Humason measured the speeds and distances for tw ...
The Dance of the Fertile Universe
... understand the heavens; it was to know when to sow, when to reap, when the rainy season was coming, and all such things, so that they could live better on the surface of the earth. Well, where were their gods? Their gods were in those very heavens they were observing. For instance in the constellati ...
... understand the heavens; it was to know when to sow, when to reap, when the rainy season was coming, and all such things, so that they could live better on the surface of the earth. Well, where were their gods? Their gods were in those very heavens they were observing. For instance in the constellati ...
Teaching astrophysics in VCE Physics
... $ So we deduce that large stars die young, becoming giants or supergiants for a relatively short time, and then moving downward to become dwarfs as they collapse to electron degenerate matter. As they cool they eventually slide off to the lower right of the diagram. $ But some very large stars end t ...
... $ So we deduce that large stars die young, becoming giants or supergiants for a relatively short time, and then moving downward to become dwarfs as they collapse to electron degenerate matter. As they cool they eventually slide off to the lower right of the diagram. $ But some very large stars end t ...
PH607lec12
... census consist almost exclusively of very old stars, with much of their stellar populations having formed as long ago as 13 billion years. There appears to be very little recent star formation in these galaxies, nor is there strong evidence for recent ingestion of smaller, younger galaxies. By contr ...
... census consist almost exclusively of very old stars, with much of their stellar populations having formed as long ago as 13 billion years. There appears to be very little recent star formation in these galaxies, nor is there strong evidence for recent ingestion of smaller, younger galaxies. By contr ...
Spectroscopic confirmation of a galaxy at redshift z=8.6
... Figure 1 | Two representations of the spectrum of UDFy-38135539 showing its significance. a, The spectrum shows a faint emission line detected at 6s significance at a wavelength of 11,615.6 Å, corresponding to a redshift of z 5 8.5549 6 0.0020 for Lya. The integrated spectrum was extracted from a s ...
... Figure 1 | Two representations of the spectrum of UDFy-38135539 showing its significance. a, The spectrum shows a faint emission line detected at 6s significance at a wavelength of 11,615.6 Å, corresponding to a redshift of z 5 8.5549 6 0.0020 for Lya. The integrated spectrum was extracted from a s ...
5-E Galaxy T - McDonald Observatory
... Galaxies, compared to their size, are closer together than stars. They are also much more massive, having the combined mass of billions of stars. So, even over a large distance the force of gravity between galaxies can accelerate them toward each other. Think of bowling balls (galaxies) on a trampol ...
... Galaxies, compared to their size, are closer together than stars. They are also much more massive, having the combined mass of billions of stars. So, even over a large distance the force of gravity between galaxies can accelerate them toward each other. Think of bowling balls (galaxies) on a trampol ...
Planets and Moons - Fraser Heights Chess Club
... and billions of stars held together by gravity. One galaxy can have hundreds of billions of stars and be as large as 200,000 light years across. • Galaxy is derived from the Greek galaxias meaning "milky", a reference to the Milky Way. • Many galaxies are believed to have black holes at their active ...
... and billions of stars held together by gravity. One galaxy can have hundreds of billions of stars and be as large as 200,000 light years across. • Galaxy is derived from the Greek galaxias meaning "milky", a reference to the Milky Way. • Many galaxies are believed to have black holes at their active ...
Lecture-25 Notes - Georgia Southern University Astrophysics
... 4) “Regular” galaxy clusters are ~spherical, centrally concentrated, very massive, and are dominated by large ellipticals/S0’s in their cores. Spirals are found in the outskirts. Large amounts of ~107 K X-ray emitting gas is present. 5) “Irregular” clusters are smaller, looser, and dominated by spir ...
... 4) “Regular” galaxy clusters are ~spherical, centrally concentrated, very massive, and are dominated by large ellipticals/S0’s in their cores. Spirals are found in the outskirts. Large amounts of ~107 K X-ray emitting gas is present. 5) “Irregular” clusters are smaller, looser, and dominated by spir ...
Document
... that the universe experienced a significant decrease (factor ∼10) in the rate at which new stars were created. Star formation was much more rapid in the past, reaching a gentle peak at z ∼ 2 − 4 and falling off towards higher redshifts. Again, a number of physical processes may contribute to this de ...
... that the universe experienced a significant decrease (factor ∼10) in the rate at which new stars were created. Star formation was much more rapid in the past, reaching a gentle peak at z ∼ 2 − 4 and falling off towards higher redshifts. Again, a number of physical processes may contribute to this de ...
Galaxy Notes File
... This image shows the spiral galaxy NGC 4319 and the quasar Markarian 205. The distance to NGC is 80 million light years, which Mkn 205 is 14 times farther away at a distance of 1 billion light year. The very distant quasar is nearly as bright as the much closer galaxy. The extraordinary brightness o ...
... This image shows the spiral galaxy NGC 4319 and the quasar Markarian 205. The distance to NGC is 80 million light years, which Mkn 205 is 14 times farther away at a distance of 1 billion light year. The very distant quasar is nearly as bright as the much closer galaxy. The extraordinary brightness o ...
Galaxies - Stockton University
... – Black-holes are also efficient although less so than neutron stars • This is because black-holes have no surface so much of the energy is never released but is swallowed up by the black-hole directly and also orbits are unstable within three times the Schwarschild radius and little energy is retur ...
... – Black-holes are also efficient although less so than neutron stars • This is because black-holes have no surface so much of the energy is never released but is swallowed up by the black-hole directly and also orbits are unstable within three times the Schwarschild radius and little energy is retur ...
presentation (PPT format)
... • How did astronomers first discover other galaxies? • How did astronomers first determine the distances to galaxies? • Do all galaxies have spiral arms, like the Milky Way? • How do modern astronomers tell how far away galaxies are? • How do the spectra of galaxies tell astronomers that the univers ...
... • How did astronomers first discover other galaxies? • How did astronomers first determine the distances to galaxies? • Do all galaxies have spiral arms, like the Milky Way? • How do modern astronomers tell how far away galaxies are? • How do the spectra of galaxies tell astronomers that the univers ...
Observable universe
The observable universe consists of the galaxies and other matter that can, in principle, be observed from Earth at the present time because light and other signals from these objects has had time to reach the Earth since the beginning of the cosmological expansion. Assuming the universe is isotropic, the distance to the edge of the observable universe is roughly the same in every direction. That is, the observable universe is a spherical volume (a ball) centered on the observer. Every location in the Universe has its own observable universe, which may or may not overlap with the one centered on Earth.The word observable used in this sense does not depend on whether modern technology actually permits detection of radiation from an object in this region (or indeed on whether there is any radiation to detect). It simply indicates that it is possible in principle for light or other signals from the object to reach an observer on Earth. In practice, we can see light only from as far back as the time of photon decoupling in the recombination epoch. That is when particles were first able to emit photons that were not quickly re-absorbed by other particles. Before then, the Universe was filled with a plasma that was opaque to photons.The surface of last scattering is the collection of points in space at the exact distance that photons from the time of photon decoupling just reach us today. These are the photons we detect today as cosmic microwave background radiation (CMBR). However, with future technology, it may be possible to observe the still older relic neutrino background, or even more distant events via gravitational waves (which also should move at the speed of light). Sometimes astrophysicists distinguish between the visible universe, which includes only signals emitted since recombination—and the observable universe, which includes signals since the beginning of the cosmological expansion (the Big Bang in traditional cosmology, the end of the inflationary epoch in modern cosmology). According to calculations, the comoving distance (current proper distance) to particles from the CMBR, which represent the radius of the visible universe, is about 14.0 billion parsecs (about 45.7 billion light years), while the comoving distance to the edge of the observable universe is about 14.3 billion parsecs (about 46.6 billion light years), about 2% larger.The best estimate of the age of the universe as of 2015 is 7010137990000000000♠13.799±0.021 billion years but due to the expansion of space humans are observing objects that were originally much closer but are now considerably farther away (as defined in terms of cosmological proper distance, which is equal to the comoving distance at the present time) than a static 13.8 billion light-years distance. It is estimated that the diameter of the observable universe is about 28 gigaparsecs (91 billion light-years, 8.8×1026 metres or 5.5×1023 miles), putting the edge of the observable universe at about 46–47 billion light-years away.