ASPEN WORKSHOP 2003
... Asymmetry index is another way to identify mergers (subtract flipped image), zero in ellipticals, larger in bluer galaxies, up to few tenths. AI(Red), or AI(Blue) >0.3 suggests interaction, as in half of ULIRGS [as long as they are identified as “single galaxy”!] Simulations show that AI stays above ...
... Asymmetry index is another way to identify mergers (subtract flipped image), zero in ellipticals, larger in bluer galaxies, up to few tenths. AI(Red), or AI(Blue) >0.3 suggests interaction, as in half of ULIRGS [as long as they are identified as “single galaxy”!] Simulations show that AI stays above ...
sections 23-25 powerpoint
... Elliptical galaxy (E). A spheroidal galaxy containing millions to billions of old low-mass stars and no gas or dust. Spiral Galaxy (S). A galaxy with a spheroidal bulge of several million old low-mass stars and a flattened pancake-like disk of billions of old low-mass and young high-mass stars, alon ...
... Elliptical galaxy (E). A spheroidal galaxy containing millions to billions of old low-mass stars and no gas or dust. Spiral Galaxy (S). A galaxy with a spheroidal bulge of several million old low-mass stars and a flattened pancake-like disk of billions of old low-mass and young high-mass stars, alon ...
ROTATION CURVES OF HIGH-LUMINOSITY SPIRAL GALAXIES
... The following conclusions come from analysis of these data (Rubin, Ford, and Thonnard 1978): (1) All rotation curves are nearly flat to distances as great as 50 kpc radius. Eight of these 11 galaxies have their maximum velocity at r > 10 k p c Secondary velocity undulations indicate that rotational ...
... The following conclusions come from analysis of these data (Rubin, Ford, and Thonnard 1978): (1) All rotation curves are nearly flat to distances as great as 50 kpc radius. Eight of these 11 galaxies have their maximum velocity at r > 10 k p c Secondary velocity undulations indicate that rotational ...
PH607lec09-3gal1
... • The surface brightnesses of E galaxies do not always decline smoothly with radius. When a smooth luminosity profile is subtracted from the actual surface brightness, `shells' or `ripples', centered on the galaxy, are seen. • The fraction of field E galaxies with shell-like features is at least 17% ...
... • The surface brightnesses of E galaxies do not always decline smoothly with radius. When a smooth luminosity profile is subtracted from the actual surface brightness, `shells' or `ripples', centered on the galaxy, are seen. • The fraction of field E galaxies with shell-like features is at least 17% ...
Lecture 8: Spiral Structure
... The self-propagating star formation theory • According to the self-propagating star formation theory of galactic spiral arms, the triggers that start the collapse of the interstellar clouds are nearby supernovae explosions. Then, as the more massive stars finish their lives and become supernovae, ...
... The self-propagating star formation theory • According to the self-propagating star formation theory of galactic spiral arms, the triggers that start the collapse of the interstellar clouds are nearby supernovae explosions. Then, as the more massive stars finish their lives and become supernovae, ...
WELCOME TO THE MILKY WAY
... place. When two galaxies merge, there is so much clear space that their stars never collide. We can describe the Milky Way as a huge rotating disk of smoothly distributed (mainly A, F and G) stars. The disk is about 3,000 ly thick and measures 100,000 ly in diameter. At the center of the disk, there ...
... place. When two galaxies merge, there is so much clear space that their stars never collide. We can describe the Milky Way as a huge rotating disk of smoothly distributed (mainly A, F and G) stars. The disk is about 3,000 ly thick and measures 100,000 ly in diameter. At the center of the disk, there ...
Course Outline - Tony Bacigalupo
... The region of a galaxy beyond the visible halo where dark matter is believed to reside Composition? ...
... The region of a galaxy beyond the visible halo where dark matter is believed to reside Composition? ...
A Zoo of Galaxies
... To say our understanding of the “zoo” of galaxies that are found in our Universe has changed a lot over the last century or two is a bit of an understatement. In 1845 the state of the art picture of an external galaxy, was an image of M51, or the Whirlpool galaxy drawn by William Parsons, Third Earl ...
... To say our understanding of the “zoo” of galaxies that are found in our Universe has changed a lot over the last century or two is a bit of an understatement. In 1845 the state of the art picture of an external galaxy, was an image of M51, or the Whirlpool galaxy drawn by William Parsons, Third Earl ...
What are Messier Objects? - Bowling Green State University
... cluster in Orion. Also known as the Orion Nebula. Is one of the brightest starforming nebulae and one of the brightest diffusion nebulae in the sky It is a big object, considered to cover four times the area of the full moon. Located 1,600 light years away. Is a very turbulent cloud of gas ...
... cluster in Orion. Also known as the Orion Nebula. Is one of the brightest starforming nebulae and one of the brightest diffusion nebulae in the sky It is a big object, considered to cover four times the area of the full moon. Located 1,600 light years away. Is a very turbulent cloud of gas ...
21_Testbank
... light but extraordinary when they are observed in infrared light. Answer: Starburst galaxies are filled with star-forming molecular clouds, which contain dust grains that absorb most of the visible light produced by the young stars. This radiation heats the dust grains to very high temperatures, and ...
... light but extraordinary when they are observed in infrared light. Answer: Starburst galaxies are filled with star-forming molecular clouds, which contain dust grains that absorb most of the visible light produced by the young stars. This radiation heats the dust grains to very high temperatures, and ...
The Diverse Galaxies
... Measuring distant objects more than 100 millions of light-years (100 Mly) requires an even more luminous object Sometime large galaxies can be used as standard candles The white dwarf supernovae is a very consistent since 1.4 solar masses (the Chandrasekar limit) is always exploding. ...
... Measuring distant objects more than 100 millions of light-years (100 Mly) requires an even more luminous object Sometime large galaxies can be used as standard candles The white dwarf supernovae is a very consistent since 1.4 solar masses (the Chandrasekar limit) is always exploding. ...
Galaxies - WordPress.com
... B the collisional merging of galaxies in an irregular cluster of galaxies C stars pulled from nearby galaxies in a cluster by a larger-than-normal elliptical galaxies D gas ripped from galaxies in compact clusters by tidal forces ...
... B the collisional merging of galaxies in an irregular cluster of galaxies C stars pulled from nearby galaxies in a cluster by a larger-than-normal elliptical galaxies D gas ripped from galaxies in compact clusters by tidal forces ...
Andromeda Galaxy
The Andromeda Galaxy (/ænˈdrɒmɨdə/), also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth. It is the nearest major galaxy to the Milky Way and was often referred to as the Great Andromeda Nebula in older texts. It received its name from the area of the sky in which it appears, the constellation of Andromeda, which was named after the mythological princess Andromeda. Being approximately 220,000 light years across, it is the largest galaxy of the Local Group, which also contains the Milky Way, the Triangulum Galaxy, and about 44 other smaller galaxies.The Andromeda Galaxy is the most massive galaxy in the Local Group as well. Despite earlier findings that suggested that the Milky Way contains more dark matter and could be the most massive in the grouping, the 2006 observations by the Spitzer Space Telescope revealed that Andromeda contains one trillion (1012) stars: at least twice the number of stars in the Milky Way, which is estimated to be 200–400 billion.The Andromeda Galaxy is estimated to be 1.5×1012 solar masses, while the mass of the Milky Way is estimated to be 8.5×1011 solar masses. In comparison, a 2009 study estimated that the Milky Way and M31 are about equal in mass, while a 2006 study put the mass of the Milky Way at ~80% of the mass of the Andromeda Galaxy. The Milky Way and Andromeda are expected to collide in 3.75 billion years, eventually merging to form a giant elliptical galaxy or perhaps a large disk galaxy.At 3.4, the apparent magnitude of the Andromeda Galaxy is one of the brightest of any of the Messier objects, making it visible to the naked eye on moonless nights even when viewed from areas with moderate light pollution. Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye or when viewed using binoculars or a small telescope and would it hence appear to be but another star.