Results from the search for tidal disruption flares in the GALEX Deep
... emission requires excitation by a persistent Seyfert nucleus. ...
... emission requires excitation by a persistent Seyfert nucleus. ...
Understanding the Astrophysics of Galaxy Evolution: the role of
... correlated with dark matter halo mass and so the best link to the underlying cosmological model. A survey must be large (∼ few ×105 galaxies) in order to disentangle covariances in the physical properties of galaxies. One reason it is so difficult to understand how galaxies form is because almost al ...
... correlated with dark matter halo mass and so the best link to the underlying cosmological model. A survey must be large (∼ few ×105 galaxies) in order to disentangle covariances in the physical properties of galaxies. One reason it is so difficult to understand how galaxies form is because almost al ...
Galaxies - University of Iowa Astrophysics
... A) They all have the same distance. B) Their luminosity can be determined from their pulsation period. C) They all have the same luminosity. D) They all have the same radius. ...
... A) They all have the same distance. B) Their luminosity can be determined from their pulsation period. C) They all have the same luminosity. D) They all have the same radius. ...
Extragalactic Distances from Planetary Nebulae
... Until recently, the sample of galaxies with well-observed Type Ia supernovae and PNLF measurements was too small to be useful. This is now changing. ...
... Until recently, the sample of galaxies with well-observed Type Ia supernovae and PNLF measurements was too small to be useful. This is now changing. ...
normal and active - FirstLight Astro
... remember stars are stinking far apart, but galaxies are relatively VERY close to each other so they inevitably collide, although their stars almost never collide, their gas & dust do… ...
... remember stars are stinking far apart, but galaxies are relatively VERY close to each other so they inevitably collide, although their stars almost never collide, their gas & dust do… ...
19_Testbank - Lick Observatory
... C) in the Big Bang, when the universe first began D) none of the above E) all of the above Answer: B 14) Why are we unlikely to find Earth-like planets around halo stars in the Galaxy? A) Planets around stars are known to be extremely rare. B) Halo stars formed in an environment where there were few ...
... C) in the Big Bang, when the universe first began D) none of the above E) all of the above Answer: B 14) Why are we unlikely to find Earth-like planets around halo stars in the Galaxy? A) Planets around stars are known to be extremely rare. B) Halo stars formed in an environment where there were few ...
Disk Galaxies in the Magneticum Pathfinder Simulations
... procedure similar to Scannapieco et al. (2008): we align each galaxy along its principal axis of inertia of the stars within 0.1Rvir and subsequently classify it according to the circularity parameter ǫ = jz /jcirc , where jz is the specific angular momentum of each particle with respect to the z-ax ...
... procedure similar to Scannapieco et al. (2008): we align each galaxy along its principal axis of inertia of the stars within 0.1Rvir and subsequently classify it according to the circularity parameter ǫ = jz /jcirc , where jz is the specific angular momentum of each particle with respect to the z-ax ...
The Hubble Law - Department of Astronomy
... There are a couple of features you should especially note when trying to decipher these spectra: 1. Not all of the "jiggly" lines come from the light of the galaxy. Each spectrum contains noise; we just cannot get away from it. You should notice that some of the spectra are much "noisier" than othe ...
... There are a couple of features you should especially note when trying to decipher these spectra: 1. Not all of the "jiggly" lines come from the light of the galaxy. Each spectrum contains noise; we just cannot get away from it. You should notice that some of the spectra are much "noisier" than othe ...
Baryons at Low Densities: The Stellar Halos around Galaxies
... clusters) survey. The high angular resolution of the Hubble Space Telescope (HST) allows the detection of single stars in halos at larger distances and in denser regions — hence investigating the transition regions between the disc and halo. All MW-like galaxies observed by GHOSTS have extended stel ...
... clusters) survey. The high angular resolution of the Hubble Space Telescope (HST) allows the detection of single stars in halos at larger distances and in denser regions — hence investigating the transition regions between the disc and halo. All MW-like galaxies observed by GHOSTS have extended stel ...
The Formation and Evolution of the Milky Way
... such as the Sun, have a small vertical velocity and tend to stay in the galactic plane, whereas thick-disk stars have slightly larger vertical velocities, and halo stars tend to have the largest vertical velocities (and almost no rotational velocity). A star’s kinematic properties are one of the way ...
... such as the Sun, have a small vertical velocity and tend to stay in the galactic plane, whereas thick-disk stars have slightly larger vertical velocities, and halo stars tend to have the largest vertical velocities (and almost no rotational velocity). A star’s kinematic properties are one of the way ...
Cepheid Stars as standard candles for distance measurements
... similar stars as variable resulted from brightness measurements. Approximately 200 years later, Pigott and Goodricke found two other stars with a brightness variation. In 1784, Goodricke could detect a period of 5d 8h 47min for δ Cephei’s change in brightness. Since δ Cephei was the first variable s ...
... similar stars as variable resulted from brightness measurements. Approximately 200 years later, Pigott and Goodricke found two other stars with a brightness variation. In 1784, Goodricke could detect a period of 5d 8h 47min for δ Cephei’s change in brightness. Since δ Cephei was the first variable s ...
LET`S MAKE A PORTRAIT OF A GALAXY Abstract
... distribution of stars referred to as the nucleus. The nucleus of the spiral galaxy and the halo of globular clusters surrounding the galaxy contain mostly old stars - called Population II type stars. The spiral arms contain a mixture of old and new stars Population I type stars. There is also gas an ...
... distribution of stars referred to as the nucleus. The nucleus of the spiral galaxy and the halo of globular clusters surrounding the galaxy contain mostly old stars - called Population II type stars. The spiral arms contain a mixture of old and new stars Population I type stars. There is also gas an ...
Galaxy Sorting
... featureless spherical or ellipsoidal (footballshaped) collections of stars; 2) spiral galaxies, with their distinctive arms of stars that spiral out from their centers; and 3) irregular galaxies, a catch all category for galaxies that don't look like either traditional ellipticals or spirals. E ...
... featureless spherical or ellipsoidal (footballshaped) collections of stars; 2) spiral galaxies, with their distinctive arms of stars that spiral out from their centers; and 3) irregular galaxies, a catch all category for galaxies that don't look like either traditional ellipticals or spirals. E ...
Lecture-25 Notes - Georgia Southern University Astrophysics
... These massive galaxies (and their super-massive black holes) had formed before the universe was 1-billion years old!! A z = 7.1 QSO has recently been discovered. It formed ~300-million years after the creation of the universe!! ...
... These massive galaxies (and their super-massive black holes) had formed before the universe was 1-billion years old!! A z = 7.1 QSO has recently been discovered. It formed ~300-million years after the creation of the universe!! ...
Andromeda Galaxy
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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.