![The Relative Ages of M5 and Pal 4/Eridanus from their](http://s1.studyres.com/store/data/008077860_1-1d27f9c3fc6834a1a8fa3c05aed4fdef-300x300.png)
The Relative Ages of M5 and Pal 4/Eridanus from their
... of 2 smaller than their rotation velocity. This implies that the LMC is kinematically cold, and must therefore be a disk system. ...
... of 2 smaller than their rotation velocity. This implies that the LMC is kinematically cold, and must therefore be a disk system. ...
The 100-billion-body problem A full-scale computer simulation of the
... The number of time steps can also present a computational challenge. Each step should be brief enough that the distance between pairs of stars does not change by more than a few percent. For stars that are many lightyears apart, time steps of several thousand years give acceptable results, but close ...
... The number of time steps can also present a computational challenge. Each step should be brief enough that the distance between pairs of stars does not change by more than a few percent. For stars that are many lightyears apart, time steps of several thousand years give acceptable results, but close ...
Detecting Habitable Planets around Nearby Sun-Like Stars
... angle of sky in the direction of Cygnus/Lyra. – Stars at average distance of ~1 kpc. • Difficult to follow up by direct detection. ...
... angle of sky in the direction of Cygnus/Lyra. – Stars at average distance of ~1 kpc. • Difficult to follow up by direct detection. ...
Planet Characterization by Transit Observations
... • observed absorption levels are weaker than cloudless models ...
... • observed absorption levels are weaker than cloudless models ...
New Astrophysical Opportunities Exploiting Spatio-Temporal Optical Correlations
... nuclear activity. The VLTI has succeeded in resolving structures in the AGN torus at midinfrared wavelengths [23] on scales of 30 milli-arcsecond. On the other hand, the blue optical continuum emission is dominated by thermal emission from the inner accretion disk (the source of the “big blue bump” ...
... nuclear activity. The VLTI has succeeded in resolving structures in the AGN torus at midinfrared wavelengths [23] on scales of 30 milli-arcsecond. On the other hand, the blue optical continuum emission is dominated by thermal emission from the inner accretion disk (the source of the “big blue bump” ...
a thermonuclear flame has almost completed TEN SECONDS AFTER IGNITION,
... Like a crystal vase falling onto a concrete floor, the collapsing material releases enough gravitational potential energy to blow the rest of the star apart. An alternative emerged in 1960, when Fred Hoyle of the University of Cambridge and Willy Fowler of Caltech conceived of the explosions as giant ...
... Like a crystal vase falling onto a concrete floor, the collapsing material releases enough gravitational potential energy to blow the rest of the star apart. An alternative emerged in 1960, when Fred Hoyle of the University of Cambridge and Willy Fowler of Caltech conceived of the explosions as giant ...
... • At a distance of 3 kpc, an arc of cold hydrogen sweeps outward at a speed exceeding 100 km/sec • A giant swarm of stars, packed in at millions of stars per cubic light-year, are arranged in an elongated structure about 1000 light-years across • Some energetic event, perhaps a supernova explosion, ...
Spots on Ap Stars
... • Electrons accelerate down the magnetic field lines toward the lower atmosphere, producing microwave emission • Electrons collide with ions, producing hard x-rays, white light emission from chromosphere • Chromospheric plasma heated to coronal temperatures, hot plasma flows up into the corona • Sho ...
... • Electrons accelerate down the magnetic field lines toward the lower atmosphere, producing microwave emission • Electrons collide with ions, producing hard x-rays, white light emission from chromosphere • Chromospheric plasma heated to coronal temperatures, hot plasma flows up into the corona • Sho ...
Spectroscopic Studies of Evolved Stars and Planetary Nebulae
... formation. These objects undergo dramatic mass loss which ultimately enriches the interstellar medium. In this thesis, a number of studies, outlined below, have been undertaken to better understand the chemical and physical properties of these diverse objects. A molecular line survey of a sample of ...
... formation. These objects undergo dramatic mass loss which ultimately enriches the interstellar medium. In this thesis, a number of studies, outlined below, have been undertaken to better understand the chemical and physical properties of these diverse objects. A molecular line survey of a sample of ...
Powerpoint
... approach the Eddington luminosity with L proportional to M. In fact, except for a thin region near their surfaces, such stars will be entirely convective and will have a total binding energy that approaches zero as approaches zero. But the calculation applies to those surface layers which must sta ...
... approach the Eddington luminosity with L proportional to M. In fact, except for a thin region near their surfaces, such stars will be entirely convective and will have a total binding energy that approaches zero as approaches zero. But the calculation applies to those surface layers which must sta ...
Kinematics of the Solar Neighborhood
... We do not presently know very much about the orientation of the velocity ellipsoid away from the midplane. If the ellipsoid remains parallel for all z values then this term is identically zero, while if the ellipsoid tilts to always point at the galactic center then ...
... We do not presently know very much about the orientation of the velocity ellipsoid away from the midplane. If the ellipsoid remains parallel for all z values then this term is identically zero, while if the ellipsoid tilts to always point at the galactic center then ...
Discovery of WASP-65b and WASP-75b: Two Hot Jupiters Without
... heating (Batygin & Stevenson 2010; Wu & Lithwick 2012) have been proposed to explain these anomalously large radii (see also Baraffe et al. 2010). However, a single mechanism has not been able to explain the entire range of observed radii, and it is possible that a combination of them come into play ...
... heating (Batygin & Stevenson 2010; Wu & Lithwick 2012) have been proposed to explain these anomalously large radii (see also Baraffe et al. 2010). However, a single mechanism has not been able to explain the entire range of observed radii, and it is possible that a combination of them come into play ...
Chapter 15
... • At a distance of 3 kpc, an arc of cold hydrogen sweeps outward at a speed exceeding 100 km/sec • A giant swarm of stars, packed in at millions of stars per cubic light-year, are arranged in an elongated structure about 1000 light-years across • Some energetic event, perhaps a supernova explosion, ...
... • At a distance of 3 kpc, an arc of cold hydrogen sweeps outward at a speed exceeding 100 km/sec • A giant swarm of stars, packed in at millions of stars per cubic light-year, are arranged in an elongated structure about 1000 light-years across • Some energetic event, perhaps a supernova explosion, ...
Basics of chemical evolution
... Chemical evolution • The metal abundance of the gas, and of subsequent generations of stars, should increase in time. – if there is no gas infall from the outside ...
... Chemical evolution • The metal abundance of the gas, and of subsequent generations of stars, should increase in time. – if there is no gas infall from the outside ...
4. Star Formation
... It is now well established that stars form from gas and dust in the ISM. Young stars and massive stars are preferably found close to/within molecular clouds. This obscuration hence requires observations at infrared, millimetre, or radio wavelength. The problems of star formation: Create a star (radi ...
... It is now well established that stars form from gas and dust in the ISM. Young stars and massive stars are preferably found close to/within molecular clouds. This obscuration hence requires observations at infrared, millimetre, or radio wavelength. The problems of star formation: Create a star (radi ...
PH607lec07
... outer rim, the typical stellar velocity is between 210 and 240 km/s. Hence the orbital period of the typical star is directly proportional only to the length of the path travelled. This is unlike the solar system where different orbits are also expected to have significantly different velocities ass ...
... outer rim, the typical stellar velocity is between 210 and 240 km/s. Hence the orbital period of the typical star is directly proportional only to the length of the path travelled. This is unlike the solar system where different orbits are also expected to have significantly different velocities ass ...
Layers of the Sun Test 1 study guide. Intoduction to Stars
... Radiation Layer • temperature 100,000 to 5,000,000 degrees (plasma) • no fusion • electrons are not in atoms very, very opaque • Energy transferred by absorption and reradiation of light ...
... Radiation Layer • temperature 100,000 to 5,000,000 degrees (plasma) • no fusion • electrons are not in atoms very, very opaque • Energy transferred by absorption and reradiation of light ...
Time From the Perspective of a Particle Physicist
... Radiation Layer • temperature 100,000 to 5,000,000 degrees (plasma) • no fusion • electrons are not in atoms very, very opaque • Energy transferred by absorption and reradiation of light ...
... Radiation Layer • temperature 100,000 to 5,000,000 degrees (plasma) • no fusion • electrons are not in atoms very, very opaque • Energy transferred by absorption and reradiation of light ...
3919 - newmanlib.ibri.org
... kkb, Akk. kakkabu, Aram. kôkb', Syr. kaukeb, Arab. kaukab. Etymologies have been proposed from kbb, burn (Akk., Aram. and Arab.) and from kabba, roll, revolve (Arab.). Unlike modern Eng. usage but parallel to ancient G, the Sem. word probably includes planets, comets, meteors, or any bright object ...
... kkb, Akk. kakkabu, Aram. kôkb', Syr. kaukeb, Arab. kaukab. Etymologies have been proposed from kbb, burn (Akk., Aram. and Arab.) and from kabba, roll, revolve (Arab.). Unlike modern Eng. usage but parallel to ancient G, the Sem. word probably includes planets, comets, meteors, or any bright object ...
Astronomy Exam #2 for the 10
... These brightest stars are all (almost) all more O B A F G K M luminous than the Sun, shorter lived than the Sun, Spectral Type and are either hotter main sequence stars or cooler giant stars (mostly). These brightest stars are a hundreds of times more luminous if not more and will therefore have lif ...
... These brightest stars are all (almost) all more O B A F G K M luminous than the Sun, shorter lived than the Sun, Spectral Type and are either hotter main sequence stars or cooler giant stars (mostly). These brightest stars are a hundreds of times more luminous if not more and will therefore have lif ...
Astronomy 535 Stellar Structure Evolution
... • Evolution of ISM, IGM, gas fraction, composition, star formation, populations, galaxies, baryonic matter in general profoundly depends on stellar evolution • Fits of models to observations by means of free parameters is standard procedure, but gives unreliable or downright bad results for most app ...
... • Evolution of ISM, IGM, gas fraction, composition, star formation, populations, galaxies, baryonic matter in general profoundly depends on stellar evolution • Fits of models to observations by means of free parameters is standard procedure, but gives unreliable or downright bad results for most app ...
42 SCIENTIFIC AMERICAN OCTOBER 2006 TEN
... reaches the density of an atomic nucleus. Like a crystal vase falling onto a concrete floor, the collapsing material releases enough gravitational potential energy to blow the rest of the star apart. An alternative emerged in 1960, when Fred Hoyle of the University of Cambridge and Willy Fowler of C ...
... reaches the density of an atomic nucleus. Like a crystal vase falling onto a concrete floor, the collapsing material releases enough gravitational potential energy to blow the rest of the star apart. An alternative emerged in 1960, when Fred Hoyle of the University of Cambridge and Willy Fowler of C ...
Astronomy Chapter 16 – The Milky Way Galaxy A. Main Ideas 1
... ⇒ Interstellar gas is the material from which stars form, and it is the repository (storage place) of matter blown off dying stars 5. Motion of Stars and Gas in the Milky Way Although all stars within the Milky Way move around its center, the paths followed by stars in the disk and halo are very dif ...
... ⇒ Interstellar gas is the material from which stars form, and it is the repository (storage place) of matter blown off dying stars 5. Motion of Stars and Gas in the Milky Way Although all stars within the Milky Way move around its center, the paths followed by stars in the disk and halo are very dif ...
PPT Slides - Center for Computational Sciences
... • Densities build up until fusion starts in the center. ...
... • Densities build up until fusion starts in the center. ...
Planetary nebula
![](https://commons.wikimedia.org/wiki/Special:FilePath/NGC6543.jpg?width=300)
A planetary nebula, often abbreviated as PN or plural PNe, is a kind of emission nebula consisting of an expanding glowing shell of ionized gas ejected from old red giant stars late in their lives. The word ""nebula"" is Latin for mist or cloud and the term ""planetary nebula"" is a misnomer that originated in the 1780s with astronomer William Herschel because when viewed through his telescope, these objects appeared to him to resemble the rounded shapes of planets. Herschel's name for these objects was popularly adopted and has not been changed. They are a relatively short-lived phenomenon, lasting a few tens of thousands of years, compared to a typical stellar lifetime of several billion years.A mechanism for formation of most planetary nebulae is thought to be the following: at the end of the star's life, during the red giant phase, the outer layers of the star are expelled by strong stellar winds. Eventually, after most of the red giant's atmosphere is dissipated, the exposed hot, luminous core emits ultraviolet radiation to ionize the ejected outer layers of the star. Absorbed ultraviolet light energises the shell of nebulous gas around the central star, appearing as a bright coloured planetary nebula at several discrete visible wavelengths.Planetary nebulae may play a crucial role in the chemical evolution of the Milky Way, returning material to the interstellar medium from stars where elements, the products of nucleosynthesis (such as carbon, nitrogen, oxygen and neon), have been created. Planetary nebulae are also observed in more distant galaxies, yielding useful information about their chemical abundances.In recent years, Hubble Space Telescope images have revealed many planetary nebulae to have extremely complex and varied morphologies. About one-fifth are roughly spherical, but the majority are not spherically symmetric. The mechanisms which produce such a wide variety of shapes and features are not yet well understood, but binary central stars, stellar winds and magnetic fields may play a role.