here - Stars `r` Us!
... he title of this article needs some explanation. Clearly, the universe is not entirely made of molecules and we are exaggerating. In fact, most of the mass in the universe is probably not even made of familiar matter, i.e. the atoms and molecules of which we, the Earth, the solar system, and all the ...
... he title of this article needs some explanation. Clearly, the universe is not entirely made of molecules and we are exaggerating. In fact, most of the mass in the universe is probably not even made of familiar matter, i.e. the atoms and molecules of which we, the Earth, the solar system, and all the ...
Weighing Ultracompact Dwarf Galaxies in the Fornax Cluster
... 200 times more extended. It has been believed that dwarf galaxies are diffuse structures, with the exception of the compact elliptical M32, a companion of the Andromeda galaxy, which is ~ 8–10 times smaller than dwarf ellipticals of comparable luminosities, but about 150 times more luminous than the ...
... 200 times more extended. It has been believed that dwarf galaxies are diffuse structures, with the exception of the compact elliptical M32, a companion of the Andromeda galaxy, which is ~ 8–10 times smaller than dwarf ellipticals of comparable luminosities, but about 150 times more luminous than the ...
X-ray Emission Line Profile Diagnostics of Hot Star Winds
... depth), BUT the lines we fit cover only a modest range of wavelengths. And in the case of z Pup, nitrogen overabundance (not in calculation shown at right) could flatten out the wavelength dependence even more. ...
... depth), BUT the lines we fit cover only a modest range of wavelengths. And in the case of z Pup, nitrogen overabundance (not in calculation shown at right) could flatten out the wavelength dependence even more. ...
A new isolated dSph galaxy near the Local Group
... than a dozen dSphs were discovered by Chiboucas, Karachentsev & Tully (2009) in the nearby group around M81. The discoveries resulted from targeted searches within small parts of the sky (∼390 and ∼65 deg2 , respectively). The hunt for isolated spheroidal dwarfs is very difficult because it requires ...
... than a dozen dSphs were discovered by Chiboucas, Karachentsev & Tully (2009) in the nearby group around M81. The discoveries resulted from targeted searches within small parts of the sky (∼390 and ∼65 deg2 , respectively). The hunt for isolated spheroidal dwarfs is very difficult because it requires ...
Effects of color superconductivity on the nucleation of
... which gives rise to large critical masses. The converstion to a quark star will occur only for a small value of the bag constant. Both QMC and GM1 with the largest hyperon-meson couplings predict critical masses which may be as high as 1.9-2.1 M, compatible with the masses of the millisecond pulsar ...
... which gives rise to large critical masses. The converstion to a quark star will occur only for a small value of the bag constant. Both QMC and GM1 with the largest hyperon-meson couplings predict critical masses which may be as high as 1.9-2.1 M, compatible with the masses of the millisecond pulsar ...
Young Stellar Objects in the Orion B Cloud
... is 28 %, which, after a correction for contamination with field stars, is more like ~ 20 %. This, as well as the overall shape of the mass function, is remarkably similar to the Orion Trapezium KLF, which has been reported to have a fraction of substellar objects of ~ 22 % (Muench et al. 2002). We c ...
... is 28 %, which, after a correction for contamination with field stars, is more like ~ 20 %. This, as well as the overall shape of the mass function, is remarkably similar to the Orion Trapezium KLF, which has been reported to have a fraction of substellar objects of ~ 22 % (Muench et al. 2002). We c ...
Physical properties of the HAT-P-23 and WASP
... the physical properties of exoplanets. A good knowledge of the main characteristics of the exoplanets is fundamental in order to trace their origin and evolution. Multi-band photometric observations play an important role in this process. Aims. By using new photometric data, we computed precise esti ...
... the physical properties of exoplanets. A good knowledge of the main characteristics of the exoplanets is fundamental in order to trace their origin and evolution. Multi-band photometric observations play an important role in this process. Aims. By using new photometric data, we computed precise esti ...
Paul Green - Chandra X-Ray Observatory (CXC)
... Professor Philip Morrison of Cornell thinks the X rays may be generated when starlight picks up energy from high-speed electrons far out in space. Professor Minoru Oda of M.I.T. figures that the X rays come from a magnetic field surrounding the edges of the galactic nucleus. British Cosmologist Fred ...
... Professor Philip Morrison of Cornell thinks the X rays may be generated when starlight picks up energy from high-speed electrons far out in space. Professor Minoru Oda of M.I.T. figures that the X rays come from a magnetic field surrounding the edges of the galactic nucleus. British Cosmologist Fred ...
Models of red giants in the CoRoT asteroseismology fields
... Additionally and independent of spectroscopy, the core rotation rate of red giant stars measured by asteroseismology (e.g. Beck et al. 2012; Deheuvels et al. 2012, 2014) shows a significant disagreement with models predictions. It is clear that the physics of red giant models should be improved in t ...
... Additionally and independent of spectroscopy, the core rotation rate of red giant stars measured by asteroseismology (e.g. Beck et al. 2012; Deheuvels et al. 2012, 2014) shows a significant disagreement with models predictions. It is clear that the physics of red giant models should be improved in t ...
Summary of IAU GA SpS5-I. Obscured and distant clusters
... Way using recent, current and future surveys such as 2MASS, Spitzer, WISE, VISTA. They provide outstanding, homogenous large-scale data sets and are ideally suited for such searches. Unbiased, targeted and serendipitous methods have already been mentioned as a means for locating new young clusters. ...
... Way using recent, current and future surveys such as 2MASS, Spitzer, WISE, VISTA. They provide outstanding, homogenous large-scale data sets and are ideally suited for such searches. Unbiased, targeted and serendipitous methods have already been mentioned as a means for locating new young clusters. ...
Full text - terrapub
... have shown that the plasma tail of Mars consists mainly of ions of planetary origin (Lundin et al., 1989a, b; Rosenbauer et al., 1989). Lundin et al. (1989a, b, 1990) estimated that the planet is losing oxygen at a rate of about 3 × 1025 ions/ s. This value is sufficiently high to explain a dehydrat ...
... have shown that the plasma tail of Mars consists mainly of ions of planetary origin (Lundin et al., 1989a, b; Rosenbauer et al., 1989). Lundin et al. (1989a, b, 1990) estimated that the planet is losing oxygen at a rate of about 3 × 1025 ions/ s. This value is sufficiently high to explain a dehydrat ...
Orbital Orientations of Exoplanets: Hat-p-4b is Prograde and Hat
... where the first term is the usual sum of squared residuals, and the other terms enforce Gaussian priors. In this expression, Pdays is the orbital period in days, Tc is a particular time of inferior conjunction (in the HJDUTC system); Tdays is the time between first and fourth contact; τdays is the t ...
... where the first term is the usual sum of squared residuals, and the other terms enforce Gaussian priors. In this expression, Pdays is the orbital period in days, Tc is a particular time of inferior conjunction (in the HJDUTC system); Tdays is the time between first and fourth contact; τdays is the t ...
The AcroCoRoT objectives (10 min) - IAG-Usp
... What physical processes control the behavior of rotation during stellar evolution from PMS to PostMS Giants? How does magnetic breaking affect rotation ? What physical processes control the generation of magnetic field? What type(s) of dynamo is at play in stellar interiors? Do we correctly understa ...
... What physical processes control the behavior of rotation during stellar evolution from PMS to PostMS Giants? How does magnetic breaking affect rotation ? What physical processes control the generation of magnetic field? What type(s) of dynamo is at play in stellar interiors? Do we correctly understa ...
The origin of magnetism on the upper main sequence
... upper-main-sequence stars are deficient in close binary companions. A curious fact, first noted by Abt & Snowden (1973) in mid- and upper-main-sequence magnetic stars, is that they tend not to be members of close binary systems even though they do occur with the normal frequency in wide binary syste ...
... upper-main-sequence stars are deficient in close binary companions. A curious fact, first noted by Abt & Snowden (1973) in mid- and upper-main-sequence magnetic stars, is that they tend not to be members of close binary systems even though they do occur with the normal frequency in wide binary syste ...
The mid- and far-infrared range - International Space Science Institute
... of CO occur at shorter wavelengths than low-J transitions and hence they probe warmer and denser gas. Likewise, as a hydride, H2 transitions occur at much shorter wavelengths than those of the heavier molecule CO. However, as a homonuclear molecule, H2 has only quadrupole-allowed transitions with mu ...
... of CO occur at shorter wavelengths than low-J transitions and hence they probe warmer and denser gas. Likewise, as a hydride, H2 transitions occur at much shorter wavelengths than those of the heavier molecule CO. However, as a homonuclear molecule, H2 has only quadrupole-allowed transitions with mu ...
Globular and Open Clusters in our Galaxy
... that most of them are moving around the galactic center in highly eccentric elliptical orbits in any possible inclination, independently from the common Galaxy’s disk rotation. Those orbits form some kind of spherical aureole concentrated around our galactic center, known as the “halo”, but reaching ...
... that most of them are moving around the galactic center in highly eccentric elliptical orbits in any possible inclination, independently from the common Galaxy’s disk rotation. Those orbits form some kind of spherical aureole concentrated around our galactic center, known as the “halo”, but reaching ...
Life of a Star - Amazon Web Services
... the Sun’s life cycle the student will research and lists appropriate Websites for research. The Website links are interactive. If possible, allow students to work from the PDF file on a computer that has Internet access. 5. Re-organize students so that the students working on similar sections of the ...
... the Sun’s life cycle the student will research and lists appropriate Websites for research. The Website links are interactive. If possible, allow students to work from the PDF file on a computer that has Internet access. 5. Re-organize students so that the students working on similar sections of the ...
The discovery based on GLIMPSE data of a protostar driving a
... Yorke 2007; Evans 2011). For low-mass star formation, a widely accepted scenario has been proposed by Shu et al. (1987), in which four distinct evolutionary stages were defined. On the basis of the star formation scenario proposed by Shu et al. (1987), Lada (1987) developed a widely used classificat ...
... Yorke 2007; Evans 2011). For low-mass star formation, a widely accepted scenario has been proposed by Shu et al. (1987), in which four distinct evolutionary stages were defined. On the basis of the star formation scenario proposed by Shu et al. (1987), Lada (1987) developed a widely used classificat ...
Carbon Enhanced Stars in the Sloan Digital Sky Survey ( SDSS )
... SDSS DR4 has about 102,714 stars at a resolution R= 1800 from 3800Å to 9000Å Already about 500 Faint high latitute carbon stars have been identified by Morgan et al. 2002 and Downes et al. 2004. from SDSS DR1 The propermotions indicate that most of them are near by dwarfs. ==> Young population which ...
... SDSS DR4 has about 102,714 stars at a resolution R= 1800 from 3800Å to 9000Å Already about 500 Faint high latitute carbon stars have been identified by Morgan et al. 2002 and Downes et al. 2004. from SDSS DR1 The propermotions indicate that most of them are near by dwarfs. ==> Young population which ...
Test#4
... a) spiral, b) globular, c) elliptical, d) irregular 6. The distribution of galaxies in the universe a) follows the same distribution as stars, b) arraigned on the surfaces of giant bubbles or voids c) fairly uniform, d) has remained the same as it was during the big bang 7. The location of our Sun i ...
... a) spiral, b) globular, c) elliptical, d) irregular 6. The distribution of galaxies in the universe a) follows the same distribution as stars, b) arraigned on the surfaces of giant bubbles or voids c) fairly uniform, d) has remained the same as it was during the big bang 7. The location of our Sun i ...
PDF Format
... exhibited an extraordinarily short period of only about four hours -- the shortest known period to that date. (The correct period is now known to be twice that, just over eight hours.) While brightness variations were evident in the light curve, the type, however, could not be placed amongst the kno ...
... exhibited an extraordinarily short period of only about four hours -- the shortest known period to that date. (The correct period is now known to be twice that, just over eight hours.) While brightness variations were evident in the light curve, the type, however, could not be placed amongst the kno ...
Figure 1. Map showing the region of the Fourth Quadrant selected
... addressing one of the major issues in the understanding of star formation – the role of turbulence in driving and self-regulating it. It will also provide Mopra with an important role in feeding science to the new generation of mm-wave interferometers in the southern hemisphere, firstly with the ATC ...
... addressing one of the major issues in the understanding of star formation – the role of turbulence in driving and self-regulating it. It will also provide Mopra with an important role in feeding science to the new generation of mm-wave interferometers in the southern hemisphere, firstly with the ATC ...
Interpretation of the Helix Planetary Nebula using Hydro
... luminous mass of stars and the more diffusive NBDM-ISM (CDM) mass. The million trillion-planet-PGCs per galaxy each have fossil-density ρ0 ≈ ρP GC ≈ ×104 greater than the hρg i ≈ 10−21 kg m−3 galaxy average and ≈ ×109 hρU i, where hρU i ≈ 10−26 kg m−3 is the flat universe average density at the pr ...
... luminous mass of stars and the more diffusive NBDM-ISM (CDM) mass. The million trillion-planet-PGCs per galaxy each have fossil-density ρ0 ≈ ρP GC ≈ ×104 greater than the hρg i ≈ 10−21 kg m−3 galaxy average and ≈ ×109 hρU i, where hρU i ≈ 10−26 kg m−3 is the flat universe average density at the pr ...
Document
... Dwarf nova: disk instability, outbursts 2-7 mag every week-30 yrs Novalike: high, low states on timescales of months, high accretion ...
... Dwarf nova: disk instability, outbursts 2-7 mag every week-30 yrs Novalike: high, low states on timescales of months, high accretion ...
Planetary nebula
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.