Grade - Amazon S3
... PO 4. Analyze the following factors that affect climate: ocean currents elevation location PO 5. Analyze the impact of large-scale weather systems on the local weather. ...
... PO 4. Analyze the following factors that affect climate: ocean currents elevation location PO 5. Analyze the impact of large-scale weather systems on the local weather. ...
Luminous Blue Variables are Antisocial: Their Isolation Implies that
... Smith et al. 2004; Clark et al. 2005). Stars that spectroscopically resemble LBVs with similar luminosity and color, but which have not (as yet) been observed to show the signature eruptive variability of LBVs, are often called “LBV candidates”; these are presumed to be temporarily dormant LBVs. The ...
... Smith et al. 2004; Clark et al. 2005). Stars that spectroscopically resemble LBVs with similar luminosity and color, but which have not (as yet) been observed to show the signature eruptive variability of LBVs, are often called “LBV candidates”; these are presumed to be temporarily dormant LBVs. The ...
Open clusters and associations in the Gaia era
... an issue if the survey does not extend beyond the cluster tidal radius, especially if there is mass segregation as the incompleteness level will then depend on mass. Moreover, objects might be missed around bright stars due to contrast issue, in crowded regions or in area with high extinction. As fo ...
... an issue if the survey does not extend beyond the cluster tidal radius, especially if there is mass segregation as the incompleteness level will then depend on mass. Moreover, objects might be missed around bright stars due to contrast issue, in crowded regions or in area with high extinction. As fo ...
L95 IRON-RICH EJECTA IN THE SUPERNOVA
... the Fe and Si-group elements as a function of radius in the core region. For simplicity, we assume a spherical geometry for the deprojection. If the true three-dimensional shape of the core region were ellipsoidal, then our mass estimates would be some 13% higher (prolate) or lower (oblate). We assu ...
... the Fe and Si-group elements as a function of radius in the core region. For simplicity, we assume a spherical geometry for the deprojection. If the true three-dimensional shape of the core region were ellipsoidal, then our mass estimates would be some 13% higher (prolate) or lower (oblate). We assu ...
exploring anticorrelations and light element variations
... poorly studied (NGC 5466), or have been only recently discussed in the literature, such as M2 (Yong et al. 2014). ...
... poorly studied (NGC 5466), or have been only recently discussed in the literature, such as M2 (Yong et al. 2014). ...
PART TWO: No Singularity inside Black Holes (BH)
... (E). The exchange of energy-matters through Event Horizon, unstableness of the Event Horizon of BH In any BH (Mb) (5Mθ>Mb>1015g), energy emissions are extremely low. The exchange of energy-matters passed only through Event Horizon would lead to Event Horizon oscillated. From formulas (11a) Rb = 2GMb ...
... (E). The exchange of energy-matters through Event Horizon, unstableness of the Event Horizon of BH In any BH (Mb) (5Mθ>Mb>1015g), energy emissions are extremely low. The exchange of energy-matters passed only through Event Horizon would lead to Event Horizon oscillated. From formulas (11a) Rb = 2GMb ...
Pulsed Accretion in the Young Binary &
... low fractional levels over the course of 10 Myr or less. Accretion would also be enhanced by a smaller binary separation and a smaller orbital period (Ostriker et al. 1992). But recently, White and Ghez (2001) found that the mass accretion rates for primary stars are similar to single stars, which s ...
... low fractional levels over the course of 10 Myr or less. Accretion would also be enhanced by a smaller binary separation and a smaller orbital period (Ostriker et al. 1992). But recently, White and Ghez (2001) found that the mass accretion rates for primary stars are similar to single stars, which s ...
Seminar 2
... sample varies by a factor of 6. These variations could possibly be explained by a relation between total stellar mass and mass to light ratio and thus the differences in stellar mass would give these variations. Another important conclusion is that at high redshifts the red and dead galaxies are the ...
... sample varies by a factor of 6. These variations could possibly be explained by a relation between total stellar mass and mass to light ratio and thus the differences in stellar mass would give these variations. Another important conclusion is that at high redshifts the red and dead galaxies are the ...
Formation of the First Galaxies: Theory and Simulations
... and evolution of stars. By this definition, the formation sites of the first stars, dark matter minihalos with masses 105 - 106 M⊙ , are unlikely candidates for the first galaxies, as the high energy radiation emitted by young stars and the supernovae that mark their end of life can rarify and expel ...
... and evolution of stars. By this definition, the formation sites of the first stars, dark matter minihalos with masses 105 - 106 M⊙ , are unlikely candidates for the first galaxies, as the high energy radiation emitted by young stars and the supernovae that mark their end of life can rarify and expel ...
Astronomy Astrophysics Astrophysical parameters and orbital solution of the peculiar X-ray
... Roche 1999), showing much less X-ray variability and lower luminosities (LX 1035 erg s−1 ; Reig 2011). In SGXBs the optical companion is an OB supergiant. Supergiant stars are known to suffer great mass loss in the form of a radiation-driven stellar wind (Kudritzki & Puls 2000). The compact star in ...
... Roche 1999), showing much less X-ray variability and lower luminosities (LX 1035 erg s−1 ; Reig 2011). In SGXBs the optical companion is an OB supergiant. Supergiant stars are known to suffer great mass loss in the form of a radiation-driven stellar wind (Kudritzki & Puls 2000). The compact star in ...
A DEBRIS disk around the planet hosting M
... Almost all debris disks detected by the satellites IRAS, ISO and Spitzer (Bryden et al. 2006; Su et al. 2006; Trilling et al. 2008), Hubble Space Telescope (HST; Golimowski et al. 2011), and ground-based telescopes (Wyatt 2008) surround A-type and F, G, K-type stars despite several deep surveys of l ...
... Almost all debris disks detected by the satellites IRAS, ISO and Spitzer (Bryden et al. 2006; Su et al. 2006; Trilling et al. 2008), Hubble Space Telescope (HST; Golimowski et al. 2011), and ground-based telescopes (Wyatt 2008) surround A-type and F, G, K-type stars despite several deep surveys of l ...
High Energy Astrophysics T. J.
... At present high energy astrophysics is a very lively part of astrophysics. This is due to the fact that the subject did only really start after the beginning of the space age in the 1960s, to a steady progress in the instrumentation available and to an unprecedented set of instruments in orbit now. ...
... At present high energy astrophysics is a very lively part of astrophysics. This is due to the fact that the subject did only really start after the beginning of the space age in the 1960s, to a steady progress in the instrumentation available and to an unprecedented set of instruments in orbit now. ...
Measuring Reddening with SDSS Stellar Spectra and Recalibrating
... using a variety of methods, including ones that are independent of the observed colors of the star. We use one such method to predict the intrinsic colors of each star. The difference between the observed colors and intrinsic colors is used as a measurement of reddening to each star. These reddening ...
... using a variety of methods, including ones that are independent of the observed colors of the star. We use one such method to predict the intrinsic colors of each star. The difference between the observed colors and intrinsic colors is used as a measurement of reddening to each star. These reddening ...
xrayecc
... is lost and transferred onto the degenerate companion. This often involves the formation of a disk of accreting matter about the companion, which spirals onto the star. In larger mass systems, a second mechanism tends to dominate. This is wind driven transfer. Giant stars can lose material from thei ...
... is lost and transferred onto the degenerate companion. This often involves the formation of a disk of accreting matter about the companion, which spirals onto the star. In larger mass systems, a second mechanism tends to dominate. This is wind driven transfer. Giant stars can lose material from thei ...
GAIA A Stereoscopic Census of our Galaxy - Cosmos
... 7 µarcsec at G = 10 mag 26 µarcsec at G = 15 mag 600 µarcsec at G = 20 mag Low-res. spectra to G = 20 mag 15 km s-1 to GRVS = 16 mag Complete and unbiased ...
... 7 µarcsec at G = 10 mag 26 µarcsec at G = 15 mag 600 µarcsec at G = 20 mag Low-res. spectra to G = 20 mag 15 km s-1 to GRVS = 16 mag Complete and unbiased ...
Stellar evolution
Stellar evolution is the process by which a star changes during its lifetime. Depending on the mass of the star, this lifetime ranges from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more-massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.