The Sky Tonight - Northern Stars Planetarium
... Aurora Borealis: Displays of flickering lights seen in the northern skies. They are caused by powerful magnetic storms on the Sun. When the energy from these storms reaches Earth, the energy is shielded from us by Earth's magnetic field; however, the energy does interact with the upper atmosphere ne ...
... Aurora Borealis: Displays of flickering lights seen in the northern skies. They are caused by powerful magnetic storms on the Sun. When the energy from these storms reaches Earth, the energy is shielded from us by Earth's magnetic field; however, the energy does interact with the upper atmosphere ne ...
GAIA A Stereoscopic Census of our Galaxy
... – solar neighbourhood mass function and luminosity function e.g. white dwarfs (~200,000) and brown dwarfs (~50,000) – initial mass and luminosity functions in star forming regions – luminosity function for pre main-sequence stars – detection and dating of all spectral types and Galactic populations ...
... – solar neighbourhood mass function and luminosity function e.g. white dwarfs (~200,000) and brown dwarfs (~50,000) – initial mass and luminosity functions in star forming regions – luminosity function for pre main-sequence stars – detection and dating of all spectral types and Galactic populations ...
Lecture 2 Abundances
... • Elements with differences greater than 25% (Table 5, Lodders 2009) are W (2.76), Ag (0.52), Cl (1.79), Rb(1.64), Ga (0.61), Au(1.54). Tl (1.43), Hf (1.43), and F (1.32). Some, like Au, Hf, Mn, and W have uncertain oscillator strengths and problems with line blending. Others, like Cl, Ga, and Rb ar ...
... • Elements with differences greater than 25% (Table 5, Lodders 2009) are W (2.76), Ag (0.52), Cl (1.79), Rb(1.64), Ga (0.61), Au(1.54). Tl (1.43), Hf (1.43), and F (1.32). Some, like Au, Hf, Mn, and W have uncertain oscillator strengths and problems with line blending. Others, like Cl, Ga, and Rb ar ...
Angular momentum and the formation of stars and
... 1997). However, this central density singularity can develop into a star only if most of the angular momentum of the gas orbiting around it is removed. If there are any departures from axial symmetry in this surrounding gas, gravitational torques will be present, and these torques will transport ang ...
... 1997). However, this central density singularity can develop into a star only if most of the angular momentum of the gas orbiting around it is removed. If there are any departures from axial symmetry in this surrounding gas, gravitational torques will be present, and these torques will transport ang ...
Massive close binaries, observational characteristics - UvA-DARE
... If the accretion rate is low, the Alfven radius RA is located far from the neutron star, such that the centrifugal barrier produced by the neutron star's rotation is too great to allow matter at the Alfven surface to enter the magnetosphere and to accrete (cf. Stella, White and Rosner 1986). Therefo ...
... If the accretion rate is low, the Alfven radius RA is located far from the neutron star, such that the centrifugal barrier produced by the neutron star's rotation is too great to allow matter at the Alfven surface to enter the magnetosphere and to accrete (cf. Stella, White and Rosner 1986). Therefo ...
Stellar Temperature and Luminosity Stellar Temperatures and
... To understand how thermal spectra can be used to evaluate the temperature of a star To understand how temperature and radius of a star determine a star’s luminosity Introduction: In this activity we will learn how light from a star can tell us its temperature and how much energy per second the s ...
... To understand how thermal spectra can be used to evaluate the temperature of a star To understand how temperature and radius of a star determine a star’s luminosity Introduction: In this activity we will learn how light from a star can tell us its temperature and how much energy per second the s ...
The importance of radiative feedback for the stellar initial mass
... As each fragment accreted its central density and temperature increased, resulting in smaller and smaller time-steps. When the central density of a fragment exceeded 10−11 g cm−3 , it was replaced by a sink particle. In this paper, the evolution of a collapsing region of gas is similar except that t ...
... As each fragment accreted its central density and temperature increased, resulting in smaller and smaller time-steps. When the central density of a fragment exceeded 10−11 g cm−3 , it was replaced by a sink particle. In this paper, the evolution of a collapsing region of gas is similar except that t ...
Lecture14
... •Suppose you are in a spaceship traveling toward Earth at 95% of the speed of light. Compared to when your ship was at rest on Mars, you measure the length of your ship to be: •A) The same as when it was on Mars •B) Longer than when it was on Mars •C) You can’t tell. Your life processes have slowed ...
... •Suppose you are in a spaceship traveling toward Earth at 95% of the speed of light. Compared to when your ship was at rest on Mars, you measure the length of your ship to be: •A) The same as when it was on Mars •B) Longer than when it was on Mars •C) You can’t tell. Your life processes have slowed ...
Beyond the Solar System By Patti Hutchison ANSWER THE
... Our solar system extends billions of miles from Earth. But there is still something bigger. It is the Milky Way, our galaxy. But wait, there's something even bigger than that- the universe! There are billions of galaxies in space. A galaxy is a group of stars, gas, and dust that are bound together b ...
... Our solar system extends billions of miles from Earth. But there is still something bigger. It is the Milky Way, our galaxy. But wait, there's something even bigger than that- the universe! There are billions of galaxies in space. A galaxy is a group of stars, gas, and dust that are bound together b ...
Understanding the stability of stars by means of thought experiments
... Now, when energy is supplied to the gas in the form of heat, we cannot conclude that this energy rcmains in the gas, since the subsystem "gas" is interacting with the subsystem "weight-and-pulley." Indeed, we have seen that when supplying heat to the gas, its temperature decreases. Since for an idea ...
... Now, when energy is supplied to the gas in the form of heat, we cannot conclude that this energy rcmains in the gas, since the subsystem "gas" is interacting with the subsystem "weight-and-pulley." Indeed, we have seen that when supplying heat to the gas, its temperature decreases. Since for an idea ...
Quasar feedback revealed by giant molecular outflows
... In the standard scenario for galaxy evolution young star-forming galaxies transform into red bulge-dominated spheroids, where star formation has been quenched. To explain this transformation, a strong negative feedback generated by accretion onto a central supermassive black hole is often invoked. T ...
... In the standard scenario for galaxy evolution young star-forming galaxies transform into red bulge-dominated spheroids, where star formation has been quenched. To explain this transformation, a strong negative feedback generated by accretion onto a central supermassive black hole is often invoked. T ...
31-2 - Fremont Peak Observatory
... huge object in absolute terms. Eventually the debris generated by this explosion will be incorporated into new bright nebulae which, in turn, will form new star systems. This will continue the process. The stuff that we are made of was, at one point, in a supernova (or Planetary nebula). ...
... huge object in absolute terms. Eventually the debris generated by this explosion will be incorporated into new bright nebulae which, in turn, will form new star systems. This will continue the process. The stuff that we are made of was, at one point, in a supernova (or Planetary nebula). ...
Evolution of the Highest Redshift Quasars
... – How closely tied are the earliest SBHs and galaxies? Or are we just picking up early starters in term of BH accretion in the most luminous quasars? ...
... – How closely tied are the earliest SBHs and galaxies? Or are we just picking up early starters in term of BH accretion in the most luminous quasars? ...
chapter17StarStuff
... Life Stages of High-Mass Stars • Late life stages of high-mass stars are similar to those of low-mass stars: – Hydrogen core fusion (main sequence) – Hydrogen shell burning (supergiant) – Helium core fusion (supergiant) ...
... Life Stages of High-Mass Stars • Late life stages of high-mass stars are similar to those of low-mass stars: – Hydrogen core fusion (main sequence) – Hydrogen shell burning (supergiant) – Helium core fusion (supergiant) ...
Summary - Chandra X
... magnetically driven by process of elimination. Still, a low density slow thermal wind caused by irradiation heating should produce a mass loss rate 7 times higher than the accretion rate! New simulations of large (~10 pc) scale radiation-driven outflows in AGN (Kurosawa): 3D simulations – clumpy bip ...
... magnetically driven by process of elimination. Still, a low density slow thermal wind caused by irradiation heating should produce a mass loss rate 7 times higher than the accretion rate! New simulations of large (~10 pc) scale radiation-driven outflows in AGN (Kurosawa): 3D simulations – clumpy bip ...
PowerPoint Presentation - ASTR498E High energy
... Means that at least one of the following is true… ...
... Means that at least one of the following is true… ...
Peer-reviewed Article PDF - e
... along with R presents also the revolution periods and the velocities of rotation of the objects in the Solar System but these data are not consistent. It should also be noted that the data on the parameters of planetary orbits are given without errors, which is likely to be connected with not very h ...
... along with R presents also the revolution periods and the velocities of rotation of the objects in the Solar System but these data are not consistent. It should also be noted that the data on the parameters of planetary orbits are given without errors, which is likely to be connected with not very h ...
American Scientist
... notion that one needs more solid material to construct larger cores and trigger runaway accretion of the natal gas. No trend in stellar metallicity is found for the occurrence of rocky exoplanets. When they are found, they tend to be social creatures, located in systems with other rocky brethren. Th ...
... notion that one needs more solid material to construct larger cores and trigger runaway accretion of the natal gas. No trend in stellar metallicity is found for the occurrence of rocky exoplanets. When they are found, they tend to be social creatures, located in systems with other rocky brethren. Th ...
A neutron star with a carbon atmosphere in the Cassiopeia A
... well as our carbon model fit. We fitted the Hwang and Pavlov data simultaneously with several models: a blackbody, a H atmosphere,13 and atmospheres composed of pure He, C, N, or O; these are illustrated in Fig. 2. To identify promising models, the mass and radius of the atmosphere models were fixed ...
... well as our carbon model fit. We fitted the Hwang and Pavlov data simultaneously with several models: a blackbody, a H atmosphere,13 and atmospheres composed of pure He, C, N, or O; these are illustrated in Fig. 2. To identify promising models, the mass and radius of the atmosphere models were fixed ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.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.