Turbulent convection in stellar interiors
... Conclusion and perspectives • MUSIC: new hydro code devoted to the modelling of stellar interiors • Based on implicit time stepping to relax numerical stability limits inherent to stellar hydrodynamical problems • Results in modest, but already useful, speed-up N.B.: the code beats its own explicit ...
... Conclusion and perspectives • MUSIC: new hydro code devoted to the modelling of stellar interiors • Based on implicit time stepping to relax numerical stability limits inherent to stellar hydrodynamical problems • Results in modest, but already useful, speed-up N.B.: the code beats its own explicit ...
CoRoT Observations of O Stars: Diverse Origins of Variability
... At the moment we can only speculate about the possible causes of this red noise in O-type stars. One possibility is that it is caused by the sub-surface convection zone found in theoretical modeling (Cantiello et al. 2009). This zone is assumed to be responsible for a number of surface effects, such ...
... At the moment we can only speculate about the possible causes of this red noise in O-type stars. One possibility is that it is caused by the sub-surface convection zone found in theoretical modeling (Cantiello et al. 2009). This zone is assumed to be responsible for a number of surface effects, such ...
Student Paper (Klongcheongsan)
... luminosity and the effective temperature will have changed. Each of the models used in this research shows that the luminosity and effective temperature increase in agreement with some very recent work by Kippenauer and Wiegert (pp. 271-272). Unfortunately exact values for all parameters are not ce ...
... luminosity and the effective temperature will have changed. Each of the models used in this research shows that the luminosity and effective temperature increase in agreement with some very recent work by Kippenauer and Wiegert (pp. 271-272). Unfortunately exact values for all parameters are not ce ...
kaekae14 dae dae15 lifecycleofastar
... cloud picks up stellar dust and other space junk the increasing gravity causes the cloud to collapse. As it collapses the cloud becomes smaller and hotter. After a few million years the low mass star begins to fuse helium into hydrogen. When this happens the collapse is ended because the fusion rais ...
... cloud picks up stellar dust and other space junk the increasing gravity causes the cloud to collapse. As it collapses the cloud becomes smaller and hotter. After a few million years the low mass star begins to fuse helium into hydrogen. When this happens the collapse is ended because the fusion rais ...
ASTR3007/4007/6007, Class 1: Observing the Stars 23 February
... The HR diagram is an extremely simple plot. We simply find a bunch of stars, measure their luminosities and surface temperatures, and make a scatter plot of one against the other. Since surface temperatures and absolute luminosities are often expensive to measure in practice, more often we plot clos ...
... The HR diagram is an extremely simple plot. We simply find a bunch of stars, measure their luminosities and surface temperatures, and make a scatter plot of one against the other. Since surface temperatures and absolute luminosities are often expensive to measure in practice, more often we plot clos ...
ultracam observations of pulsating sdB stars
... origin of sdB stars Binary evolution is important in at least 2/3 of sdBs (Green, Liebert & Saffer, 2001, ASP 226). Key factor is Roche Lobe Overflow in metal-rich low-mass giants near the Red Giant Tip. Group III (composite) sdBs are the key: i. low-mass binary with initial separation 415-520 R ii ...
... origin of sdB stars Binary evolution is important in at least 2/3 of sdBs (Green, Liebert & Saffer, 2001, ASP 226). Key factor is Roche Lobe Overflow in metal-rich low-mass giants near the Red Giant Tip. Group III (composite) sdBs are the key: i. low-mass binary with initial separation 415-520 R ii ...
Where Stars Are Born
... 1. What is the composition of interstellar gas? Of interstellar dust? 2. If space is a near-perfect vacuum, how can there be enough dust in it to block light? 3. What is an emission nebula? 4. How is interstellar dust detected? 5. Why is dust found in the neighborhood of some stars (as in the Pleiad ...
... 1. What is the composition of interstellar gas? Of interstellar dust? 2. If space is a near-perfect vacuum, how can there be enough dust in it to block light? 3. What is an emission nebula? 4. How is interstellar dust detected? 5. Why is dust found in the neighborhood of some stars (as in the Pleiad ...
Slide 1
... collapsing down and crushing the core of the star. As long as we have nuclear fusion pushing out, our star can fight off gravity. ...
... collapsing down and crushing the core of the star. As long as we have nuclear fusion pushing out, our star can fight off gravity. ...
Слайд 1 - Astroplate
... The progenitor of V838 Mon was a binary system of B type stars. We were able to separate contributions of both components in common light as the light lost in explosion or in eclipse. In the first case, exploded star remnant disappeared from B and V bands because its spectrum shifted to the red due ...
... The progenitor of V838 Mon was a binary system of B type stars. We were able to separate contributions of both components in common light as the light lost in explosion or in eclipse. In the first case, exploded star remnant disappeared from B and V bands because its spectrum shifted to the red due ...
Chapter 12
... larger one radiates more energy than the smaller one • In stellar terms: a star of larger radius will have a higher luminosity than a smaller star at the same temperature ...
... larger one radiates more energy than the smaller one • In stellar terms: a star of larger radius will have a higher luminosity than a smaller star at the same temperature ...
Goal: To understand the HR diagram
... • At different temperatures, the blackbody spectrum peaks out at a different part of the spectrum. • Hot stars peak in the blue – so they appear to be blue. • Moderate stars peak in the middle, so appear to be yellow to white. • Cooler stars peak in the red, so appear to be orange to red. ...
... • At different temperatures, the blackbody spectrum peaks out at a different part of the spectrum. • Hot stars peak in the blue – so they appear to be blue. • Moderate stars peak in the middle, so appear to be yellow to white. • Cooler stars peak in the red, so appear to be orange to red. ...
Document
... a. Halted by degeneracy pressure in the core. b. Halted when the atoms are pushed up against one another and contraction stops. c. Finally balanced by outward thermal pressure from nuclear reactions. d. Finally balanced by radiation emitted in the photosphere. e. none of the above. ...
... a. Halted by degeneracy pressure in the core. b. Halted when the atoms are pushed up against one another and contraction stops. c. Finally balanced by outward thermal pressure from nuclear reactions. d. Finally balanced by radiation emitted in the photosphere. e. none of the above. ...
The Sun Like Star : HT Vir
... The light curves and data in the V band of HT Vir variable in the ASAS catalog have been taken into account (Pojmanski, 1997). The graphics according to the time (HJD) of the magnitudes (Vmag) is given in Figure1. The light curve according to phase of the stars is given in Figure2. The light curve c ...
... The light curves and data in the V band of HT Vir variable in the ASAS catalog have been taken into account (Pojmanski, 1997). The graphics according to the time (HJD) of the magnitudes (Vmag) is given in Figure1. The light curve according to phase of the stars is given in Figure2. The light curve c ...
Astronomy 112: The Physics of Stars Class 11 Notes: Stellar
... contrast, instability occurs when any small deviation from an equilibrium solution tends to drive the system further and further away from it. The classic example of an unstable system is a pencil standing on its point. If one could get the pencil to balance completely perfectly, it would be in equi ...
... contrast, instability occurs when any small deviation from an equilibrium solution tends to drive the system further and further away from it. The classic example of an unstable system is a pencil standing on its point. If one could get the pencil to balance completely perfectly, it would be in equi ...
Stellar Evolu1on Stars spend most of their lives on the main
... phase, is driven by the conversion of hydrogen into helium in their cores. Stars expand and become more luminous while on the main-‐sequence -‐> the conversion of hydrogen into helium changes the chem ...
... phase, is driven by the conversion of hydrogen into helium in their cores. Stars expand and become more luminous while on the main-‐sequence -‐> the conversion of hydrogen into helium changes the chem ...
Radiation vs. Gas Pressure, the Stellar Mass
... We can also use these two basic equations of stellar structure – viz. hydrostatic equilibrium and radiative diffusion – to derive the basic scaling laws for the variation of stellar luminosity with mass. For simplicity, let us first consider cases well below the Eddington limit, Γ ≪ 1, at which the ...
... We can also use these two basic equations of stellar structure – viz. hydrostatic equilibrium and radiative diffusion – to derive the basic scaling laws for the variation of stellar luminosity with mass. For simplicity, let us first consider cases well below the Eddington limit, Γ ≪ 1, at which the ...
Stars and The Universe
... itself, its mass collides at its core and bounces back in an explosion called a ____________. As a result of this explosion, parts of the massive star fly away into space, where they can form _____________. If the mass remaining in the dead star’s core is 3 times our sun’s mass, it will form a _____ ...
... itself, its mass collides at its core and bounces back in an explosion called a ____________. As a result of this explosion, parts of the massive star fly away into space, where they can form _____________. If the mass remaining in the dead star’s core is 3 times our sun’s mass, it will form a _____ ...
THE PHYSICAL CHARACTERIZATION OF THE STARS 1
... The Spectral Energy Distribution Fit (SEDF) method proposed by [22] follows a somewhat different approach, namely the fit of the stellar spectral energy distribution from the optical (V ) to the IR (JHK) using synthetic photometry computed from stellar atmosphere models. Unlike the implementation of ...
... The Spectral Energy Distribution Fit (SEDF) method proposed by [22] follows a somewhat different approach, namely the fit of the stellar spectral energy distribution from the optical (V ) to the IR (JHK) using synthetic photometry computed from stellar atmosphere models. Unlike the implementation of ...
When you look up at the night sky, thousands of objects
... All the matter and energy in the universe is contained in a volume of space that scientists have discovered is constantly expanding. The expanding universe is similar to a balloon that is constantly inflating. Scientists do not know how large the universe is now. However, they have gathered evidence ...
... All the matter and energy in the universe is contained in a volume of space that scientists have discovered is constantly expanding. The expanding universe is similar to a balloon that is constantly inflating. Scientists do not know how large the universe is now. However, they have gathered evidence ...
Unit 8 Chapter 30 Stars, Galaxies and the Universe
... Our sun would be a 4.8, average star, Rigel has an Absolute Magnitude of 6.4 which makes it appear brighter than most stars. Remember, all stars are not the same distance away, therefore, a faint star may really be very bright if it were closer. ...
... Our sun would be a 4.8, average star, Rigel has an Absolute Magnitude of 6.4 which makes it appear brighter than most stars. Remember, all stars are not the same distance away, therefore, a faint star may really be very bright if it were closer. ...
the life cycle of stars - North American Montessori Center
... predicted by Albert Einstein’s famous equation, E=MC2, which means: “energy equals mass times the speed of light squared.” That little bit of mass is the fuel that the protostar burns, turning it into light and heat in the form of photons, particles of light energy. When nucleosynthesis begins in a ...
... predicted by Albert Einstein’s famous equation, E=MC2, which means: “energy equals mass times the speed of light squared.” That little bit of mass is the fuel that the protostar burns, turning it into light and heat in the form of photons, particles of light energy. When nucleosynthesis begins in a ...
1 Josh Machado Science Section C. Language Arts Section E. 5/15
... Nebula. Stars have been studied for thousands of years. Mankind has always longed for a deeper understanding of the world around us, which includes all the mysteries beyond our home planet. Learning about stars helps us in our understanding of the universe. Stars, believe it or not, help explain eve ...
... Nebula. Stars have been studied for thousands of years. Mankind has always longed for a deeper understanding of the world around us, which includes all the mysteries beyond our home planet. Learning about stars helps us in our understanding of the universe. Stars, believe it or not, help explain eve ...
Stars part 2
... By the end of this presentation, students will be able to • explain the role of nuclear fusion in the sun’s core to release energy; • communicate scientific ideas about the way stars, over their life cycle, produce elements; • illustrate the life span of the sun. ...
... By the end of this presentation, students will be able to • explain the role of nuclear fusion in the sun’s core to release energy; • communicate scientific ideas about the way stars, over their life cycle, produce elements; • illustrate the life span of the sun. ...
Stellar Evolution in the HR Diagram
... timescale. As the area outside the shell is pushed farther away by radiation pressure, it begins to cool. The area becomes more opaque because of Kramer’s law (κ ∝ T-7.5). • The higher opacity of the envelope traps the energy, which does PdV work on its surroundings, causing the gas to expand. This ...
... timescale. As the area outside the shell is pushed farther away by radiation pressure, it begins to cool. The area becomes more opaque because of Kramer’s law (κ ∝ T-7.5). • The higher opacity of the envelope traps the energy, which does PdV work on its surroundings, causing the gas to expand. This ...
Lecture 6 - Stars and Distances
... match” for this candidate. A signal that drifts so quickly that it can only be heard for seconds at a time at a given frequency can only be detected by blind luck. Needless to say, such a transmission is an unlikely vehicle for message from an advanced ...
... match” for this candidate. A signal that drifts so quickly that it can only be heard for seconds at a time at a given frequency can only be detected by blind luck. Needless to say, such a transmission is an unlikely vehicle for message from an advanced ...