Document
... From models of stellar interiors. • Tsurface Mass relations. • Convert SED to magnitudes in different colour bands. • Account for distance dimming, Lbol spread over sphere. • Reddening from ISM. ...
... From models of stellar interiors. • Tsurface Mass relations. • Convert SED to magnitudes in different colour bands. • Account for distance dimming, Lbol spread over sphere. • Reddening from ISM. ...
PowerPoint on Astrolabe
... clock. Put your thumb over the current month. Hold your Star Clock so the current month is AT THE TOP. 6. Turn the smaller disc until its stars line up with those in the sky. 7. Read the time in the window. ...
... clock. Put your thumb over the current month. Hold your Star Clock so the current month is AT THE TOP. 6. Turn the smaller disc until its stars line up with those in the sky. 7. Read the time in the window. ...
Constellations Across the Seasons Astronomy in Navigation and
... Stars that are beyond the solar system can be seen in the night sky in patterns called constellations. Constellations can be used for navigation and appear to move together across the sky because of Earth’s rotation. Students should evaluate informational texts, observations, and data collected abou ...
... Stars that are beyond the solar system can be seen in the night sky in patterns called constellations. Constellations can be used for navigation and appear to move together across the sky because of Earth’s rotation. Students should evaluate informational texts, observations, and data collected abou ...
IPHAS: Surveying the Northern Galactic Plane in Hα
... early-type stars, red points are mostly G and K stars, while dark blue points are M stars. The magenta points are strong Hα absorbers, in fact they are white dwarfs, while the green points are emission line stars, in fact Be stars. Note that the trend from early-type to late-type stars is well repro ...
... early-type stars, red points are mostly G and K stars, while dark blue points are M stars. The magenta points are strong Hα absorbers, in fact they are white dwarfs, while the green points are emission line stars, in fact Be stars. Note that the trend from early-type to late-type stars is well repro ...
Sunspots - Sage Middle School
... are related? The temperature of our Sun gives it its yellowish color! ...
... are related? The temperature of our Sun gives it its yellowish color! ...
T Tauri Stars
... Are winds originating in disks or is there another explanation for this correlation What are the transport mechanisms for mass infall? Why are CTTSs so aperiodic? What causes the massive flaring of FU Orionis outbursts? ...
... Are winds originating in disks or is there another explanation for this correlation What are the transport mechanisms for mass infall? Why are CTTSs so aperiodic? What causes the massive flaring of FU Orionis outbursts? ...
Gravitational Waves from Neutron Stars
... If S ( r ) > 0 the fluid element oscillate about the equilibrium position: a g-mode appears If S ( r ) < 0 there is a convective instability If S ( r ) = 0 (as it is for a T=0 star) g-modes degenerate at zero frequency g-modes appear if there are thermal or composition gradients ...
... If S ( r ) > 0 the fluid element oscillate about the equilibrium position: a g-mode appears If S ( r ) < 0 there is a convective instability If S ( r ) = 0 (as it is for a T=0 star) g-modes degenerate at zero frequency g-modes appear if there are thermal or composition gradients ...
Power Point of Slides I never Got to
... For stars, the more massive, the more quickly they use up their fuel so the most massive stars only live about 1 million years on the main sequence and are therefore “young” on star time scales => 12-15 billion is good number but uncertainty is enough with a low H0 to fit even L = 0 models. Remember ...
... For stars, the more massive, the more quickly they use up their fuel so the most massive stars only live about 1 million years on the main sequence and are therefore “young” on star time scales => 12-15 billion is good number but uncertainty is enough with a low H0 to fit even L = 0 models. Remember ...
1_Introduction - Department of Astronomy
... As the gas of the molecular cloud is compressed, it becomes denser. As the gas is compressed, it also becomes hotter. When the gas temperature is high enough (T ≈ 10 million Kelvin), nuclear fusion begins! ...
... As the gas of the molecular cloud is compressed, it becomes denser. As the gas is compressed, it also becomes hotter. When the gas temperature is high enough (T ≈ 10 million Kelvin), nuclear fusion begins! ...
Lecture 33
... If you don't like the Universe, just wait a minute.... :-) • The universe had to expand by more than another order of magnitude in order to cool so that neutrons and protons could combine; before that any that formed were immediately broken apart again by high-energy photons. • Thus, starting at t~ ...
... If you don't like the Universe, just wait a minute.... :-) • The universe had to expand by more than another order of magnitude in order to cool so that neutrons and protons could combine; before that any that formed were immediately broken apart again by high-energy photons. • Thus, starting at t~ ...
Astronomy 1001/1005 Final Exam (250 points)
... Elliptical Galaxies are simple spheroidal collections of stars. The stars are usually very old as ellipticals are devoid of gas and dust, preventing ongoing star formation. Irregular Galaxies are galaxies that do not fall into either of the previous two categories. The come in all shapes and sizes a ...
... Elliptical Galaxies are simple spheroidal collections of stars. The stars are usually very old as ellipticals are devoid of gas and dust, preventing ongoing star formation. Irregular Galaxies are galaxies that do not fall into either of the previous two categories. The come in all shapes and sizes a ...
N(M)
... prob of spontaneous flip = 1 in few million yrs, (highly forbidden) but there is a lot of H! ...
... prob of spontaneous flip = 1 in few million yrs, (highly forbidden) but there is a lot of H! ...
PowerPoint Presentation - Mullard Space Science Laboratory
... The possibility of formation of quark-gluon plasmas (QGP) in heavy-ion collisions leads to a suggestion that phase transition might occur in the dense interiors of neutron stars [1,2]. At temperatures T ~ 0 - 40 MeV, there are two possibilities for phase transitions (see the QGP diagram showing quan ...
... The possibility of formation of quark-gluon plasmas (QGP) in heavy-ion collisions leads to a suggestion that phase transition might occur in the dense interiors of neutron stars [1,2]. At temperatures T ~ 0 - 40 MeV, there are two possibilities for phase transitions (see the QGP diagram showing quan ...
ph507lecnote07
... Our Sun is the nearest star. The fascinating properties and phenomena of the solar surface layers are easily observed and have been studied intensely. Unfortunately, models for understanding solar phenomena have not kept pace with such detailed data. Because the Sun is a fairly typical star and beca ...
... Our Sun is the nearest star. The fascinating properties and phenomena of the solar surface layers are easily observed and have been studied intensely. Unfortunately, models for understanding solar phenomena have not kept pace with such detailed data. Because the Sun is a fairly typical star and beca ...
The Universe and Big Bang Theory Review Sheet
... - It suggests the universe is expanding. 6. The farther the galaxy is from earth, the greater the red shift. 7. From where do stars originate from? -from clouds of gas and dust clouds. 8. How does gravity play a role in the forming of stars? - gravity causes the gas and dust clouds to clump up, form ...
... - It suggests the universe is expanding. 6. The farther the galaxy is from earth, the greater the red shift. 7. From where do stars originate from? -from clouds of gas and dust clouds. 8. How does gravity play a role in the forming of stars? - gravity causes the gas and dust clouds to clump up, form ...
Observational Lower mass limit on stars
... Two important factors that will help to constrain the minimum masses of stars are the metallicity and mixing length. The lower the metallicity of a star, the greater minimum mass that star can have. Objects with lower metallicity evolve at greater luminosities and effective temperatures (Chabrier & ...
... Two important factors that will help to constrain the minimum masses of stars are the metallicity and mixing length. The lower the metallicity of a star, the greater minimum mass that star can have. Objects with lower metallicity evolve at greater luminosities and effective temperatures (Chabrier & ...
Lecture 16: Iron Core Collapse, Neutron Stars, and Nucleosynthesis
... forming an iron core (b) that reaches Chandrasekhar-mass and starts to collapse. The inner part of the core is compressed greater than nuclear density (c), causing infalling material to bounce (d) and form an outward-propagating shock front (red). The shock starts to stall (e), but it is re-invigora ...
... forming an iron core (b) that reaches Chandrasekhar-mass and starts to collapse. The inner part of the core is compressed greater than nuclear density (c), causing infalling material to bounce (d) and form an outward-propagating shock front (red). The shock starts to stall (e), but it is re-invigora ...
Modern Physics Exam
... A star containing hydrogen would have intense peaks of energy at 410.17 nm, 434.05 nm, 486.13 nm, and 656.28 nm. These hydrogen emission peaks would be in addition to the ones associated with the other elements contained in the star. In the 1920's, Edwin Hubble, while studying the stars of distant g ...
... A star containing hydrogen would have intense peaks of energy at 410.17 nm, 434.05 nm, 486.13 nm, and 656.28 nm. These hydrogen emission peaks would be in addition to the ones associated with the other elements contained in the star. In the 1920's, Edwin Hubble, while studying the stars of distant g ...
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 ...
Nuclear Reactions Radioactive Decay The stability of an isotope
... U + 1n → 92Kr + 141Ba + 3 1n + energy When U-235 is struck by a neutron, it produces 3 more neutrons which then can react with other uranium atoms creating a chain reaction that can produce massive amounts of energy in under a microsecond. This process is called Nuclear Fission, and is the principle ...
... U + 1n → 92Kr + 141Ba + 3 1n + energy When U-235 is struck by a neutron, it produces 3 more neutrons which then can react with other uranium atoms creating a chain reaction that can produce massive amounts of energy in under a microsecond. This process is called Nuclear Fission, and is the principle ...
Stability of hot neutron stars
... slowingdown of its rotation after the freezing of thermonuclear equilibrium. The change of nuclear compositions, which takes place during the compression, has been investigated. If the initial species of nuclei is 56Fe, the charge and the mass number of nuclei decrease as a result of repeated electr ...
... slowingdown of its rotation after the freezing of thermonuclear equilibrium. The change of nuclear compositions, which takes place during the compression, has been investigated. If the initial species of nuclei is 56Fe, the charge and the mass number of nuclei decrease as a result of repeated electr ...
The Most Massive LMC Star Sk
... relatively small number of stars, can sigfound that vibrations produce shock nificantly alter the shape of the upper waves in the star's gas wh ich could part of the IMF. Very roughly, one star in damp down the vibrational instability. A a billion may be above 60 MG' The annon-linear treatment of vi ...
... relatively small number of stars, can sigfound that vibrations produce shock nificantly alter the shape of the upper waves in the star's gas wh ich could part of the IMF. Very roughly, one star in damp down the vibrational instability. A a billion may be above 60 MG' The annon-linear treatment of vi ...
Maximum Mass Limit of Stars on the Main Sequence
... of these objects. Essentially, there are no conclusive observations that indicate whether a slow or a fast method applies to this type of stellar formation. Regardless of the approach, some of the gas in these filaments can become gravitationally bound and begin the collapse necessary to begin the ...
... of these objects. Essentially, there are no conclusive observations that indicate whether a slow or a fast method applies to this type of stellar formation. Regardless of the approach, some of the gas in these filaments can become gravitationally bound and begin the collapse necessary to begin the ...
Supernovae
... rebound in which the outer parts of the star are blown away The visible/X-ray supernova results due to radiation from this exploded material and later from shock-heated interstellar ...
... rebound in which the outer parts of the star are blown away The visible/X-ray supernova results due to radiation from this exploded material and later from shock-heated interstellar ...
Main sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or ""dwarf"" stars.After a star has formed, it generates thermal energy in the dense core region through the nuclear fusion of hydrogen atoms into helium. During this stage of the star's lifetime, it is located along the main sequence at a position determined primarily by its mass, but also based upon its chemical composition and other factors. All main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy generation in the core on the temperature and pressure helps to sustain this balance. Energy generated at the core makes its way to the surface and is radiated away at the photosphere. The energy is carried by either radiation or convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.The main sequence is sometimes divided into upper and lower parts, based on the dominant process that a star uses to generate energy. Stars below about 1.5 times the mass of the Sun (or 1.5 solar masses (M☉)) primarily fuse hydrogen atoms together in a series of stages to form helium, a sequence called the proton–proton chain. Above this mass, in the upper main sequence, the nuclear fusion process mainly uses atoms of carbon, nitrogen and oxygen as intermediaries in the CNO cycle that produces helium from hydrogen atoms. Main-sequence stars with more than two solar masses undergo convection in their core regions, which acts to stir up the newly created helium and maintain the proportion of fuel needed for fusion to occur. Below this mass, stars have cores that are entirely radiative with convective zones near the surface. With decreasing stellar mass, the proportion of the star forming a convective envelope steadily increases, whereas main-sequence stars below 0.4 M☉ undergo convection throughout their mass. When core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.In general, the more massive a star is, the shorter its lifespan on the main sequence. After the hydrogen fuel at the core has been consumed, the star evolves away from the main sequence on the HR diagram. The behavior of a star now depends on its mass, with stars below 0.23 M☉ becoming white dwarfs directly, whereas stars with up to ten solar masses pass through a red giant stage. More massive stars can explode as a supernova, or collapse directly into a black hole.