Chapter 14
... 16. Which of the following describes the gravitational red shift? a. The reddening of starlight by interstellar dust grains. b. A reduction in the energy of photons as they move away from objects. c. The angular change in a star's position when observed during a solar eclipse. d. The alternating Dop ...
... 16. Which of the following describes the gravitational red shift? a. The reddening of starlight by interstellar dust grains. b. A reduction in the energy of photons as they move away from objects. c. The angular change in a star's position when observed during a solar eclipse. d. The alternating Dop ...
Eyeing the retina nebula
... Planetary nebulae are the multicolored remnants of dead stars. When a star about the size of the Sun runs out of nuclear fuel, the core collapses to form a much smaller dwarf star and the outer layers are ejected to form an expanding cloud of dust and gas. Intense radiation from the collapsed star i ...
... Planetary nebulae are the multicolored remnants of dead stars. When a star about the size of the Sun runs out of nuclear fuel, the core collapses to form a much smaller dwarf star and the outer layers are ejected to form an expanding cloud of dust and gas. Intense radiation from the collapsed star i ...
Chapter 6 Stars
... are the remains of high-mass stars. They are even smaller and denser than white dwarfs. A neutron star may contain as much as three times the mass of the sun but be only about 25 kilometers in diameter, the size of a city! In 1967, Jocelyn Bell, a British astronomy student, detected an object in spa ...
... are the remains of high-mass stars. They are even smaller and denser than white dwarfs. A neutron star may contain as much as three times the mass of the sun but be only about 25 kilometers in diameter, the size of a city! In 1967, Jocelyn Bell, a British astronomy student, detected an object in spa ...
Astronomical Distance Determination • etc.
... Cepheids The oscillation only occurs when the temperature structure of the star is such that the helium ionization zone lies near the stellar surface. Doubly ionized helium is more opaque than singly ionized helium. The pulsation is due to properties of the envelope and does not involve the nuclea ...
... Cepheids The oscillation only occurs when the temperature structure of the star is such that the helium ionization zone lies near the stellar surface. Doubly ionized helium is more opaque than singly ionized helium. The pulsation is due to properties of the envelope and does not involve the nuclea ...
script
... 2. High level of activity (Ca II emission): Related to (1) as stars that rotate rapidly also generate more magnetic fields 1. Strong lithium line. Lithium is destroyed at temperatures of a few million K. The star starts with lithium present, but through time convection brings it to the bottom of the ...
... 2. High level of activity (Ca II emission): Related to (1) as stars that rotate rapidly also generate more magnetic fields 1. Strong lithium line. Lithium is destroyed at temperatures of a few million K. The star starts with lithium present, but through time convection brings it to the bottom of the ...
Neutron Stars and Black Holes
... 16. Which of the following describes the gravitational red shift? a. The reddening of starlight by interstellar dust grains. b. A reduction in the energy of photons as they move away from objects. c. The angular change in a star's position when observed during a solar eclipse. d. The alternating Dop ...
... 16. Which of the following describes the gravitational red shift? a. The reddening of starlight by interstellar dust grains. b. A reduction in the energy of photons as they move away from objects. c. The angular change in a star's position when observed during a solar eclipse. d. The alternating Dop ...
5. Energy Production and Transport
... larger binding energy per nucleon than the original nuclei. As the total number of nucleons has not been changed, such nuclear fusion reactions must release energy. Once the compound nucleus lies in the iron region of Fig. 1 however, further energy release from fusion reactions becomes impossible. T ...
... larger binding energy per nucleon than the original nuclei. As the total number of nucleons has not been changed, such nuclear fusion reactions must release energy. Once the compound nucleus lies in the iron region of Fig. 1 however, further energy release from fusion reactions becomes impossible. T ...
The Early Evolution of Protostars
... The initial conditions for planet formation may be determined by time since last episode of disk instability ...
... The initial conditions for planet formation may be determined by time since last episode of disk instability ...
Notes 3 - 1 Notes 3: Formation of the solar system 3.1 Starting
... is primarily on the inner part of the disk forming around the star. While the T Tauri stage is a good cleaning-up stage for the solar system, there are also other things happening in the disk of the star. Disks of material have been observed around many stars since the first one was discovered aroun ...
... is primarily on the inner part of the disk forming around the star. While the T Tauri stage is a good cleaning-up stage for the solar system, there are also other things happening in the disk of the star. Disks of material have been observed around many stars since the first one was discovered aroun ...
HR Diagram - TeacherWeb
... 2. Organize: Compare the colors of the following stars in the Star collection: Aldebaran, Betelgeuse, Sirius B, Spica, the Sun, and Vega. Drag the six stars to position them where you think they would fit on the Gizmo’s color scale. Click Sort stars on the Gizmo to check your placements. Mark the lo ...
... 2. Organize: Compare the colors of the following stars in the Star collection: Aldebaran, Betelgeuse, Sirius B, Spica, the Sun, and Vega. Drag the six stars to position them where you think they would fit on the Gizmo’s color scale. Click Sort stars on the Gizmo to check your placements. Mark the lo ...
–1– 3. Equation of State In the stellar interior, as we shall see, the
... For a typical main sequence star, X = 0.7, Y = 0.28, and Z = 0.02. Hence, most mass is in hydrogen and helium, while a very small fraction is in heavier elements. In most stellar applications, it is safe to assume that the stars are fully ionised, the only exceptions are stellar atmospheres. So the ...
... For a typical main sequence star, X = 0.7, Y = 0.28, and Z = 0.02. Hence, most mass is in hydrogen and helium, while a very small fraction is in heavier elements. In most stellar applications, it is safe to assume that the stars are fully ionised, the only exceptions are stellar atmospheres. So the ...
![David`s Mapping the Heavens[1]](http://s1.studyres.com/store/data/008084229_1-877ead4b57cbb51d927fdcd6d06ce5c8-300x300.png)
5 Understanding stars and star ClUsters
... main sequence. It is believed that stars begin their life at the upper right portion of the graph and then move to their place on the main sequence shortly after they begin to burn their nuclear fuel. Their place on the main sequence is dictated by their mass. The higher the mass the further to the ...
... main sequence. It is believed that stars begin their life at the upper right portion of the graph and then move to their place on the main sequence shortly after they begin to burn their nuclear fuel. Their place on the main sequence is dictated by their mass. The higher the mass the further to the ...
Integrated Science
... Neutron stars are one of the possible ends for a star. They result from massive stars which have mass greater than 4 to 8 times that of our Sun. After these stars have finished burning their nuclear fuel, they undergo a supernova explosion. This explosion blows off the outer layers of a star into ...
... Neutron stars are one of the possible ends for a star. They result from massive stars which have mass greater than 4 to 8 times that of our Sun. After these stars have finished burning their nuclear fuel, they undergo a supernova explosion. This explosion blows off the outer layers of a star into ...
Far Ultraviolet Spectroscopic Explorer
... (*not* 2500 ly, which had been used for 40 years!) Hubble WFPC2 Difference image: 1997 to 2001 ...
... (*not* 2500 ly, which had been used for 40 years!) Hubble WFPC2 Difference image: 1997 to 2001 ...
Stars - cayugascience
... explosion is directed not only outward, but also inward. This force causes the atoms in the star’s core to compress and collapse. When an atom collapses, it forms neutrons, particles that are at the centre of most atoms already. When the star’s core becomes little more than a ball of neutrons only a ...
... explosion is directed not only outward, but also inward. This force causes the atoms in the star’s core to compress and collapse. When an atom collapses, it forms neutrons, particles that are at the centre of most atoms already. When the star’s core becomes little more than a ball of neutrons only a ...
black holes activity
... the time it get to 200,000 km out it is turned into energy and through convection transferred towards the surface C.What is Granulation? -Looking at the surface of the Sun it looks highly ________________ -Each granule is about 1000 km across, has a lifetime of __________________ and depending on it ...
... the time it get to 200,000 km out it is turned into energy and through convection transferred towards the surface C.What is Granulation? -Looking at the surface of the Sun it looks highly ________________ -Each granule is about 1000 km across, has a lifetime of __________________ and depending on it ...
Type II supernova
A Type II supernova (plural: supernovae or supernovas) results from the rapid collapse and violent explosion of a massive star. A star must have at least 8 times, and no more than 40–50 times, the mass of the Sun (M☉) for this type of explosion. It is distinguished from other types of supernovae by the presence of hydrogen in its spectrum. Type II supernovae are mainly observed in the spiral arms of galaxies and in H II regions, but not in elliptical galaxies.Stars generate energy by the nuclear fusion of elements. Unlike the Sun, massive stars possess the mass needed to fuse elements that have an atomic mass greater than hydrogen and helium, albeit at increasingly higher temperatures and pressures, causing increasingly shorter stellar life spans. The degeneracy pressure of electrons and the energy generated by these fusion reactions are sufficient to counter the force of gravity and prevent the star from collapsing, maintaining stellar equilibrium. The star fuses increasingly higher mass elements, starting with hydrogen and then helium, progressing up through the periodic table until a core of iron and nickel is produced. Fusion of iron or nickel produces no net energy output, so no further fusion can take place, leaving the nickel-iron core inert. Due to the lack of energy output allowing outward pressure, equilibrium is broken.When the mass of the inert core exceeds the Chandrasekhar limit of about 1.4 M☉, electron degeneracy alone is no longer sufficient to counter gravity and maintain stellar equilibrium. A cataclysmic implosion takes place within seconds, in which the outer core reaches an inward velocity of up to 23% of the speed of light and the inner core reaches temperatures of up to 100 billion kelvin. Neutrons and neutrinos are formed via reversed beta-decay, releasing about 1046 joules (100 foes) in a ten-second burst. The collapse is halted by neutron degeneracy, causing the implosion to rebound and bounce outward. The energy of this expanding shock wave is sufficient to accelerate the surrounding stellar material to escape velocity, forming a supernova explosion, while the shock wave and extremely high temperature and pressure briefly allow for theproduction of elements heavier than iron. Depending on initial size of the star, the remnants of the core form a neutron star or a black hole. Because of the underlying mechanism, the resulting nova is also described as a core-collapse supernova.There exist several categories of Type II supernova explosions, which are categorized based on the resulting light curve—a graph of luminosity versus time—following the explosion. Type II-L supernovae show a steady (linear) decline of the light curve following the explosion, whereas Type II-P display a period of slower decline (a plateau) in their light curve followed by a normal decay. Type Ib and Ic supernovae are a type of core-collapse supernova for a massive star that has shed its outer envelope of hydrogen and (for Type Ic) helium. As a result, they appear to be lacking in these elements.