Review for Exam 2
... Which 3 factors determine if a planet holds onto an atmosphere? What is the primary reason why Venus is much hoMer than ...
... Which 3 factors determine if a planet holds onto an atmosphere? What is the primary reason why Venus is much hoMer than ...
Stars - staff.harrisonburg.k12.va
... • A ball of matter that is pulled together by gravity, and that gives off energy as a result of NUCLEAR FUSION. – Nuclear fusion- when two atoms bond together to make one heavier atom. The process releases large amounts of energy. ...
... • A ball of matter that is pulled together by gravity, and that gives off energy as a result of NUCLEAR FUSION. – Nuclear fusion- when two atoms bond together to make one heavier atom. The process releases large amounts of energy. ...
Stars
... • A ball of matter that is pulled together by gravity, and that gives off energy as a result of NUCLEAR FUSION. – Nuclear fusion- when two atoms bond together to make one heavier atom. The process releases large amounts of energy. ...
... • A ball of matter that is pulled together by gravity, and that gives off energy as a result of NUCLEAR FUSION. – Nuclear fusion- when two atoms bond together to make one heavier atom. The process releases large amounts of energy. ...
Teacher Guide
... A Cepheid variable star that appears very bright, but has a short period, is relatively close to our solar system. ...
... A Cepheid variable star that appears very bright, but has a short period, is relatively close to our solar system. ...
Page 1 of 4 Name PSCI 1055 Test #4 (Form B) Spring 2008 Buckley
... b. What type of star has the lowest temperature but the highest level of brightness on the H-R diagram? ...
... b. What type of star has the lowest temperature but the highest level of brightness on the H-R diagram? ...
... the interior to the surface is radiative, convection playing a secondary role in certain classes of stars. Condition is too slow a process to play any accountable role. If I(r, e ) is the intensity of radiation, being the energy per unit area per second per unit solid angle d w of the radiation at a ...
Stellar Astronomy Sample Questions for Exam 3
... 1. Briefly describe the nebular model for the formation of the solar system. Include details about the formation of both the central star and the planets around it. 2. Describe some of the evidence we have for how we think solar systems like ours form. Where do they form? What types of objects have ...
... 1. Briefly describe the nebular model for the formation of the solar system. Include details about the formation of both the central star and the planets around it. 2. Describe some of the evidence we have for how we think solar systems like ours form. Where do they form? What types of objects have ...
Sample Midterm - IUPUI Physics
... 17. A particular star has a B-V value of 0.9 at a distance of 12 parsecs. If a similar star were to be found at a distance of 1200 parsecs and you ignore absorption of light be dust then what would the B-V value of that star be? a) 90 b) 9 * 10-3 c) 1188.9 d) 0.9 18. In the core of the sun when two ...
... 17. A particular star has a B-V value of 0.9 at a distance of 12 parsecs. If a similar star were to be found at a distance of 1200 parsecs and you ignore absorption of light be dust then what would the B-V value of that star be? a) 90 b) 9 * 10-3 c) 1188.9 d) 0.9 18. In the core of the sun when two ...
d - Haus der Astronomie
... By averaging, we find the approximate distance to the Andromeda Galaxy: (2,52 ± 0,14) 10 lyly ...
... By averaging, we find the approximate distance to the Andromeda Galaxy: (2,52 ± 0,14) 10 lyly ...
Introduction
... This set of linear equations can be solved (if the determinant is not zero) to get the α∗ values. For example, consider upper MS stars as a homologous sequence. For these stars, the opacity is mostly due to electron scattering (i.e., n = s = 0) and the nuclear reaction is due to CNO cycles (i.e., λ ...
... This set of linear equations can be solved (if the determinant is not zero) to get the α∗ values. For example, consider upper MS stars as a homologous sequence. For these stars, the opacity is mostly due to electron scattering (i.e., n = s = 0) and the nuclear reaction is due to CNO cycles (i.e., λ ...
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.